Revert "Separate type for unaggregated network attestations (#14659 )"

This reverts commit 153d1872ae.
Merge branch 'develop' into peerDAS
2026-01-10 05:47:59 -05:00 · 2025-01-15 21:17:24 +01:00 · 2025-01-15 20:59:22 +01:00 · 2025-01-15 19:50:48 +00:00 · 2025-01-15 20:48:25 +01:00 · 2025-01-15 18:07:00 +00:00
843 changed files with 77032 additions and 46023 deletions
--- a/.bazelrc
+++ b/.bazelrc
@@ -22,6 +22,7 @@ coverage --define=coverage_enabled=1
 build --workspace_status_command=./hack/workspace_status.sh

 build --define blst_disabled=false
+build --compilation_mode=opt
 run --define blst_disabled=false

 build:blst_disabled --define blst_disabled=true
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -33,5 +33,5 @@ Fixes #
 **Acknowledgements**

 - [ ] I have read [CONTRIBUTING.md](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md).
- [ ] I have made an appropriate entry to [CHANGELOG.md](https://github.com/prysmaticlabs/prysm/blob/develop/CHANGELOG.md).
+- [ ] I have included a uniquely named [changelog fragment file](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md#maintaining-changelogmd).
 - [ ] I have added a description to this PR with sufficient context for reviewers to understand this PR.
--- a/.github/workflows/changelog.yml
+++ b/.github/workflows/changelog.yml
@@ -1,33 +1,33 @@
-name: CI
+# This workflow will build a golang project
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-go
+
+name: changelog

 on:
  pull_request:
-    branches:
-      - develop
+    branches: [ "develop" ]

 jobs:
-  changed_files:
-    runs-on: ubuntu-latest 
-    name: Check CHANGELOG.md
+  run-changelog-check:
+    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
-      - name: changelog modified
-        id: changelog-modified
+      - name: Checkout source code
+        uses: actions/checkout@v3
+
+      - name: Download unclog binary
+        uses: dsaltares/fetch-gh-release-asset@aa2ab1243d6e0d5b405b973c89fa4d06a2d0fff7 # 1.1.2
+        with:
+          repo: OffchainLabs/unclog
+          file: "unclog"
+
+      - name: Get new changelog files
+        id: new-changelog-files
        uses: tj-actions/changed-files@v45
        with:
-          files: CHANGELOG.md
+          files: |
+            changelog/**.md

-      - name: List all changed files
+      - name: Run lint command
        env:
-          ALL_CHANGED_FILES: ${{ steps.changelog-modified.outputs.all_changed_files }}
-        run: |
-          if [[ ${ALL_CHANGED_FILES[*]} =~ (^|[[:space:]])"CHANGELOG.md"($|[[:space:]]) ]];
-          then
-            echo "CHANGELOG.md was modified.";
-            exit 0;
-          else
-            echo "CHANGELOG.md was not modified.";
-            echo "Please see CHANGELOG.md and follow the instructions to add your changes to that file."
-            echo "In some rare scenarios, a changelog entry is not required and this CI check can be ignored."
-            exit 1;
-          fi
+          ALL_ADDED_MARKDOWN: ${{ steps.new-changelog-files.outputs.added_files }}
+        run: chmod +x unclog && ./unclog check -fragment-env=ALL_ADDED_MARKDOWN
--- a/.github/workflows/fuzz.yml
+++ b/.github/workflows/fuzz.yml
@@ -16,7 +16,7 @@ jobs:
      - uses: actions/checkout@v3
      - uses: actions/setup-go@v4
        with:
-          go-version: '1.22.3'
+          go-version: '1.22.10'
      - id: list
        uses: shogo82148/actions-go-fuzz/list@v0
        with:
@@ -36,7 +36,7 @@ jobs:
      - uses: actions/checkout@v3
      - uses: actions/setup-go@v4
        with:
-          go-version: '1.22.3'
+          go-version: '1.22.10'
      - uses: shogo82148/actions-go-fuzz/run@v0
        with:
          packages: ${{ matrix.package }}
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -31,7 +31,7 @@ jobs:
      - name: Set up Go 1.22
        uses: actions/setup-go@v4
        with:
-          go-version: '1.22.6'
+          go-version: '1.22.10'
      - name: Run Gosec Security Scanner
        run: | # https://github.com/securego/gosec/issues/469
          export PATH=$PATH:$(go env GOPATH)/bin
@@ -48,13 +48,13 @@ jobs:
      - name: Set up Go 1.22
        uses: actions/setup-go@v4
        with:
-          go-version: '1.22.6'
+          go-version: '1.22.10'
          id: go

      - name: Golangci-lint
        uses: golangci/golangci-lint-action@v5
        with:
-          version: v1.55.2
+          version: v1.56.1
          args: --config=.golangci.yml --out-${NO_FUTURE}format colored-line-number

  build:
@@ -64,7 +64,7 @@ jobs:
      - name: Set up Go 1.x
        uses: actions/setup-go@v4
        with:
-          go-version: '1.22.6'
+          go-version: '1.22.10'
        id: go

      - name: Check out code into the Go module directory
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -6,7 +6,7 @@ run:
    - proto
    - tools/analyzers
  timeout: 10m
-  go: '1.22.6'
+  go: '1.22.10'

 linters:
  enable-all: true
@@ -73,6 +73,7 @@ linters:
    - promlinter
    - protogetter
    - revive
+    - spancheck
    - staticcheck
    - stylecheck
    - tagalign
--- a/.policy.yml
+++ b/.policy.yml
@@ -26,7 +26,6 @@ approval_rules:
      only_changed_files:
        paths:
          - "*pb.go"
-          - "*pb.gw.go"
          - "*.bazel"
    options:
      ignore_commits_by:
@@ -69,7 +68,6 @@ approval_rules:
      changed_files:
        ignore:
          - "*pb.go"
-          - "*pb.gw.go"
          - "*.bazel"
    options:
      ignore_commits_by:
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,7 +4,171 @@ All notable changes to this project will be documented in this file.

 The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

-## [Unreleased](https://github.com/prysmaticlabs/prysm/compare/v5.1.0...HEAD)
+## [v5.2.0](https://github.com/prysmaticlabs/prysm/compare/v5.1.2...v5.2.0)
+
+Updating to this release is highly recommended, especially for users running v5.1.1 or v5.1.2.
+This release is **mandatory** for all validator clients using mev-boost with a gas limit increase.
+Without upgrading to this release, validator clients will default to using local execution blocks
+when the gas limit starts to increase.
+
+This release has several fixes and new features. In this release, we have enabled QUIC protocol by
+default, which uses port 13000 for `--p2p-quic-port`. This may be a [breaking change](https://github.com/prysmaticlabs/prysm/pull/14688#issuecomment-2516713826)
+if you're using port 13000 already. This release has some improvements for raising the gas limit,
+but there are [known issues](https://hackmd.io/@ttsao/prysm-gas-limit) with the proposer settings
+file provided gas limit not being respected for mev-boost outsourced blocks. Signalling an increase
+for the gas limit works perfectly for local block production as of this release. See [pumpthegas.org](https://pumpthegas.org) for more info on raising the gas limit on L1.
+
+Notable features:
+- Prysm can reuse blobs from the EL via engine_getBlobsV1, [potentially saving bandwidth](https://hackmd.io/@ttsao/get-blobs-early-results).
+- QUIC is enabled by default. This is a UDP based networking protocol with default port 13000.
+
+### Added
+
+- Electra EIP6110: Queue deposit [pr](https://github.com/prysmaticlabs/prysm/pull/14430).
+- Add Bellatrix tests for light client functions.
+- Add Discovery Rebooter Feature.
+- Added GetBlockAttestationsV2 endpoint.
+- Light client support: Consensus types for Electra.
+- Added SubmitPoolAttesterSlashingV2 endpoint.
+- Added SubmitAggregateAndProofsRequestV2 endpoint.
+- Updated the `beacon-chain/monitor` package to Electra. [PR](https://github.com/prysmaticlabs/prysm/pull/14562)
+- Added ListAttestationsV2 endpoint.
+- Add ability to rollback node's internal state during processing.
+- Change how unsafe protobuf state is created to prevent unnecessary copies.
+- Added benchmarks for process slots for Capella, Deneb, Electra.
+- Add helper to cast bytes to string without allocating memory.
+- Added GetAggregatedAttestationV2 endpoint.
+- Added SubmitAttestationsV2 endpoint.
+- Validator REST mode Electra block support.
+- Added validator index label to `validator_statuses` metric.
+- Added Validator REST mode use of Attestation V2 endpoints and Electra attestations.
+- PeerDAS: Added proto for `DataColumnIdentifier`, `DataColumnSidecar`, `DataColumnSidecarsByRangeRequest` and `MetadataV2`.
+- Better attestation packing for Electra. [PR](https://github.com/prysmaticlabs/prysm/pull/14534)
+- P2P: Add logs when a peer is (dis)connected. Add the reason of the disconnection when we initiate it.
+- Added a Prometheus error counter metric for HTTP requests to track beacon node requests.
+- Added a Prometheus error counter metric for SSE requests.
+- Save light client updates and bootstraps in DB.
+- Added more comprehensive tests for `BlockToLightClientHeader`. [PR](https://github.com/prysmaticlabs/prysm/pull/14699)
+- Added light client feature flag check to RPC handlers. [PR](https://github.com/prysmaticlabs/prysm/pull/14736)
+- Light client: Add better error handling. [PR](https://github.com/prysmaticlabs/prysm/pull/14749)
+
+### Changed
+
+- Electra EIP6110: Queue deposit requests changes from consensus spec pr #3818
+- reversed the boolean return on `BatchVerifyDepositsSignatures`, from need verification, to all keys successfully verified
+- Fix `engine_exchangeCapabilities` implementation.
+- Updated the default `scrape-interval` in `Client-stats` to 2 minutes to accommodate Beaconcha.in API rate limits.
+- Switch to compounding when consolidating with source==target.
+- Revert block db save when saving state fails.
+- Return false from HasBlock if the block is being synced. 
+- Cleanup forkchoice on failed insertions.
+- Use read only validator for core processing to avoid unnecessary copying.
+- Use ROBlock across block processing pipeline.
+- Added missing Eth-Consensus-Version headers to GetBlockAttestationsV2 and GetAttesterSlashingsV2 endpoints.
+- When instantiating new validators, explicit set `Slashed` to false and move `EffectiveBalance` to match struct definition.
+- Updated pgo profile for beacon chain with holesky data. This improves the profile guided
+  optimizations in the go compiler.
+- Use read only state when computing the active validator list.
+- Simplified `ExitedValidatorIndices`.
+- Simplified `EjectedValidatorIndices`.
+- `engine_newPayloadV4`,`engine_getPayloadV4` are changes due to new execution request serialization decisions, [PR](https://github.com/prysmaticlabs/prysm/pull/14580)
+- Fixed various small things in state-native code.
+- Use ROBlock earlier in block syncing pipeline. 
+- Changed the signature of `ProcessPayload`.
+- Only Build the Protobuf state once during serialization.
+- Capella blocks are execution.
+- Fixed panic when http request to subscribe to event stream fails.
+- Return early for blob reconstructor during capella fork.
+- Updated block endpoint from V1 to V2.
+- Rename instances of "deposit receipts" to "deposit requests".
+- Non-blocking payload attribute event handling in beacon api [pr](https://github.com/prysmaticlabs/prysm/pull/14644).
+- Updated light client protobufs. [PR](https://github.com/prysmaticlabs/prysm/pull/14650)
+- Added `Eth-Consensus-Version` header to `ListAttestationsV2` and `GetAggregateAttestationV2` endpoints.
+- Updated light client consensus types. [PR](https://github.com/prysmaticlabs/prysm/pull/14652)
+- Update earliest exit epoch for upgrade to electra
+- Add missed exit checks to consolidation processing
+- Fixed pending deposits processing on Electra.
+- Modified `ListAttestationsV2`, `GetAttesterSlashingsV2` and `GetAggregateAttestationV2` endpoints to use slot to determine fork version.
+- Improvements to HTTP response handling. [pr](https://github.com/prysmaticlabs/prysm/pull/14673)
+- Updated `Blobs` endpoint to return additional metadata fields.
+- Made QUIC the default method to connect with peers.
+- Check kzg commitments align with blobs and proofs for beacon api end point.
+- Revert "Proposer checks gas limit before accepting builder's bid".
+- Updated quic-go to v0.48.2 .
+
+### Deprecated
+
+- `/eth/v1alpha1/validator/activation/stream` grpc wait for activation stream is deprecated. [pr](https://github.com/prysmaticlabs/prysm/pull/14514)
+- `--interop-genesis-time` and `--interop-num-validators` have been deprecated in the beacon node as the functionality has been removed. These flags have no effect.
+
+### Removed
+
+- Removed finalized validator index cache, no longer needed.
+- Removed validator queue position log on key reload and wait for activation.
+- Removed outdated spectest exclusions for EIP-6110.
+- Removed support for starting a beacon node with a deterministic interop genesis state via interop flags. Alternatively, create a genesis state with prysmctl and use `--genesis-state`. This removes about 9Mb (~11%) of unnecessary code and dependencies from the final production binary.
+- Removed kzg proof check from blob reconstructor.
+
+### Fixed
+
+- Fixed mesh size by appending `gParams.Dhi = gossipSubDhi`
+- Fix skipping partial withdrawals count.
+- wait for the async StreamEvent writer to exit before leaving the http handler, avoiding race condition panics [pr](https://github.com/prysmaticlabs/prysm/pull/14557)
+- Certain deb files were returning a 404 which made building new docker images without an existing
+  cache impossible. This has been fixed with updates to rules_oci and bazel-lib.
+- Fixed an issue where the length check between block body KZG commitments and the existing cache from the database was incompatible.
+- Fix `--backfill-oldest-slot` handling - this flag was totally broken, the code would always backfill to the default slot [pr](https://github.com/prysmaticlabs/prysm/pull/14584)
+- Fix keymanager API should return corrected error format for malformed tokens
+- Fix keymanager API so that get keys returns an empty response instead of a 500 error when using an unsupported keystore.
+- Small log improvement, removing some redundant or duplicate logs
+- EIP7521 - Fixes withdrawal bug by accounting for pending partial withdrawals and deducting already withdrawn amounts from the sweep balance. [PR](https://github.com/prysmaticlabs/prysm/pull/14578)
+- unskip electra merkle spec test
+- Fix panic in validator REST mode when checking status after removing all keys
+- Fix panic on attestation interface since we call data before validation
+- corrects nil check on some interface attestation types
+- temporary solution to handling electra attesation and attester_slashing events. [pr](14655)
+- Diverse log improvements and comment additions.
+- Validate that each committee bitfield in an aggregate contains at least one non-zero bit
+- P2P: Avoid infinite loop when looking for peers in small networks.
+- Fixed another rollback bug due to a context deadline.
+- Fix checkpoint sync bug on holesky. [pr](https://github.com/prysmaticlabs/prysm/pull/14689)
+- Fix proposer boost spec tests being flakey by adjusting start time from 3 to 2s into slot.
+- Fix segmentation fault in E2E when light-client feature flag is enabled. [PR](https://github.com/prysmaticlabs/prysm/pull/14699)
+- Fix `searchForPeers` infinite loop in small networks.
+- Fix slashing pool behavior to enforce MaxAttesterSlashings limit in Electra version.
+
+### Security
+
+## [v5.1.2](https://github.com/prysmaticlabs/prysm/compare/v5.1.1...v5.1.2) - 2024-10-16 
+
+This is a hotfix release with one change. 
+
+Prysm v5.1.1 contains an updated implementation of the beacon api streaming events endpoint. This
+new implementation contains a bug that can cause a panic in certain conditions. The issue is
+difficult to reproduce reliably and we are still trying to determine the root cause, but in the
+meantime we are issuing a patch that recovers from the panic to prevent the node from crashing.
+
+This only impacts the v5.1.1 release beacon api event stream endpoints. This endpoint is used by the
+prysm REST mode validator (a feature which requires the validator to be configured to use the beacon
+api instead of prysm's stock grpc endpoints) or accessory software that connects to the events api,
+like https://github.com/ethpandaops/ethereum-metrics-exporter
+
+### Fixed 
+
+- Recover from panics when writing the event stream [#14545](https://github.com/prysmaticlabs/prysm/pull/14545)
+
+## [v5.1.1](https://github.com/prysmaticlabs/prysm/compare/v5.1.0...v5.1.1) - 2024-10-15
+
+This release has a number of features and improvements. Most notably, the feature flag 
+`--enable-experimental-state` has been flipped to "opt out" via `--disable-experimental-state`. 
+The experimental state management design has shown significant improvements in memory usage at
+runtime. Updates to libp2p's gossipsub have some bandwidith stability improvements with support for
+IDONTWANT control messages. 
+
+The gRPC gateway has been deprecated from Prysm in this release. If you need JSON data, consider the
+standardized beacon-APIs. 
+
+Updating to this release is recommended at your convenience.

 ### Added

@@ -13,10 +177,23 @@ The format is based on Keep a Changelog, and this project adheres to Semantic Ve
 - Light client support: Implement `ComputeFieldRootsForBlockBody`.
 - Light client support: Add light client database changes.
 - Light client support: Implement capella and deneb changes.
- Light client support: Implement `BlockToLightClientHeaderXXX` functions upto Deneb
+- Light client support: Implement `BlockToLightClientHeader` function.
+- Light client support: Consensus types.
+- GetBeaconStateV2: add Electra case.
+- Implement [consensus-specs/3875](https://github.com/ethereum/consensus-specs/pull/3875).
+- Tests to ensure sepolia config matches the official upstream yaml.
+- `engine_newPayloadV4`,`engine_getPayloadV4` used for electra payload communication with execution client.  [pr](https://github.com/prysmaticlabs/prysm/pull/14492)
+- HTTP endpoint for PublishBlobs.
+- GetBlockV2, GetBlindedBlock, ProduceBlockV2, ProduceBlockV3: add Electra case.
+- Add Electra support and tests for light client functions.
+- fastssz version bump (better error messages).
+- SSE implementation that sheds stuck clients. [pr](https://github.com/prysmaticlabs/prysm/pull/14413)
+- Added GetPoolAttesterSlashingsV2 endpoint.
+- Use engine API get-blobs for block subscriber to reduce block import latency and potentially reduce bandwidth.

 ### Changed

+- Electra: Updated interop genesis generator to support Electra.
 - `getLocalPayload` has been refactored to enable work in ePBS branch.
 - `TestNodeServer_GetPeer` and `TestNodeServer_ListPeers` test flakes resolved by iterating the whole peer list to find
  a match rather than taking the first peer in the map.
@@ -37,6 +214,12 @@ The format is based on Keep a Changelog, and this project adheres to Semantic Ve
 - Updated k8s-io/client-go to v0.30.4 and k8s-io/apimachinery to v0.30.4
 - Migrated tracing library from opencensus to opentelemetry for both the beacon node and validator.
 - Refactored light client code to make it more readable and make future PRs easier.
+- Update light client helper functions to reference `dev` branch of CL specs
+- Updated Libp2p Dependencies to allow prysm to use gossipsub v1.2 .
+- Updated Sepolia bootnodes.
+- Make committee aware packing the default by deprecating `--enable-committee-aware-packing`.
+- Moved `ConvertKzgCommitmentToVersionedHash` to the `primitives` package.
+- Updated correlation penalty for EIP-7251. 

 ### Deprecated
 - `--disable-grpc-gateway` flag is deprecated due to grpc gateway removal.
@@ -44,9 +227,10 @@ The format is based on Keep a Changelog, and this project adheres to Semantic Ve

 ### Removed

- removed gRPC Gateway
- Removed unused blobs bundle cache
+- Removed gRPC Gateway.
+- Removed unused blobs bundle cache.
 - Removed consolidation signing domain from params. The Electra design changed such that EL handles consolidation signature verification.
+- Remove engine_getPayloadBodiesBy{Hash|Range}V2

 ### Fixed

@@ -58,12 +242,19 @@ The format is based on Keep a Changelog, and this project adheres to Semantic Ve
 - validator registration log changed to debug, and the frequency of validator registration calls are reduced
 - Core: Fix process effective balance update to safe copy validator for Electra.
 - `== nil` checks before calling `IsNil()` on interfaces to prevent panics.
- Core: Fixed slash processing causing extra hashing
- Core: Fixed extra allocations when processing slashings
+- Core: Fixed slash processing causing extra hashing.
+- Core: Fixed extra allocations when processing slashings.
 - remove unneeded container in blob sidecar ssz response
+- Light client support: create finalized header based on finalizedBlock's version, not attestedBlock.
+- Light client support: fix light client attested header execution fields' wrong version bug.
+- Testing: added custom matcher for better push settings testing.
+- Registered `GetDepositSnapshot` Beacon API endpoint.
+- Fix rolling back of a block due to a context deadline.

 ### Security

+No notable security updates.
+
 ## [v5.1.0](https://github.com/prysmaticlabs/prysm/compare/v5.0.4...v5.1.0) - 2024-08-20

 This release contains 171 new changes and many of these are related to Electra! Along side the Electra changes, there
@@ -202,7 +393,7 @@ Updating to this release is recommended at your earliest convenience, especially
 - use time.NewTimer() to avoid possible memory leaks
 - paranoid underflow protection without error handling
 - Fix CommitteeAssignments to not return every validator
- Fix dependent root retrival genesis case
+- Fix dependent root retrieval genesis case
 - Restrict Dials From Discovery
 - Always close cache warm chan to prevent blocking
 - Keep only the latest value in the health channel
@@ -269,6 +460,7 @@ block profit. If you want to preserve the existing behavior, set --local-block-v
 - Set default LocalBlockValueBoost to 10
 - Add bid value metrics
 - REST VC metrics
+- `startDB`: Add log when checkpoint sync.

 ### Changed

@@ -353,7 +545,7 @@ block profit. If you want to preserve the existing behavior, set --local-block-v
 - handle special case of batch size=1
 - Always Set Inprogress Boolean In Cache
 - Builder APIs: adding headers to post endpoint
- Rename mispelled variable
+- Rename misspelled variable
 - allow blob by root within da period
 - Rewrite Pruning Implementation To Handle EIP 7045
 - Set default fee recipient if tracked val fails
@@ -423,7 +615,7 @@ Known Issues
 - Support beacon_committee_selections
 - /eth/v1/beacon/deposit_snapshot
 - Docker images now have coreutils pre-installed
- da_waited_time_milliseconds tracks total time waiting for data availablity check in ReceiveBlock
+- da_waited_time_milliseconds tracks total time waiting for data availability check in ReceiveBlock
 - blob_written, blob_disk_count, blob_disk_bytes new metrics for tracking blobs on disk
 - Backfill supports blob backfilling
 - Add mainnet deneb fork epoch config
@@ -598,7 +790,7 @@ and Raspberry Pi users.
 - Add Goerli Deneb Fork Epoch
 - Use deneb key for deneb state in saveStatesEfficientInternal
 - Initialize Inactivity Scores Correctly
- Excluse DA wait time for chain processing time
+- Excludes DA wait time for chain processing time
 - Initialize sig cache for verification.Initializer
 - Verify roblobs
 - KZG Commitment inclusion proof verifier
@@ -631,7 +823,7 @@ and Raspberry Pi users.
 - Exit early if blob by root request is empty
 - Request missing blobs while processing pending queue
 - Check blob exists before requesting from peer
- Passing block as arugment for sidecar validation
+- Passing block as argument for sidecar validation

 #### Blob Management

@@ -928,13 +1120,13 @@ _Most of the PRs here involve shifting our http endpoints to using vanilla http
 - Remove no-op cancel func
 - Update Terms of Service
 - fix head slot in log
- DEPRECTATION: Remove exchange transition configuration call
+- DEPRECATION: Remove exchange transition configuration call
 - fix segmentation fork when Capella for epoch is MaxUint64
 - Return Error Gracefully When Removing 4881 Flag
 - Add zero length check on indices during NextSyncCommitteeIndices
 - Replace Empty Slice Literals with Nil Slices
 - Refactor Error String Formatting According to Go Best Practices
- Fix redundant type converstion
+- Fix redundant type conversion
 - docs: fix typo
 - Add Clarification To Sync Committee Cache
 - Fix typos
@@ -956,7 +1148,7 @@ small set of users.

 ### Security

-No security issues in thsi release.
+No security issues in this release.

 ## [v4.1.0](https://github.com/prysmaticlabs/prysm/compare/v4.0.8...v4.1.0) - 2023-08-22

@@ -1472,7 +1664,7 @@ notes [here](https://hackmd.io/TtyFurRJRKuklG3n8lMO9Q). This release is **strong
 Note: The released docker images are using the portable version of the blst cryptography library. The Prysm team will
 release docker images with the non-portable blst library as the default image. In the meantime, you can compile docker
 images with blst non-portable locally with the `--define=blst_modern=true` bazel flag, use the "-modern-" assets
-attached to releases, or set environment varaible USE_PRYSM_MODERN=true when using prysm.sh.
+attached to releases, or set environment variable USE_PRYSM_MODERN=true when using prysm.sh.

 ### Added

@@ -1821,7 +2013,7 @@ There are some known issues with this release.
 - Beacon node can bootstrap from non-genesis state (i.e bellatrix state)
 - Refactor bytesutil, add support for go1.20 slice to array conversions
 - Add Span information for attestation record save request
- Matric addition
+- Metric addition
 - Identify invalid signature within batch verification
 - Support for getting consensus values from beacon config
 - EIP-4881: Spec implementation
@@ -1887,7 +2079,7 @@ See [flashbots/mev-boost#404](https://github.com/flashbots/mev-boost/issues/404)
 - Added more histogram metrics for block arrival latency times block_arrival_latency_milliseconds
 - Priority queue RetrieveByKey now uses read lock instead of write lock
 - Use custom types for certain ethclient requests. Fixes an issue when using prysm on gnosis chain.
- Updted forkchoice endpoint /eth/v1/debug/forkchoice (was /eth/v1/debug/beacon/forkchoice)
+- Updated forkchoice endpoint /eth/v1/debug/forkchoice (was /eth/v1/debug/beacon/forkchoice)
 - Include empty fields in builder json client.
 - Computing committee assignments for slots older than the oldest historical root in the beacon state is now forbidden

@@ -2119,7 +2311,7 @@ There are no security updates in this release.
  removed: `GetBeaconState`, `ProduceBlock`, `ListForkChoiceHeads`, `ListBlocks`, `SubmitValidatorRegistration`, `GetBlock`, `ProposeBlock`
 - API: Forkchoice method `GetForkChoice` has been removed.
 - All previously deprecated feature flags have been
-  removed. `--enable-active-balance-cache`, `--correctly-prune-canonical-atts`, `--correctly-insert-orphaned-atts`, `--enable-next-slot-state-cache`, `--enable-batch-gossip-verification`, `--enable-get-block-optimizations`, `--enable-balance-trie-computation`, `--disable-next-slot-state-cache`, `--attestation-aggregation-strategy`, `--attestation-aggregation-force-opt-maxcover`, `--pyrmont`, `--disable-get-block-optimizations`, `--disable-proposer-atts-selection-using-max-cover`, `--disable-optimized-balance-update`, `--disable-active-balance-cache`, `--disable-balance-trie-computation`, `--disable-batch-gossip-verification`, `--disable-correctly-prune-canonical-atts`, `--disable-correctly-insert-orphaned-atts`, `--enable-native-state`, `--enable-peer-scorer`, `--enable-gossip-batch-aggregation`, `--experimental-disable-boundry-checks`
+  removed. `--enable-active-balance-cache`, `--correctly-prune-canonical-atts`, `--correctly-insert-orphaned-atts`, `--enable-next-slot-state-cache`, `--enable-batch-gossip-verification`, `--enable-get-block-optimizations`, `--enable-balance-trie-computation`, `--disable-next-slot-state-cache`, `--attestation-aggregation-strategy`, `--attestation-aggregation-force-opt-maxcover`, `--pyrmont`, `--disable-get-block-optimizations`, `--disable-proposer-atts-selection-using-max-cover`, `--disable-optimized-balance-update`, `--disable-active-balance-cache`, `--disable-balance-trie-computation`, `--disable-batch-gossip-verification`, `--disable-correctly-prune-canonical-atts`, `--disable-correctly-insert-orphaned-atts`, `--enable-native-state`, `--enable-peer-scorer`, `--enable-gossip-batch-aggregation`, `--experimental-disable-boundary-checks`
 - Validator Web API: Removed unused ImportAccounts and DeleteAccounts rpc options

 ### Fixed
@@ -2335,7 +2527,7 @@ There are two known issues with this release:
 - Bellatrix support. See [kiln testnet instructions](https://hackmd.io/OqIoTiQvS9KOIataIFksBQ?view)
 - Weak subjectivity sync / checkpoint sync. This is an experimental feature and may have unintended side effects for
  certain operators serving historical data. See
-  the [documentation](https://docs.prylabs.network/docs/next/prysm-usage/checkpoint-sync) for more details.
+  the [documentation](https://docs.prylabs.network/docs/prysm-usage/checkpoint-sync) for more details.
 - A faster build of blst for beacon chain on linux amd64. Use the environment variable `USE_PRYSM_MODERN=true` with
  prysm.sh, use the "modern" binary, or bazel build with `--define=blst_modern=true`.
 - Vectorized sha256. This may have performance improvements with use of the new flag `--enable-vectorized-htr`.
@@ -2516,7 +2708,7 @@ notes [here](https://github.com/prysmaticlabs/prysm-web-ui/releases/tag/v1.0.0)
 - Added uint64 overflow protection
 - Sync committee pool returns empty slice instead of nil on cache miss
 - Improved description of datadir flag
- Simplied web password requirements
+- Simplified web password requirements
 - Web JWT tokens no longer expire.
 - Updated keymanager protos
 - Watch and update jwt secret when auth token file updated on disk.
@@ -2527,7 +2719,7 @@ notes [here](https://github.com/prysmaticlabs/prysm-web-ui/releases/tag/v1.0.0)
 - Refactor for weak subjectivity sync implementation
 - Update naming for Atlair previous epoch attester
 - Remove duplicate MerkleizeTrieLeaves method.
- Add explict error for validator flag checks on out of bound positions
+- Add explicit error for validator flag checks on out of bound positions
 - Simplify method to check if the beacon chain client should update the justified epoch value.
 - Rename web UI performance endpoint to "summary"
 - Refactor powchain service to be more functional
@@ -2553,7 +2745,7 @@ notes [here](https://github.com/prysmaticlabs/prysm-web-ui/releases/tag/v1.0.0)
  Upstream go-ethereum is now used with familiar go.mod tooling.
 - Removed duplicate aggergation validation p2p pipelines.
 - Metrics calculation removed extra condition
- Removed superflous errors from peer scoring parameters registration
+- Removed superfluous errors from peer scoring parameters registration

 ### Fixed

@@ -2673,7 +2865,7 @@ on your validators.
 **Beacon chain node**

 | Metric                                           | Description                                                                                           | References |
-|--------------------------------------------------|-------------------------------------------------------------------------------------------------------|------------|
+| ------------------------------------------------ | ----------------------------------------------------------------------------------------------------- | ---------- |
 | `p2p_message_ignored_validation_total`           | Count of messages that were ignored in validation                                                     |            |
 | `beacon_current_active_validators`               | Current total active validators                                                                       |            |
 | `beacon_processed_deposits_total`                | Total number of deposits processed                                                                    |            |
@@ -2724,9 +2916,9 @@ on your validators.
 #### Changed Metrics

 **Beacon chain node**
-| Metric | Old Name | Description | References |
-|-----------------------|----------------------|------------------------------------------------------|------------|
-| `beacon_reorgs_total` | `beacon_reorg_total` | Count the number of times a beacon chain has a reorg | |
+| Metric                | Old Name             | Description                                          | References |
+| --------------------- | -------------------- | ---------------------------------------------------- | ---------- |
+| `beacon_reorgs_total` | `beacon_reorg_total` | Count the number of times a beacon chain has a reorg |            |

 ### Deprecated

--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -125,11 +125,11 @@ Navigate to your fork of the repo on GitHub. On the upper left where the current

 **16. Add an entry to CHANGELOG.md.**

-If your change is user facing, you must include a CHANGELOG.md entry. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.
+All PRs must must include a changelog fragment file in the `changelog` directory. If your change is not user-facing or should not be mentioned in the changelog for some other reason, you may use the `Ignored` changelog section in your fragment's header to satisfy this requirement without altering the final release changelog. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.

 **17. Create a pull request.**

-Navigate your browser to https://github.com/prysmaticlabs/prysm and click on the new pull request button. In the “base” box on the left, leave the default selection “base master”, the branch that you want your changes to be applied to. In the “compare” box on the right, select feature-in-progress-branch, the branch containing the changes you want to apply. You will then be asked to answer a few questions about your pull request. After you complete the questionnaire, the pull request will appear in the list of pull requests at https://github.com/prysmaticlabs/prysm/pulls. Ensure that you have added an entry to CHANGELOG.md if your PR is a user-facing change. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.
+Navigate your browser to https://github.com/prysmaticlabs/prysm and click on the new pull request button. In the “base” box on the left, leave the default selection “base develop”, the branch that you want your changes to be applied to. In the “compare” box on the right, select feature-in-progress-branch, the branch containing the changes you want to apply. You will then be asked to answer a few questions about your pull request. After you complete the questionnaire, the pull request will appear in the list of pull requests at https://github.com/prysmaticlabs/prysm/pulls. Ensure that you have added an entry to CHANGELOG.md if your PR is a user-facing change. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.

 **18. Respond to comments by Core Contributors.**

@@ -177,16 +177,10 @@ $ git push myrepo feature-in-progress-branch -f

 ## Maintaining CHANGELOG.md

-This project follows the changelog guidelines from [keepachangelog.com](https://keepachangelog.com/en/1.1.0/).
-
-All PRs with user facing changes should have an entry in the CHANGELOG.md file and the change should be categorized in the appropriate category within the "Unreleased" section. The categories are:
-
-  `Added` for new features.
-  `Changed` for changes in existing functionality.
-  `Deprecated` for soon-to-be removed features.
-  `Removed` for now removed features.
-  `Fixed` for any bug fixes.
-  `Security` in case of vulnerabilities. Please see the [Security Policy](SECURITY.md) for responsible disclosure before adding a change with this category.
+This project follows the changelog guidelines from [keepachangelog.com](https://keepachangelog.com/en/1.1.0/). In order to minimize conflicts and workflow headaches, we chose to implement a changelog management
+strategy that uses changelog "fragment" files, managed by our changelog management tool called `unclog`. Each PR must include a new changelog fragment file in the `changelog` directory, as specified by unclog's
+[README.md](https://github.com/OffchainLabs/unclog?tab=readme-ov-file#what-is-a-changelog-fragment). As the `unclog` README suggests in the [Best Practices](https://github.com/OffchainLabs/unclog?tab=readme-ov-file#best-practices) section, 
+the standard naming convention for your PR's fragment file, to avoid conflicting with another fragment file, is `changelog/<github user name>_<PR branch name>.md`.

 ### Releasing

--- a/INTEROP.md
+++ b/INTEROP.md
@@ -2,18 +2,21 @@

 This README details how to setup Prysm for interop testing for usage with other Ethereum consensus clients.

+> [!IMPORTANT]  
+> This guide is likely to be outdated. The Prysm team does not have capacity to troubleshoot
+> outdated interop guides or instructions. If you experience issues with this guide, please file an
+> issue for visibility and propose fixes, if possible.
+
 ## Installation & Setup

 1. Install [Bazel](https://docs.bazel.build/versions/master/install.html) **(Recommended)**
 2. `git clone https://github.com/prysmaticlabs/prysm && cd prysm`
-3. `bazel build //...`
+3. `bazel build //cmd/...`

 ## Starting from Genesis

-Prysm supports a few ways to quickly launch a beacon node from basic configurations:
-
- `NumValidators + GenesisTime`: Launches a beacon node by deterministically generating a state from a num-validators flag along with a genesis time **(Recommended)**
- `SSZ Genesis`: Launches a beacon node  from a .ssz file containing a SSZ-encoded, genesis beacon state
+Prysm can be started from a built-in mainnet genesis state, or started with a provided genesis state by
+using the `--genesis-state` flag and providing a path to the genesis.ssz file.

 ## Generating a Genesis State

@@ -21,21 +24,34 @@ To setup the necessary files for these quick starts, Prysm provides a tool to ge
 a deterministically generated set of validator private keys following the official interop YAML format 
 [here](https://github.com/ethereum/eth2.0-pm/blob/master/interop/mocked_start).

-You can use `bazel run //tools/genesis-state-gen` to create a deterministic genesis state for interop.
+You can use `prysmctl` to create a deterministic genesis state for interop.

-### Usage
-
- **--genesis-time** uint: Unix timestamp used as the genesis time in the generated genesis state (defaults to now)
- **--num-validators** int: Number of validators to deterministically include in the generated genesis state
- **--output-ssz** string: Output filename of the SSZ marshaling of the generated genesis state
- **--config-name=interop** string: name of the beacon chain config to use when generating the state. ex mainnet|minimal|interop
-
-The example below creates 64 validator keys, instantiates a genesis state with those 64 validators and with genesis unix timestamp 1567542540,
-and finally writes a ssz encoded output to ~/Desktop/genesis.ssz. This file can be used to kickstart the beacon chain in the next section. When using the `--interop-*` flags, the beacon node will assume the `interop` config should be used, unless a different config is specified on the command line.
+```sh
+# Download (or create) a chain config file.
+curl https://raw.githubusercontent.com/ethereum/consensus-specs/refs/heads/dev/configs/minimal.yaml -o /tmp/minimal.yaml

+# Run prysmctl to generate genesis with a 2 minute genesis delay and 256 validators. 
+bazel run //cmd/prysmctl --config=minimal -- \
+  testnet generate-genesis \
+  --genesis-time-delay=120 \
+  --num-validators=256 \
+  --output-ssz=/tmp/genesis.ssz \
+  --chain-config-file=/tmp/minimal.yaml
 ```
-bazel run //tools/genesis-state-gen -- --config-name interop --output-ssz ~/Desktop/genesis.ssz --num-validators 64 --genesis-time 1567542540
-```
+
+The flags are explained below:
+- `bazel run //cmd/prysmctl` is the bazel command to compile and run prysmctl.
+- `--config=minimal` is a bazel build time configuration flag to compile Prysm with minimal state constants.
+- `--` is an argument divider to tell bazel that everything after this divider should be passed as arguments to prysmctl. Without this divider, it isn't clear to bazel if the arguments are meant to be build time arguments or runtime arguments so the operation complains and fails to build without this divider.
+- `testnet` is the primary command argument for prysmctl.
+- `generate-genesis` is the subcommand to `testnet` in prysmctl.
+- `--genesis-time-delay` uint: The number of seconds in the future to define genesis. Example: a value of 60 will set the genesis time to 1 minute in the future. This should be sufficiently large enough to allow for you to start the beacon node before the genesis time. 
+- `--num-validators` int: Number of validators to deterministically include in the generated genesis state
+- `--output-ssz` string: Output filename of the SSZ marshaling of the generated genesis state
+- `--chain-config-file` string: Filepath to a chain config yaml file.
+
+Note: This guide saves items to the `/tmp/` directory which will not persist if your machine is
+restarted. Consider tweaking the arguments if persistence is needed.

 ## Launching a Beacon Node + Validator Client

@@ -44,45 +60,33 @@ bazel run //tools/genesis-state-gen -- --config-name interop --output-ssz ~/Desk
 Open up two terminal windows, run:

 ```
-bazel run //beacon-chain -- \
--bootstrap-node= \
--deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
--datadir=/tmp/beacon-chain-interop \
--force-clear-db \
--min-sync-peers=0 \
--interop-num-validators 64 \
--interop-eth1data-votes
+bazel run //cmd/beacon-chain --config=minimal -- \
+  --minimal-config \
+  --bootstrap-node= \
+  --deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
+  --datadir=/tmp/beacon-chain-minimal-devnet \
+  --force-clear-db \
+  --min-sync-peers=0 \
+  --genesis-state=/tmp/genesis.ssz \
+  --chain-config-file=/tmp/minimal.yaml
 ```

-This will deterministically generate a beacon genesis state and start
-the system with 64 validators and the genesis time set to the current unix timestamp.
-Wait a bit until your beacon chain starts, and in the other window:
+This will start the system with 256 validators. The flags used can be explained as such:
+
+- `bazel run //cmd/beacon-chain --config=minimal` builds and runs the beacon node in minimal build configuration.
+- `--` is a flag divider to distinguish between bazel flags and flags that should be passed to the application. All flags and arguments after this divider are passed to the beacon chain.
+- `--minimal-config` tells the beacon node to use minimal network configuration. This is different from the compile time state configuration flag `--config=minimal` and both are required.
+- `--bootstrap-node=` disables the default bootstrap nodes. This prevents the client from attempting to peer with mainnet nodes.
+- `--datadir=/tmp/beacon-chain-minimal-devnet` sets the data directory in a temporary location. Change this to your preferred destination.
+- `--force-clear-db` will delete the beaconchain.db file without confirming with the user. This is helpful for iteratively running local devnets without changing the datadir, but less helpful for one off runs where there was no database in the data directory.
+- `--min-sync-peers=0` allows the beacon node to skip initial sync without peers. This is essential because Prysm expects at least a few peers to start the blockchain.
+- `--genesis-state=/tmp/genesis.ssz` defines the path to the generated genesis ssz file. The beacon node will use this as the initial genesis state.
+- `--chain-config-file=/tmp/minimal.yaml` defines the path to the yaml file with the chain configuration.
+
+As soon as the beacon node has started, start the validator in the other terminal window. 

 ```
-bazel run //validator -- --keymanager=interop --keymanageropts='{"keys":64}'
+bazel run //cmd/validator --config=minimal -- --datadir=/tmp/validator --interop-num-validators=256 --minimal-config --suggested-fee-recipient=0x8A04d14125D0FDCDc742F4A05C051De07232EDa4
 ```

-This will launch and kickstart the system with your 64 validators performing their duties accordingly.
-
-### Launching from `genesis.ssz`
-
-Assuming you generated a `genesis.ssz` file with 64 validators, open up two terminal windows, run:
-
-```
- bazel run //beacon-chain -- \
--bootstrap-node= \
--deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
--datadir=/tmp/beacon-chain-interop \
--force-clear-db \
--min-sync-peers=0 \
--interop-genesis-state /path/to/genesis.ssz \
--interop-eth1data-votes
-```
-
-Wait a bit until your beacon chain starts, and in the other window:
-
-```
-bazel run //validator -- --keymanager=interop --keymanageropts='{"keys":64}'
-```
-
-This will launch and kickstart the system with your 64 validators performing their duties accordingly.
+This will launch and kickstart the system with your 256 validators performing their duties accordingly.
--- a/36
+++ b/36
@@ -101,9 +101,9 @@ http_archive(

 http_archive(
    name = "aspect_bazel_lib",
-    sha256 = "f5ea76682b209cc0bd90d0f5a3b26d2f7a6a2885f0c5f615e72913f4805dbb0d",
-    strip_prefix = "bazel-lib-2.5.0",
-    url = "https://github.com/aspect-build/bazel-lib/releases/download/v2.5.0/bazel-lib-v2.5.0.tar.gz",
+    sha256 = "a272d79bb0ac6b6965aa199b1f84333413452e87f043b53eca7f347a23a478e8",
+    strip_prefix = "bazel-lib-2.9.3",
+    url = "https://github.com/bazel-contrib/bazel-lib/releases/download/v2.9.3/bazel-lib-v2.9.3.tar.gz",
 )

 load("@aspect_bazel_lib//lib:repositories.bzl", "aspect_bazel_lib_dependencies", "aspect_bazel_lib_register_toolchains")
@@ -165,7 +165,7 @@ load("@rules_oci//oci:pull.bzl", "oci_pull")
 oci_pull(
    name = "linux_debian11_multiarch_base",  # Debian bullseye
    digest = "sha256:b82f113425c5b5c714151aaacd8039bc141821cdcd3c65202d42bdf9c43ae60b",  # 2023-12-12
-    image = "gcr.io/distroless/cc-debian11",
+    image = "gcr.io/prysmaticlabs/distroless/cc-debian11",
    platforms = [
        "linux/amd64",
        "linux/arm64/v8",
@@ -182,7 +182,7 @@ load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_depe
 go_rules_dependencies()

 go_register_toolchains(
-    go_version = "1.22.4",
+    go_version = "1.22.10",
    nogo = "@//:nogo",
 )

@@ -227,7 +227,7 @@ filegroup(
    url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )

-consensus_spec_version = "v1.5.0-alpha.5"
+consensus_spec_version = "v1.5.0-beta.0"

 bls_test_version = "v0.1.1"

@@ -243,7 +243,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    integrity = "sha256-R9vG5HEL5eGMOAmbkKfJ2jfelNqL5V0xBUPiXOiGM6U=",
+    integrity = "sha256-HdMlTN3wv+hUMCkIRPk+EHcLixY1cSZlvkx3obEp4AM=",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
 )

@@ -259,7 +259,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    integrity = "sha256-AEIiEOlf1XuxoRMCsN+kgJMo4LrS05+biTA1p/7Ro00=",
+    integrity = "sha256-eX/ihmHQ+OvfoGJxSMgy22yAU3SZ3xjsX0FU0EaZrSs=",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
 )

@@ -275,7 +275,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    integrity = "sha256-LH/Xr20yrJRYnbpjRGupMWTIOWt3cpxZJWXgThwVDsk=",
+    integrity = "sha256-k3Onf42vOzIqyddecR6G82sDy3mmDA+R8RN66QjB0GI=",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
 )

@@ -290,7 +290,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    integrity = "sha256-mlytz4MPjKh0DwV7FMiAtnRbJw9B6o78/x66/vmnYc8=",
+    integrity = "sha256-N/d4AwdOSlb70Dr+2l20dfXxNSzJDj/qKA9Rkn8Gb5w=",
    strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
    url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
@@ -342,6 +342,22 @@ filegroup(
    url = "https://github.com/eth-clients/holesky/archive/874c199423ccd180607320c38cbaca05d9a1573a.tar.gz",  # 2024-06-18
 )

+http_archive(
+    name = "sepolia_testnet",
+    build_file_content = """
+filegroup(
+    name = "configs",
+    srcs = [
+        "metadata/config.yaml",
+    ],
+    visibility = ["//visibility:public"],
+)
+""",
+    integrity = "sha256-cY/UgpCcYEhQf7JefD65FI8tn/A+rAvKhcm2/qiVdqY=",
+    strip_prefix = "sepolia-f2c219a93c4491cee3d90c18f2f8e82aed850eab",
+    url = "https://github.com/eth-clients/sepolia/archive/f2c219a93c4491cee3d90c18f2f8e82aed850eab.tar.gz",  # 2024-09-19
+)
+
 http_archive(
    name = "com_google_protobuf",
    sha256 = "9bd87b8280ef720d3240514f884e56a712f2218f0d693b48050c836028940a42",
--- a/api/client/builder/BUILD.bazel
+++ b/api/client/builder/BUILD.bazel
@@ -12,8 +12,10 @@ go_library(
    visibility = ["//visibility:public"],
    deps = [
        "//api:go_default_library",
+        "//api/client:go_default_library",
        "//api/server/structs:go_default_library",
        "//config/fieldparams:go_default_library",
+        "//config/params:go_default_library",
        "//consensus-types:go_default_library",
        "//consensus-types/blocks:go_default_library",
        "//consensus-types/interfaces:go_default_library",
--- a/api/client/builder/client.go
+++ b/api/client/builder/client.go
@@ -14,6 +14,7 @@ import (

 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/api"
+	"github.com/prysmaticlabs/prysm/v5/api/client"
 	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
@@ -176,7 +177,7 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 		err = non200Err(r)
 		return
 	}
-	res, err = io.ReadAll(r.Body)
+	res, err = io.ReadAll(io.LimitReader(r.Body, client.MaxBodySize))
 	if err != nil {
 		err = errors.Wrap(err, "error reading http response body from builder server")
 		return
@@ -281,7 +282,7 @@ func (c *Client) RegisterValidator(ctx context.Context, svr []*ethpb.SignedValid
 	if err != nil {
 		return err
 	}
-	log.WithField("num_registrations", len(svr)).Info("successfully registered validator(s) on builder")
+	log.WithField("registrationCount", len(svr)).Debug("Successfully registered validator(s) on builder")
 	return nil
 }

@@ -358,7 +359,7 @@ func (c *Client) Status(ctx context.Context) error {
 }

 func non200Err(response *http.Response) error {
-	bodyBytes, err := io.ReadAll(response.Body)
+	bodyBytes, err := io.ReadAll(io.LimitReader(response.Body, client.MaxErrBodySize))
 	var errMessage ErrorMessage
 	var body string
 	if err != nil {
--- a/api/client/builder/client_test.go
+++ b/api/client/builder/client_test.go
@@ -16,7 +16,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	types "github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
@@ -124,7 +123,7 @@ func TestClient_RegisterValidator(t *testing.T) {
 func TestClient_GetHeader(t *testing.T) {
 	ctx := context.Background()
 	expectedPath := "/eth/v1/builder/header/23/0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2/0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
-	var slot types.Slot = 23
+	var slot primitives.Slot = 23
 	parentHash := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
 	pubkey := ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a")
 	t.Run("server error", func(t *testing.T) {
@@ -370,7 +369,7 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, 1, len(withdrawals))
 		assert.Equal(t, uint64(1), withdrawals[0].Index)
-		assert.Equal(t, types.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
 		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
 		assert.Equal(t, uint64(1), withdrawals[0].Amount)
 	})
@@ -409,7 +408,7 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, 1, len(withdrawals))
 		assert.Equal(t, uint64(1), withdrawals[0].Index)
-		assert.Equal(t, types.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
 		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
 		assert.Equal(t, uint64(1), withdrawals[0].Amount)
 		require.NotNil(t, blobBundle)
--- a/api/client/builder/types.go
+++ b/api/client/builder/types.go
@@ -9,6 +9,7 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
 	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	types "github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
@@ -1013,7 +1014,7 @@ func (bb *BuilderBidDeneb) ToProto() (*eth.BuilderBidDeneb, error) {
 	if err != nil {
 		return nil, err
 	}
-	if len(bb.BlobKzgCommitments) > fieldparams.MaxBlobsPerBlock {
+	if len(bb.BlobKzgCommitments) > params.BeaconConfig().DeprecatedMaxBlobsPerBlock {
 		return nil, fmt.Errorf("too many blob commitments: %d", len(bb.BlobKzgCommitments))
 	}
 	kzgCommitments := make([][]byte, len(bb.BlobKzgCommitments))
--- a/api/client/client.go
+++ b/api/client/client.go
@@ -10,11 +10,18 @@ import (
 	"github.com/pkg/errors"
 )

+const (
+	MaxBodySize      int64 = 1 << 23 // 8MB default, WithMaxBodySize can override
+	MaxBodySizeState int64 = 1 << 29 // 512MB
+	MaxErrBodySize   int64 = 1 << 17 // 128KB
+)
+
 // Client is a wrapper object around the HTTP client.
 type Client struct {
-	hc      *http.Client
-	baseURL *url.URL
-	token   string
+	hc          *http.Client
+	baseURL     *url.URL
+	token       string
+	maxBodySize int64
 }

 // NewClient constructs a new client with the provided options (ex WithTimeout).
@@ -26,8 +33,9 @@ func NewClient(host string, opts ...ClientOpt) (*Client, error) {
 		return nil, err
 	}
 	c := &Client{
-		hc:      &http.Client{},
-		baseURL: u,
+		hc:          &http.Client{},
+		baseURL:     u,
+		maxBodySize: MaxBodySize,
 	}
 	for _, o := range opts {
 		o(c)
@@ -72,7 +80,7 @@ func (c *Client) NodeURL() string {
 // Get is a generic, opinionated GET function to reduce boilerplate amongst the getters in this package.
 func (c *Client) Get(ctx context.Context, path string, opts ...ReqOption) ([]byte, error) {
 	u := c.baseURL.ResolveReference(&url.URL{Path: path})
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), http.NoBody)
 	if err != nil {
 		return nil, err
 	}
@@ -89,7 +97,7 @@ func (c *Client) Get(ctx context.Context, path string, opts ...ReqOption) ([]byt
 	if r.StatusCode != http.StatusOK {
 		return nil, Non200Err(r)
 	}
-	b, err := io.ReadAll(r.Body)
+	b, err := io.ReadAll(io.LimitReader(r.Body, c.maxBodySize))
 	if err != nil {
 		return nil, errors.Wrap(err, "error reading http response body")
 	}
--- a/api/client/errors.go
+++ b/api/client/errors.go
@@ -25,16 +25,16 @@ var ErrInvalidNodeVersion = errors.New("invalid node version response")
 var ErrConnectionIssue = errors.New("could not connect")

 // Non200Err is a function that parses an HTTP response to handle responses that are not 200 with a formatted error.
-func Non200Err(response *http.Response) error {
-	bodyBytes, err := io.ReadAll(response.Body)
+func Non200Err(r *http.Response) error {
+	b, err := io.ReadAll(io.LimitReader(r.Body, MaxErrBodySize))
 	var body string
 	if err != nil {
 		body = "(Unable to read response body.)"
 	} else {
-		body = "response body:\n" + string(bodyBytes)
+		body = "response body:\n" + string(b)
 	}
-	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
-	switch response.StatusCode {
+	msg := fmt.Sprintf("code=%d, url=%s, body=%s", r.StatusCode, r.Request.URL, body)
+	switch r.StatusCode {
 	case http.StatusNotFound:
 		return errors.Wrap(ErrNotFound, msg)
 	default:
--- a/api/client/event/event_stream.go
+++ b/api/client/event/event_stream.go
@@ -93,6 +93,7 @@ func (h *EventStream) Subscribe(eventsChannel chan<- *Event) {
 			EventType: EventConnectionError,
 			Data:      []byte(errors.Wrap(err, client.ErrConnectionIssue.Error()).Error()),
 		}
+		return
 	}

 	defer func() {
--- a/api/client/event/event_stream_test.go
+++ b/api/client/event/event_stream_test.go
@@ -40,7 +40,7 @@ func TestNewEventStream(t *testing.T) {

 func TestEventStream(t *testing.T) {
 	mux := http.NewServeMux()
-	mux.HandleFunc("/eth/v1/events", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("/eth/v1/events", func(w http.ResponseWriter, _ *http.Request) {
 		flusher, ok := w.(http.Flusher)
 		require.Equal(t, true, ok)
 		for i := 1; i <= 3; i++ {
@@ -79,3 +79,23 @@ func TestEventStream(t *testing.T) {
 		}
 	}
 }
+
+func TestEventStreamRequestError(t *testing.T) {
+	topics := []string{"head"}
+	eventsChannel := make(chan *Event, 1)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// use valid url that will result in failed request with nil body
+	stream, err := NewEventStream(ctx, http.DefaultClient, "http://badhost:1234", topics)
+	require.NoError(t, err)
+
+	// error will happen when request is made, should be received over events channel
+	go stream.Subscribe(eventsChannel)
+
+	event := <-eventsChannel
+	if event.EventType != EventConnectionError {
+		t.Errorf("Expected event type %q, got %q", EventConnectionError, event.EventType)
+	}
+
+}
--- a/api/client/options.go
+++ b/api/client/options.go
@@ -46,3 +46,10 @@ func WithAuthenticationToken(token string) ClientOpt {
 		c.token = token
 	}
 }
+
+// WithMaxBodySize overrides the default max body size of 8MB.
+func WithMaxBodySize(size int64) ClientOpt {
+	return func(c *Client) {
+		c.maxBodySize = size
+	}
+}
--- a/api/headers.go
+++ b/api/headers.go
@@ -1,5 +1,7 @@
 package api

+import "net/http"
+
 const (
 	VersionHeader                 = "Eth-Consensus-Version"
 	ExecutionPayloadBlindedHeader = "Eth-Execution-Payload-Blinded"
@@ -10,3 +12,9 @@ const (
 	EventStreamMediaType          = "text/event-stream"
 	KeepAlive                     = "keep-alive"
 )
+
+// SetSSEHeaders sets the headers needed for a server-sent event response.
+func SetSSEHeaders(w http.ResponseWriter) {
+	w.Header().Set("Content-Type", EventStreamMediaType)
+	w.Header().Set("Connection", KeepAlive)
+}
--- a/api/server/structs/BUILD.bazel
+++ b/api/server/structs/BUILD.bazel
@@ -5,6 +5,7 @@ go_library(
    srcs = [
        "block.go",
        "conversions.go",
+        "conversions_blob.go",
        "conversions_block.go",
        "conversions_lightclient.go",
        "conversions_state.go",
@@ -35,9 +36,8 @@ go_library(
        "//math:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/eth/v1:go_default_library",
-        "//proto/eth/v2:go_default_library",
-        "//proto/migration:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
+        "//runtime/version:go_default_library",
        "@com_github_ethereum_go_ethereum//common:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
--- a/api/server/structs/block.go
+++ b/api/server/structs/block.go
@@ -14,6 +14,10 @@ type SignedMessageJsoner interface {
 	SigString() string
 }

+// ----------------------------------------------------------------------------
+// Phase 0
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlock struct {
 	Message   *BeaconBlock `json:"message"`
 	Signature string       `json:"signature"`
@@ -48,6 +52,29 @@ type BeaconBlockBody struct {
 	VoluntaryExits    []*SignedVoluntaryExit `json:"voluntary_exits"`
 }

+type SignedBeaconBlockHeaderContainer struct {
+	Header    *SignedBeaconBlockHeader `json:"header"`
+	Root      string                   `json:"root"`
+	Canonical bool                     `json:"canonical"`
+}
+
+type SignedBeaconBlockHeader struct {
+	Message   *BeaconBlockHeader `json:"message"`
+	Signature string             `json:"signature"`
+}
+
+type BeaconBlockHeader struct {
+	Slot          string `json:"slot"`
+	ProposerIndex string `json:"proposer_index"`
+	ParentRoot    string `json:"parent_root"`
+	StateRoot     string `json:"state_root"`
+	BodyRoot      string `json:"body_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Altair
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockAltair struct {
 	Message   *BeaconBlockAltair `json:"message"`
 	Signature string             `json:"signature"`
@@ -83,6 +110,10 @@ type BeaconBlockBodyAltair struct {
 	SyncAggregate     *SyncAggregate         `json:"sync_aggregate"`
 }

+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockBellatrix struct {
 	Message   *BeaconBlockBellatrix `json:"message"`
 	Signature string                `json:"signature"`
@@ -155,6 +186,44 @@ type BlindedBeaconBlockBodyBellatrix struct {
 	ExecutionPayloadHeader *ExecutionPayloadHeader `json:"execution_payload_header"`
 }

+type ExecutionPayload struct {
+	ParentHash    string   `json:"parent_hash"`
+	FeeRecipient  string   `json:"fee_recipient"`
+	StateRoot     string   `json:"state_root"`
+	ReceiptsRoot  string   `json:"receipts_root"`
+	LogsBloom     string   `json:"logs_bloom"`
+	PrevRandao    string   `json:"prev_randao"`
+	BlockNumber   string   `json:"block_number"`
+	GasLimit      string   `json:"gas_limit"`
+	GasUsed       string   `json:"gas_used"`
+	Timestamp     string   `json:"timestamp"`
+	ExtraData     string   `json:"extra_data"`
+	BaseFeePerGas string   `json:"base_fee_per_gas"`
+	BlockHash     string   `json:"block_hash"`
+	Transactions  []string `json:"transactions"`
+}
+
+type ExecutionPayloadHeader struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockCapella struct {
 	Message   *BeaconBlockCapella `json:"message"`
 	Signature string              `json:"signature"`
@@ -229,6 +298,46 @@ type BlindedBeaconBlockBodyCapella struct {
 	BLSToExecutionChanges  []*SignedBLSToExecutionChange  `json:"bls_to_execution_changes"`
 }

+type ExecutionPayloadCapella struct {
+	ParentHash    string        `json:"parent_hash"`
+	FeeRecipient  string        `json:"fee_recipient"`
+	StateRoot     string        `json:"state_root"`
+	ReceiptsRoot  string        `json:"receipts_root"`
+	LogsBloom     string        `json:"logs_bloom"`
+	PrevRandao    string        `json:"prev_randao"`
+	BlockNumber   string        `json:"block_number"`
+	GasLimit      string        `json:"gas_limit"`
+	GasUsed       string        `json:"gas_used"`
+	Timestamp     string        `json:"timestamp"`
+	ExtraData     string        `json:"extra_data"`
+	BaseFeePerGas string        `json:"base_fee_per_gas"`
+	BlockHash     string        `json:"block_hash"`
+	Transactions  []string      `json:"transactions"`
+	Withdrawals   []*Withdrawal `json:"withdrawals"`
+}
+
+type ExecutionPayloadHeaderCapella struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+	WithdrawalsRoot  string `json:"withdrawals_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockContentsDeneb struct {
 	SignedBlock *SignedBeaconBlockDeneb `json:"signed_block"`
 	KzgProofs   []string                `json:"kzg_proofs"`
@@ -317,6 +426,50 @@ type BlindedBeaconBlockBodyDeneb struct {
 	BlobKzgCommitments     []string                      `json:"blob_kzg_commitments"`
 }

+type ExecutionPayloadDeneb struct {
+	ParentHash    string        `json:"parent_hash"`
+	FeeRecipient  string        `json:"fee_recipient"`
+	StateRoot     string        `json:"state_root"`
+	ReceiptsRoot  string        `json:"receipts_root"`
+	LogsBloom     string        `json:"logs_bloom"`
+	PrevRandao    string        `json:"prev_randao"`
+	BlockNumber   string        `json:"block_number"`
+	GasLimit      string        `json:"gas_limit"`
+	GasUsed       string        `json:"gas_used"`
+	Timestamp     string        `json:"timestamp"`
+	ExtraData     string        `json:"extra_data"`
+	BaseFeePerGas string        `json:"base_fee_per_gas"`
+	BlockHash     string        `json:"block_hash"`
+	Transactions  []string      `json:"transactions"`
+	Withdrawals   []*Withdrawal `json:"withdrawals"`
+	BlobGasUsed   string        `json:"blob_gas_used"`
+	ExcessBlobGas string        `json:"excess_blob_gas"`
+}
+
+type ExecutionPayloadHeaderDeneb struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+	WithdrawalsRoot  string `json:"withdrawals_root"`
+	BlobGasUsed      string `json:"blob_gas_used"`
+	ExcessBlobGas    string `json:"excess_blob_gas"`
+}
+
+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockContentsElectra struct {
 	SignedBlock *SignedBeaconBlockElectra `json:"signed_block"`
 	KzgProofs   []string                  `json:"kzg_proofs"`
@@ -362,9 +515,10 @@ type BeaconBlockBodyElectra struct {
 	Deposits              []*Deposit                    `json:"deposits"`
 	VoluntaryExits        []*SignedVoluntaryExit        `json:"voluntary_exits"`
 	SyncAggregate         *SyncAggregate                `json:"sync_aggregate"`
-	ExecutionPayload      *ExecutionPayloadElectra      `json:"execution_payload"`
+	ExecutionPayload      *ExecutionPayloadDeneb        `json:"execution_payload"`
 	BLSToExecutionChanges []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
 	BlobKzgCommitments    []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests     *ExecutionRequests            `json:"execution_requests"`
 }

 type BlindedBeaconBlockElectra struct {
@@ -391,191 +545,119 @@ func (s *SignedBlindedBeaconBlockElectra) SigString() string {
 }

 type BlindedBeaconBlockBodyElectra struct {
-	RandaoReveal           string                         `json:"randao_reveal"`
-	Eth1Data               *Eth1Data                      `json:"eth1_data"`
-	Graffiti               string                         `json:"graffiti"`
-	ProposerSlashings      []*ProposerSlashing            `json:"proposer_slashings"`
-	AttesterSlashings      []*AttesterSlashingElectra     `json:"attester_slashings"`
-	Attestations           []*AttestationElectra          `json:"attestations"`
-	Deposits               []*Deposit                     `json:"deposits"`
-	VoluntaryExits         []*SignedVoluntaryExit         `json:"voluntary_exits"`
-	SyncAggregate          *SyncAggregate                 `json:"sync_aggregate"`
-	ExecutionPayloadHeader *ExecutionPayloadHeaderElectra `json:"execution_payload_header"`
-	BLSToExecutionChanges  []*SignedBLSToExecutionChange  `json:"bls_to_execution_changes"`
-	BlobKzgCommitments     []string                       `json:"blob_kzg_commitments"`
+	RandaoReveal           string                        `json:"randao_reveal"`
+	Eth1Data               *Eth1Data                     `json:"eth1_data"`
+	Graffiti               string                        `json:"graffiti"`
+	ProposerSlashings      []*ProposerSlashing           `json:"proposer_slashings"`
+	AttesterSlashings      []*AttesterSlashingElectra    `json:"attester_slashings"`
+	Attestations           []*AttestationElectra         `json:"attestations"`
+	Deposits               []*Deposit                    `json:"deposits"`
+	VoluntaryExits         []*SignedVoluntaryExit        `json:"voluntary_exits"`
+	SyncAggregate          *SyncAggregate                `json:"sync_aggregate"`
+	ExecutionPayloadHeader *ExecutionPayloadHeaderDeneb  `json:"execution_payload_header"`
+	BLSToExecutionChanges  []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
+	BlobKzgCommitments     []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests      *ExecutionRequests            `json:"execution_requests"`
 }

-type SignedBeaconBlockHeaderContainer struct {
-	Header    *SignedBeaconBlockHeader `json:"header"`
-	Root      string                   `json:"root"`
-	Canonical bool                     `json:"canonical"`
+type (
+	ExecutionRequests struct {
+		Deposits       []*DepositRequest       `json:"deposits"`
+		Withdrawals    []*WithdrawalRequest    `json:"withdrawals"`
+		Consolidations []*ConsolidationRequest `json:"consolidations"`
+	}
+)
+
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------
+
+type SignedBeaconBlockContentsFulu struct {
+	SignedBlock *SignedBeaconBlockFulu `json:"signed_block"`
+	KzgProofs   []string               `json:"kzg_proofs"`
+	Blobs       []string               `json:"blobs"`
 }

-type SignedBeaconBlockHeader struct {
-	Message   *BeaconBlockHeader `json:"message"`
-	Signature string             `json:"signature"`
+type BeaconBlockContentsFulu struct {
+	Block     *BeaconBlockFulu `json:"block"`
+	KzgProofs []string         `json:"kzg_proofs"`
+	Blobs     []string         `json:"blobs"`
 }

-type BeaconBlockHeader struct {
-	Slot          string `json:"slot"`
-	ProposerIndex string `json:"proposer_index"`
-	ParentRoot    string `json:"parent_root"`
-	StateRoot     string `json:"state_root"`
-	BodyRoot      string `json:"body_root"`
+type SignedBeaconBlockFulu struct {
+	Message   *BeaconBlockFulu `json:"message"`
+	Signature string           `json:"signature"`
 }

-type ExecutionPayload struct {
-	ParentHash    string   `json:"parent_hash"`
-	FeeRecipient  string   `json:"fee_recipient"`
-	StateRoot     string   `json:"state_root"`
-	ReceiptsRoot  string   `json:"receipts_root"`
-	LogsBloom     string   `json:"logs_bloom"`
-	PrevRandao    string   `json:"prev_randao"`
-	BlockNumber   string   `json:"block_number"`
-	GasLimit      string   `json:"gas_limit"`
-	GasUsed       string   `json:"gas_used"`
-	Timestamp     string   `json:"timestamp"`
-	ExtraData     string   `json:"extra_data"`
-	BaseFeePerGas string   `json:"base_fee_per_gas"`
-	BlockHash     string   `json:"block_hash"`
-	Transactions  []string `json:"transactions"`
+var _ SignedMessageJsoner = &SignedBeaconBlockFulu{}
+
+func (s *SignedBeaconBlockFulu) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
 }

-type ExecutionPayloadHeader struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
+func (s *SignedBeaconBlockFulu) SigString() string {
+	return s.Signature
 }

-type ExecutionPayloadCapella struct {
-	ParentHash    string        `json:"parent_hash"`
-	FeeRecipient  string        `json:"fee_recipient"`
-	StateRoot     string        `json:"state_root"`
-	ReceiptsRoot  string        `json:"receipts_root"`
-	LogsBloom     string        `json:"logs_bloom"`
-	PrevRandao    string        `json:"prev_randao"`
-	BlockNumber   string        `json:"block_number"`
-	GasLimit      string        `json:"gas_limit"`
-	GasUsed       string        `json:"gas_used"`
-	Timestamp     string        `json:"timestamp"`
-	ExtraData     string        `json:"extra_data"`
-	BaseFeePerGas string        `json:"base_fee_per_gas"`
-	BlockHash     string        `json:"block_hash"`
-	Transactions  []string      `json:"transactions"`
-	Withdrawals   []*Withdrawal `json:"withdrawals"`
+type BeaconBlockFulu struct {
+	Slot          string               `json:"slot"`
+	ProposerIndex string               `json:"proposer_index"`
+	ParentRoot    string               `json:"parent_root"`
+	StateRoot     string               `json:"state_root"`
+	Body          *BeaconBlockBodyFulu `json:"body"`
 }

-type ExecutionPayloadHeaderCapella struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
-	WithdrawalsRoot  string `json:"withdrawals_root"`
+type BeaconBlockBodyFulu struct {
+	RandaoReveal          string                        `json:"randao_reveal"`
+	Eth1Data              *Eth1Data                     `json:"eth1_data"`
+	Graffiti              string                        `json:"graffiti"`
+	ProposerSlashings     []*ProposerSlashing           `json:"proposer_slashings"`
+	AttesterSlashings     []*AttesterSlashingElectra    `json:"attester_slashings"`
+	Attestations          []*AttestationElectra         `json:"attestations"`
+	Deposits              []*Deposit                    `json:"deposits"`
+	VoluntaryExits        []*SignedVoluntaryExit        `json:"voluntary_exits"`
+	SyncAggregate         *SyncAggregate                `json:"sync_aggregate"`
+	ExecutionPayload      *ExecutionPayloadDeneb        `json:"execution_payload"`
+	BLSToExecutionChanges []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
+	BlobKzgCommitments    []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests     *ExecutionRequests            `json:"execution_requests"`
 }

-type ExecutionPayloadDeneb struct {
-	ParentHash    string        `json:"parent_hash"`
-	FeeRecipient  string        `json:"fee_recipient"`
-	StateRoot     string        `json:"state_root"`
-	ReceiptsRoot  string        `json:"receipts_root"`
-	LogsBloom     string        `json:"logs_bloom"`
-	PrevRandao    string        `json:"prev_randao"`
-	BlockNumber   string        `json:"block_number"`
-	GasLimit      string        `json:"gas_limit"`
-	GasUsed       string        `json:"gas_used"`
-	Timestamp     string        `json:"timestamp"`
-	ExtraData     string        `json:"extra_data"`
-	BaseFeePerGas string        `json:"base_fee_per_gas"`
-	BlockHash     string        `json:"block_hash"`
-	Transactions  []string      `json:"transactions"`
-	Withdrawals   []*Withdrawal `json:"withdrawals"`
-	BlobGasUsed   string        `json:"blob_gas_used"`
-	ExcessBlobGas string        `json:"excess_blob_gas"`
+type BlindedBeaconBlockFulu struct {
+	Slot          string                      `json:"slot"`
+	ProposerIndex string                      `json:"proposer_index"`
+	ParentRoot    string                      `json:"parent_root"`
+	StateRoot     string                      `json:"state_root"`
+	Body          *BlindedBeaconBlockBodyFulu `json:"body"`
 }

-type ExecutionPayloadHeaderDeneb struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
-	WithdrawalsRoot  string `json:"withdrawals_root"`
-	BlobGasUsed      string `json:"blob_gas_used"`
-	ExcessBlobGas    string `json:"excess_blob_gas"`
+type SignedBlindedBeaconBlockFulu struct {
+	Message   *BlindedBeaconBlockFulu `json:"message"`
+	Signature string                  `json:"signature"`
 }

-type ExecutionPayloadElectra struct {
-	ParentHash            string                  `json:"parent_hash"`
-	FeeRecipient          string                  `json:"fee_recipient"`
-	StateRoot             string                  `json:"state_root"`
-	ReceiptsRoot          string                  `json:"receipts_root"`
-	LogsBloom             string                  `json:"logs_bloom"`
-	PrevRandao            string                  `json:"prev_randao"`
-	BlockNumber           string                  `json:"block_number"`
-	GasLimit              string                  `json:"gas_limit"`
-	GasUsed               string                  `json:"gas_used"`
-	Timestamp             string                  `json:"timestamp"`
-	ExtraData             string                  `json:"extra_data"`
-	BaseFeePerGas         string                  `json:"base_fee_per_gas"`
-	BlockHash             string                  `json:"block_hash"`
-	Transactions          []string                `json:"transactions"`
-	Withdrawals           []*Withdrawal           `json:"withdrawals"`
-	BlobGasUsed           string                  `json:"blob_gas_used"`
-	ExcessBlobGas         string                  `json:"excess_blob_gas"`
-	DepositRequests       []*DepositRequest       `json:"deposit_requests"`
-	WithdrawalRequests    []*WithdrawalRequest    `json:"withdrawal_requests"`
-	ConsolidationRequests []*ConsolidationRequest `json:"consolidation_requests"`
+var _ SignedMessageJsoner = &SignedBlindedBeaconBlockFulu{}
+
+func (s *SignedBlindedBeaconBlockFulu) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
 }

-type ExecutionPayloadHeaderElectra struct {
-	ParentHash                string `json:"parent_hash"`
-	FeeRecipient              string `json:"fee_recipient"`
-	StateRoot                 string `json:"state_root"`
-	ReceiptsRoot              string `json:"receipts_root"`
-	LogsBloom                 string `json:"logs_bloom"`
-	PrevRandao                string `json:"prev_randao"`
-	BlockNumber               string `json:"block_number"`
-	GasLimit                  string `json:"gas_limit"`
-	GasUsed                   string `json:"gas_used"`
-	Timestamp                 string `json:"timestamp"`
-	ExtraData                 string `json:"extra_data"`
-	BaseFeePerGas             string `json:"base_fee_per_gas"`
-	BlockHash                 string `json:"block_hash"`
-	TransactionsRoot          string `json:"transactions_root"`
-	WithdrawalsRoot           string `json:"withdrawals_root"`
-	BlobGasUsed               string `json:"blob_gas_used"`
-	ExcessBlobGas             string `json:"excess_blob_gas"`
-	DepositRequestsRoot       string `json:"deposit_requests_root"`
-	WithdrawalRequestsRoot    string `json:"withdrawal_requests_root"`
-	ConsolidationRequestsRoot string `json:"consolidation_requests_root"`
+func (s *SignedBlindedBeaconBlockFulu) SigString() string {
+	return s.Signature
+}
+
+type BlindedBeaconBlockBodyFulu struct {
+	RandaoReveal           string                        `json:"randao_reveal"`
+	Eth1Data               *Eth1Data                     `json:"eth1_data"`
+	Graffiti               string                        `json:"graffiti"`
+	ProposerSlashings      []*ProposerSlashing           `json:"proposer_slashings"`
+	AttesterSlashings      []*AttesterSlashingElectra    `json:"attester_slashings"`
+	Attestations           []*AttestationElectra         `json:"attestations"`
+	Deposits               []*Deposit                    `json:"deposits"`
+	VoluntaryExits         []*SignedVoluntaryExit        `json:"voluntary_exits"`
+	SyncAggregate          *SyncAggregate                `json:"sync_aggregate"`
+	ExecutionPayloadHeader *ExecutionPayloadHeaderDeneb  `json:"execution_payload_header"`
+	BLSToExecutionChanges  []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
+	BlobKzgCommitments     []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests      *ExecutionRequests            `json:"execution_requests"`
 }
--- a/api/server/structs/conversions.go
+++ b/api/server/structs/conversions.go
@@ -15,6 +15,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/math"
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
+	ethv1 "github.com/prysmaticlabs/prysm/v5/proto/eth/v1"
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 )

@@ -1475,12 +1476,15 @@ func DepositSnapshotFromConsensus(ds *eth.DepositSnapshot) *DepositSnapshot {
 	}
 }

-func PendingBalanceDepositsFromConsensus(ds []*eth.PendingBalanceDeposit) []*PendingBalanceDeposit {
-	deposits := make([]*PendingBalanceDeposit, len(ds))
+func PendingDepositsFromConsensus(ds []*eth.PendingDeposit) []*PendingDeposit {
+	deposits := make([]*PendingDeposit, len(ds))
 	for i, d := range ds {
-		deposits[i] = &PendingBalanceDeposit{
-			Index:  fmt.Sprintf("%d", d.Index),
-			Amount: fmt.Sprintf("%d", d.Amount),
+		deposits[i] = &PendingDeposit{
+			Pubkey:                hexutil.Encode(d.PublicKey),
+			WithdrawalCredentials: hexutil.Encode(d.WithdrawalCredentials),
+			Amount:                fmt.Sprintf("%d", d.Amount),
+			Signature:             hexutil.Encode(d.Signature),
+			Slot:                  fmt.Sprintf("%d", d.Slot),
 		}
 	}
 	return deposits
@@ -1508,3 +1512,44 @@ func PendingConsolidationsFromConsensus(cs []*eth.PendingConsolidation) []*Pendi
 	}
 	return consolidations
 }
+
+func HeadEventFromV1(event *ethv1.EventHead) *HeadEvent {
+	return &HeadEvent{
+		Slot:                      fmt.Sprintf("%d", event.Slot),
+		Block:                     hexutil.Encode(event.Block),
+		State:                     hexutil.Encode(event.State),
+		EpochTransition:           event.EpochTransition,
+		ExecutionOptimistic:       event.ExecutionOptimistic,
+		PreviousDutyDependentRoot: hexutil.Encode(event.PreviousDutyDependentRoot),
+		CurrentDutyDependentRoot:  hexutil.Encode(event.CurrentDutyDependentRoot),
+	}
+}
+
+func FinalizedCheckpointEventFromV1(event *ethv1.EventFinalizedCheckpoint) *FinalizedCheckpointEvent {
+	return &FinalizedCheckpointEvent{
+		Block:               hexutil.Encode(event.Block),
+		State:               hexutil.Encode(event.State),
+		Epoch:               fmt.Sprintf("%d", event.Epoch),
+		ExecutionOptimistic: event.ExecutionOptimistic,
+	}
+}
+
+func EventChainReorgFromV1(event *ethv1.EventChainReorg) *ChainReorgEvent {
+	return &ChainReorgEvent{
+		Slot:                fmt.Sprintf("%d", event.Slot),
+		Depth:               fmt.Sprintf("%d", event.Depth),
+		OldHeadBlock:        hexutil.Encode(event.OldHeadBlock),
+		NewHeadBlock:        hexutil.Encode(event.NewHeadBlock),
+		OldHeadState:        hexutil.Encode(event.OldHeadState),
+		NewHeadState:        hexutil.Encode(event.NewHeadState),
+		Epoch:               fmt.Sprintf("%d", event.Epoch),
+		ExecutionOptimistic: event.ExecutionOptimistic,
+	}
+}
+
+func SyncAggregateFromConsensus(sa *eth.SyncAggregate) *SyncAggregate {
+	return &SyncAggregate{
+		SyncCommitteeBits:      hexutil.Encode(sa.SyncCommitteeBits),
+		SyncCommitteeSignature: hexutil.Encode(sa.SyncCommitteeSignature),
+	}
+}
--- a/api/server/structs/conversions_blob.go
+++ b/api/server/structs/conversions_blob.go
@@ -0,0 +1,61 @@
+package structs
+
+import (
+	"strconv"
+
+	"github.com/prysmaticlabs/prysm/v5/api/server"
+	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
+	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+)
+
+func (sc *Sidecar) ToConsensus() (*eth.BlobSidecar, error) {
+	if sc == nil {
+		return nil, errNilValue
+	}
+
+	index, err := strconv.ParseUint(sc.Index, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Index")
+	}
+
+	blob, err := bytesutil.DecodeHexWithLength(sc.Blob, 131072)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Blob")
+	}
+
+	kzgCommitment, err := bytesutil.DecodeHexWithLength(sc.KzgCommitment, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgCommitment")
+	}
+
+	kzgProof, err := bytesutil.DecodeHexWithLength(sc.KzgProof, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgProof")
+	}
+
+	header, err := sc.SignedBeaconBlockHeader.ToConsensus()
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SignedBeaconBlockHeader")
+	}
+
+	// decode the commitment inclusion proof
+	var commitmentInclusionProof [][]byte
+	for _, proof := range sc.CommitmentInclusionProof {
+		proofBytes, err := bytesutil.DecodeHexWithLength(proof, 32)
+		if err != nil {
+			return nil, server.NewDecodeError(err, "CommitmentInclusionProof")
+		}
+		commitmentInclusionProof = append(commitmentInclusionProof, proofBytes)
+	}
+
+	bsc := &eth.BlobSidecar{
+		Index:                    index,
+		Blob:                     blob,
+		KzgCommitment:            kzgCommitment,
+		KzgProof:                 kzgProof,
+		SignedBlockHeader:        header,
+		CommitmentInclusionProof: commitmentInclusionProof,
+	}
+
+	return bsc, nil
+}
--- a/api/server/structs/conversions_block.go
+++ b/api/server/structs/conversions_block.go
--- a/api/server/structs/conversions_lightclient.go
+++ b/api/server/structs/conversions_lightclient.go
@@ -3,120 +3,227 @@ package structs
 import (
 	"encoding/json"
 	"fmt"
-	"strconv"

 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/eth/v1"
-	v2 "github.com/prysmaticlabs/prysm/v5/proto/eth/v2"
-	"github.com/prysmaticlabs/prysm/v5/proto/migration"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
+	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
+	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 )

-func LightClientUpdateFromConsensus(update *v2.LightClientUpdate) (*LightClientUpdate, error) {
-	attestedHeader, err := lightClientHeaderContainerToJSON(update.AttestedHeader)
+func LightClientUpdateFromConsensus(update interfaces.LightClientUpdate) (*LightClientUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not marshal attested light client header")
 	}
-	finalizedHeader, err := lightClientHeaderContainerToJSON(update.FinalizedHeader)
+	finalizedHeader, err := lightClientHeaderToJSON(update.FinalizedHeader())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not marshal finalized light client header")
 	}

+	var scBranch [][32]byte
+	var finalityBranch [][32]byte
+	if update.Version() >= version.Electra {
+		scb, err := update.NextSyncCommitteeBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = scb[:]
+		fb, err := update.FinalityBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = fb[:]
+	} else {
+		scb, err := update.NextSyncCommitteeBranch()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = scb[:]
+		fb, err := update.FinalityBranch()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = fb[:]
+	}
+
 	return &LightClientUpdate{
 		AttestedHeader:          attestedHeader,
-		NextSyncCommittee:       SyncCommitteeFromConsensus(migration.V2SyncCommitteeToV1Alpha1(update.NextSyncCommittee)),
-		NextSyncCommitteeBranch: branchToJSON(update.NextSyncCommitteeBranch),
+		NextSyncCommittee:       SyncCommitteeFromConsensus(update.NextSyncCommittee()),
+		NextSyncCommitteeBranch: branchToJSON(scBranch),
 		FinalizedHeader:         finalizedHeader,
-		FinalityBranch:          branchToJSON(update.FinalityBranch),
-		SyncAggregate:           syncAggregateToJSON(update.SyncAggregate),
-		SignatureSlot:           strconv.FormatUint(uint64(update.SignatureSlot), 10),
+		FinalityBranch:          branchToJSON(finalityBranch),
+		SyncAggregate:           SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:           fmt.Sprintf("%d", update.SignatureSlot()),
 	}, nil
 }

-func LightClientFinalityUpdateFromConsensus(update *v2.LightClientFinalityUpdate) (*LightClientFinalityUpdate, error) {
-	attestedHeader, err := lightClientHeaderContainerToJSON(update.AttestedHeader)
+func LightClientFinalityUpdateFromConsensus(update interfaces.LightClientFinalityUpdate) (*LightClientFinalityUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not marshal attested light client header")
 	}
-	finalizedHeader, err := lightClientHeaderContainerToJSON(update.FinalizedHeader)
+	finalizedHeader, err := lightClientHeaderToJSON(update.FinalizedHeader())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not marshal finalized light client header")
 	}

+	var finalityBranch [][32]byte
+	if update.Version() >= version.Electra {
+		b, err := update.FinalityBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = b[:]
+	} else {
+		b, err := update.FinalityBranch()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = b[:]
+	}
+
 	return &LightClientFinalityUpdate{
 		AttestedHeader:  attestedHeader,
 		FinalizedHeader: finalizedHeader,
-		FinalityBranch:  branchToJSON(update.FinalityBranch),
-		SyncAggregate:   syncAggregateToJSON(update.SyncAggregate),
-		SignatureSlot:   strconv.FormatUint(uint64(update.SignatureSlot), 10),
+		FinalityBranch:  branchToJSON(finalityBranch),
+		SyncAggregate:   SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:   fmt.Sprintf("%d", update.SignatureSlot()),
 	}, nil
 }

-func LightClientOptimisticUpdateFromConsensus(update *v2.LightClientOptimisticUpdate) (*LightClientOptimisticUpdate, error) {
-	attestedHeader, err := lightClientHeaderContainerToJSON(update.AttestedHeader)
+func LightClientOptimisticUpdateFromConsensus(update interfaces.LightClientOptimisticUpdate) (*LightClientOptimisticUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not marshal attested light client header")
 	}

 	return &LightClientOptimisticUpdate{
 		AttestedHeader: attestedHeader,
-		SyncAggregate:  syncAggregateToJSON(update.SyncAggregate),
-		SignatureSlot:  strconv.FormatUint(uint64(update.SignatureSlot), 10),
+		SyncAggregate:  SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:  fmt.Sprintf("%d", update.SignatureSlot()),
 	}, nil
 }

-func branchToJSON(branchBytes [][]byte) []string {
+func branchToJSON[S [][32]byte](branchBytes S) []string {
 	if branchBytes == nil {
 		return nil
 	}
 	branch := make([]string, len(branchBytes))
 	for i, root := range branchBytes {
-		branch[i] = hexutil.Encode(root)
+		branch[i] = hexutil.Encode(root[:])
 	}
 	return branch
 }

-func syncAggregateToJSON(input *v1.SyncAggregate) *SyncAggregate {
-	return &SyncAggregate{
-		SyncCommitteeBits:      hexutil.Encode(input.SyncCommitteeBits),
-		SyncCommitteeSignature: hexutil.Encode(input.SyncCommitteeSignature),
-	}
-}
-
-func lightClientHeaderContainerToJSON(container *v2.LightClientHeaderContainer) (json.RawMessage, error) {
-	beacon, err := container.GetBeacon()
-	if err != nil {
-		return nil, errors.Wrap(err, "could not get beacon block header")
+func lightClientHeaderToJSON(header interfaces.LightClientHeader) (json.RawMessage, error) {
+	// In the case that a finalizedHeader is nil.
+	if header == nil {
+		return nil, nil
 	}

-	var header any
+	var result any

-	switch t := (container.Header).(type) {
-	case *v2.LightClientHeaderContainer_HeaderAltair:
-		header = &LightClientHeader{Beacon: BeaconBlockHeaderFromConsensus(migration.V1HeaderToV1Alpha1(beacon))}
-	case *v2.LightClientHeaderContainer_HeaderCapella:
-		execution, err := ExecutionPayloadHeaderCapellaFromConsensus(t.HeaderCapella.Execution)
+	switch v := header.Version(); v {
+	case version.Altair:
+		result = &LightClientHeader{Beacon: BeaconBlockHeaderFromConsensus(header.Beacon())}
+	case version.Capella:
+		exInterface, err := header.Execution()
 		if err != nil {
 			return nil, err
 		}
-		header = &LightClientHeaderCapella{
-			Beacon:          BeaconBlockHeaderFromConsensus(migration.V1HeaderToV1Alpha1(beacon)),
-			Execution:       execution,
-			ExecutionBranch: branchToJSON(t.HeaderCapella.ExecutionBranch),
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderCapella)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderCapella{})
 		}
-	case *v2.LightClientHeaderContainer_HeaderDeneb:
-		execution, err := ExecutionPayloadHeaderDenebFromConsensus(t.HeaderDeneb.Execution)
+		execution, err := ExecutionPayloadHeaderCapellaFromConsensus(ex)
 		if err != nil {
 			return nil, err
 		}
-		header = &LightClientHeaderDeneb{
-			Beacon:          BeaconBlockHeaderFromConsensus(migration.V1HeaderToV1Alpha1(beacon)),
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderCapella{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
 			Execution:       execution,
-			ExecutionBranch: branchToJSON(t.HeaderDeneb.ExecutionBranch),
+			ExecutionBranch: branchToJSON(executionBranch[:]),
+		}
+	case version.Deneb:
+		exInterface, err := header.Execution()
+		if err != nil {
+			return nil, err
+		}
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderDeneb{})
+		}
+		execution, err := ExecutionPayloadHeaderDenebFromConsensus(ex)
+		if err != nil {
+			return nil, err
+		}
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderDeneb{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
+			Execution:       execution,
+			ExecutionBranch: branchToJSON(executionBranch[:]),
+		}
+	case version.Electra:
+		exInterface, err := header.Execution()
+		if err != nil {
+			return nil, err
+		}
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderDeneb{})
+		}
+		execution, err := ExecutionPayloadHeaderElectraFromConsensus(ex)
+		if err != nil {
+			return nil, err
+		}
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderDeneb{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
+			Execution:       execution,
+			ExecutionBranch: branchToJSON(executionBranch[:]),
 		}
 	default:
-		return nil, fmt.Errorf("unsupported header type %T", t)
+		return nil, fmt.Errorf("unsupported header version %s", version.String(v))
 	}

-	return json.Marshal(header)
+	return json.Marshal(result)
+}
+
+func LightClientBootstrapFromConsensus(bootstrap interfaces.LightClientBootstrap) (*LightClientBootstrap, error) {
+	header, err := lightClientHeaderToJSON(bootstrap.Header())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal light client header")
+	}
+
+	var scBranch [][32]byte
+	if bootstrap.Version() >= version.Electra {
+		b, err := bootstrap.CurrentSyncCommitteeBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = b[:]
+	} else {
+		b, err := bootstrap.CurrentSyncCommitteeBranch()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = b[:]
+	}
+
+	return &LightClientBootstrap{
+		Header:                     header,
+		CurrentSyncCommittee:       SyncCommitteeFromConsensus(bootstrap.CurrentSyncCommittee()),
+		CurrentSyncCommitteeBranch: branchToJSON(scBranch),
+	}, nil
 }
--- a/api/server/structs/conversions_state.go
+++ b/api/server/structs/conversions_state.go
@@ -11,6 +11,10 @@ import (

 var errPayloadHeaderNotFound = errors.New("expected payload header not found")

+// ----------------------------------------------------------------------------
+// Phase 0
+// ----------------------------------------------------------------------------
+
 func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -97,6 +101,10 @@ func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error)
 	}, nil
 }

+// ----------------------------------------------------------------------------
+// Altair
+// ----------------------------------------------------------------------------
+
 func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAltair, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -202,6 +210,10 @@ func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAlt
 	}, nil
 }

+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
 func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconStateBellatrix, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -320,6 +332,10 @@ func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconState
 	}, nil
 }

+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
 func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCapella, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -457,6 +473,10 @@ func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCa
 	}, nil
 }

+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
 func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDeneb, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -594,6 +614,10 @@ func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDene
 	}, nil
 }

+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
 func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateElectra, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -674,7 +698,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	if err != nil {
 		return nil, err
 	}
-	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderElectra)
+	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
 	if !ok {
 		return nil, errPayloadHeaderNotFound
 	}
@@ -722,7 +746,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	if err != nil {
 		return nil, err
 	}
-	pbd, err := st.PendingBalanceDeposits()
+	pbd, err := st.PendingDeposits()
 	if err != nil {
 		return nil, err
 	}
@@ -770,7 +794,193 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 		EarliestExitEpoch:             fmt.Sprintf("%d", eee),
 		ConsolidationBalanceToConsume: fmt.Sprintf("%d", cbtc),
 		EarliestConsolidationEpoch:    fmt.Sprintf("%d", ece),
-		PendingBalanceDeposits:        PendingBalanceDepositsFromConsensus(pbd),
+		PendingDeposits:               PendingDepositsFromConsensus(pbd),
+		PendingPartialWithdrawals:     PendingPartialWithdrawalsFromConsensus(ppw),
+		PendingConsolidations:         PendingConsolidationsFromConsensus(pc),
+	}, nil
+}
+
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------
+
+func BeaconStateFuluFromConsensus(st beaconState.BeaconState) (*BeaconStateFulu, error) {
+	srcBr := st.BlockRoots()
+	br := make([]string, len(srcBr))
+	for i, r := range srcBr {
+		br[i] = hexutil.Encode(r)
+	}
+	srcSr := st.StateRoots()
+	sr := make([]string, len(srcSr))
+	for i, r := range srcSr {
+		sr[i] = hexutil.Encode(r)
+	}
+	srcHr, err := st.HistoricalRoots()
+	if err != nil {
+		return nil, err
+	}
+	hr := make([]string, len(srcHr))
+	for i, r := range srcHr {
+		hr[i] = hexutil.Encode(r)
+	}
+	srcVotes := st.Eth1DataVotes()
+	votes := make([]*Eth1Data, len(srcVotes))
+	for i, e := range srcVotes {
+		votes[i] = Eth1DataFromConsensus(e)
+	}
+	srcVals := st.Validators()
+	vals := make([]*Validator, len(srcVals))
+	for i, v := range srcVals {
+		vals[i] = ValidatorFromConsensus(v)
+	}
+	srcBals := st.Balances()
+	bals := make([]string, len(srcBals))
+	for i, b := range srcBals {
+		bals[i] = fmt.Sprintf("%d", b)
+	}
+	srcRm := st.RandaoMixes()
+	rm := make([]string, len(srcRm))
+	for i, m := range srcRm {
+		rm[i] = hexutil.Encode(m)
+	}
+	srcSlashings := st.Slashings()
+	slashings := make([]string, len(srcSlashings))
+	for i, s := range srcSlashings {
+		slashings[i] = fmt.Sprintf("%d", s)
+	}
+	srcPrevPart, err := st.PreviousEpochParticipation()
+	if err != nil {
+		return nil, err
+	}
+	prevPart := make([]string, len(srcPrevPart))
+	for i, p := range srcPrevPart {
+		prevPart[i] = fmt.Sprintf("%d", p)
+	}
+	srcCurrPart, err := st.CurrentEpochParticipation()
+	if err != nil {
+		return nil, err
+	}
+	currPart := make([]string, len(srcCurrPart))
+	for i, p := range srcCurrPart {
+		currPart[i] = fmt.Sprintf("%d", p)
+	}
+	srcIs, err := st.InactivityScores()
+	if err != nil {
+		return nil, err
+	}
+	is := make([]string, len(srcIs))
+	for i, s := range srcIs {
+		is[i] = fmt.Sprintf("%d", s)
+	}
+	currSc, err := st.CurrentSyncCommittee()
+	if err != nil {
+		return nil, err
+	}
+	nextSc, err := st.NextSyncCommittee()
+	if err != nil {
+		return nil, err
+	}
+	execData, err := st.LatestExecutionPayloadHeader()
+	if err != nil {
+		return nil, err
+	}
+	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+	if !ok {
+		return nil, errPayloadHeaderNotFound
+	}
+	payload, err := ExecutionPayloadHeaderElectraFromConsensus(srcPayload)
+	if err != nil {
+		return nil, err
+	}
+	srcHs, err := st.HistoricalSummaries()
+	if err != nil {
+		return nil, err
+	}
+	hs := make([]*HistoricalSummary, len(srcHs))
+	for i, s := range srcHs {
+		hs[i] = HistoricalSummaryFromConsensus(s)
+	}
+	nwi, err := st.NextWithdrawalIndex()
+	if err != nil {
+		return nil, err
+	}
+	nwvi, err := st.NextWithdrawalValidatorIndex()
+	if err != nil {
+		return nil, err
+	}
+	drsi, err := st.DepositRequestsStartIndex()
+	if err != nil {
+		return nil, err
+	}
+	dbtc, err := st.DepositBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	ebtc, err := st.ExitBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	eee, err := st.EarliestExitEpoch()
+	if err != nil {
+		return nil, err
+	}
+	cbtc, err := st.ConsolidationBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	ece, err := st.EarliestConsolidationEpoch()
+	if err != nil {
+		return nil, err
+	}
+	pbd, err := st.PendingDeposits()
+	if err != nil {
+		return nil, err
+	}
+	ppw, err := st.PendingPartialWithdrawals()
+	if err != nil {
+		return nil, err
+	}
+	pc, err := st.PendingConsolidations()
+	if err != nil {
+		return nil, err
+	}
+
+	return &BeaconStateFulu{
+		GenesisTime:                   fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisValidatorsRoot:         hexutil.Encode(st.GenesisValidatorsRoot()),
+		Slot:                          fmt.Sprintf("%d", st.Slot()),
+		Fork:                          ForkFromConsensus(st.Fork()),
+		LatestBlockHeader:             BeaconBlockHeaderFromConsensus(st.LatestBlockHeader()),
+		BlockRoots:                    br,
+		StateRoots:                    sr,
+		HistoricalRoots:               hr,
+		Eth1Data:                      Eth1DataFromConsensus(st.Eth1Data()),
+		Eth1DataVotes:                 votes,
+		Eth1DepositIndex:              fmt.Sprintf("%d", st.Eth1DepositIndex()),
+		Validators:                    vals,
+		Balances:                      bals,
+		RandaoMixes:                   rm,
+		Slashings:                     slashings,
+		PreviousEpochParticipation:    prevPart,
+		CurrentEpochParticipation:     currPart,
+		JustificationBits:             hexutil.Encode(st.JustificationBits()),
+		PreviousJustifiedCheckpoint:   CheckpointFromConsensus(st.PreviousJustifiedCheckpoint()),
+		CurrentJustifiedCheckpoint:    CheckpointFromConsensus(st.CurrentJustifiedCheckpoint()),
+		FinalizedCheckpoint:           CheckpointFromConsensus(st.FinalizedCheckpoint()),
+		InactivityScores:              is,
+		CurrentSyncCommittee:          SyncCommitteeFromConsensus(currSc),
+		NextSyncCommittee:             SyncCommitteeFromConsensus(nextSc),
+		LatestExecutionPayloadHeader:  payload,
+		NextWithdrawalIndex:           fmt.Sprintf("%d", nwi),
+		NextWithdrawalValidatorIndex:  fmt.Sprintf("%d", nwvi),
+		HistoricalSummaries:           hs,
+		DepositRequestsStartIndex:     fmt.Sprintf("%d", drsi),
+		DepositBalanceToConsume:       fmt.Sprintf("%d", dbtc),
+		ExitBalanceToConsume:          fmt.Sprintf("%d", ebtc),
+		EarliestExitEpoch:             fmt.Sprintf("%d", eee),
+		ConsolidationBalanceToConsume: fmt.Sprintf("%d", cbtc),
+		EarliestConsolidationEpoch:    fmt.Sprintf("%d", ece),
+		PendingDeposits:               PendingDepositsFromConsensus(pbd),
 		PendingPartialWithdrawals:     PendingPartialWithdrawalsFromConsensus(ppw),
 		PendingConsolidations:         PendingConsolidationsFromConsensus(pc),
 	}, nil
--- a/api/server/structs/endpoints_beacon.go
+++ b/api/server/structs/endpoints_beacon.go
@@ -21,11 +21,12 @@ type GetCommitteesResponse struct {
 }

 type ListAttestationsResponse struct {
-	Data []*Attestation `json:"data"`
+	Version string          `json:"version,omitempty"`
+	Data    json.RawMessage `json:"data"`
 }

 type SubmitAttestationsRequest struct {
-	Data []*Attestation `json:"data"`
+	Data json.RawMessage `json:"data"`
 }

 type ListVoluntaryExitsResponse struct {
@@ -133,6 +134,13 @@ type GetBlockAttestationsResponse struct {
 	Data                []*Attestation `json:"data"`
 }

+type GetBlockAttestationsV2Response struct {
+	Version             string          `json:"version"`
+	ExecutionOptimistic bool            `json:"execution_optimistic"`
+	Finalized           bool            `json:"finalized"`
+	Data                json.RawMessage `json:"data"` // Accepts both `Attestation` and `AttestationElectra` types
+}
+
 type GetStateRootResponse struct {
 	ExecutionOptimistic bool       `json:"execution_optimistic"`
 	Finalized           bool       `json:"finalized"`
@@ -169,7 +177,8 @@ type BLSToExecutionChangesPoolResponse struct {
 }

 type GetAttesterSlashingsResponse struct {
-	Data []*AttesterSlashing `json:"data"`
+	Version string          `json:"version,omitempty"`
+	Data    json.RawMessage `json:"data"` // Accepts both `[]*AttesterSlashing` and `[]*AttesterSlashingElectra` types
 }

 type GetProposerSlashingsResponse struct {
--- a/api/server/structs/endpoints_blob.go
+++ b/api/server/structs/endpoints_blob.go
@@ -1,7 +1,10 @@
 package structs

 type SidecarsResponse struct {
-	Data []*Sidecar `json:"data"`
+	Version             string     `json:"version"`
+	Data                []*Sidecar `json:"data"`
+	ExecutionOptimistic bool       `json:"execution_optimistic"`
+	Finalized           bool       `json:"finalized"`
 }

 type Sidecar struct {
@@ -12,3 +15,12 @@ type Sidecar struct {
 	KzgProof                 string                   `json:"kzg_proof"`
 	CommitmentInclusionProof []string                 `json:"kzg_commitment_inclusion_proof"`
 }
+
+type BlobSidecars struct {
+	Sidecars []*Sidecar `json:"sidecars"`
+}
+
+type PublishBlobsRequest struct {
+	BlobSidecars *BlobSidecars `json:"blob_sidecars"`
+	BlockRoot    string        `json:"block_root"`
+}
--- a/api/server/structs/endpoints_validator.go
+++ b/api/server/structs/endpoints_validator.go
@@ -7,7 +7,8 @@ import (
 )

 type AggregateAttestationResponse struct {
-	Data *Attestation `json:"data"`
+	Version string          `json:"version,omitempty"`
+	Data    json.RawMessage `json:"data"`
 }

 type SubmitContributionAndProofsRequest struct {
@@ -15,7 +16,7 @@ type SubmitContributionAndProofsRequest struct {
 }

 type SubmitAggregateAndProofsRequest struct {
-	Data []*SignedAggregateAttestationAndProof `json:"data"`
+	Data []json.RawMessage `json:"data"`
 }

 type SubmitSyncCommitteeSubscriptionsRequest struct {
--- a/api/server/structs/other.go
+++ b/api/server/structs/other.go
@@ -257,9 +257,12 @@ type ConsolidationRequest struct {
 	TargetPubkey  string `json:"target_pubkey"`
 }

-type PendingBalanceDeposit struct {
-	Index  string `json:"index"`
-	Amount string `json:"amount"`
+type PendingDeposit struct {
+	Pubkey                string `json:"pubkey"`
+	WithdrawalCredentials string `json:"withdrawal_credentials"`
+	Amount                string `json:"amount"`
+	Signature             string `json:"signature"`
+	Slot                  string `json:"slot"`
 }

 type PendingPartialWithdrawal struct {
--- a/api/server/structs/state.go
+++ b/api/server/structs/state.go
@@ -142,41 +142,81 @@ type BeaconStateDeneb struct {
 }

 type BeaconStateElectra struct {
-	GenesisTime                   string                         `json:"genesis_time"`
-	GenesisValidatorsRoot         string                         `json:"genesis_validators_root"`
-	Slot                          string                         `json:"slot"`
-	Fork                          *Fork                          `json:"fork"`
-	LatestBlockHeader             *BeaconBlockHeader             `json:"latest_block_header"`
-	BlockRoots                    []string                       `json:"block_roots"`
-	StateRoots                    []string                       `json:"state_roots"`
-	HistoricalRoots               []string                       `json:"historical_roots"`
-	Eth1Data                      *Eth1Data                      `json:"eth1_data"`
-	Eth1DataVotes                 []*Eth1Data                    `json:"eth1_data_votes"`
-	Eth1DepositIndex              string                         `json:"eth1_deposit_index"`
-	Validators                    []*Validator                   `json:"validators"`
-	Balances                      []string                       `json:"balances"`
-	RandaoMixes                   []string                       `json:"randao_mixes"`
-	Slashings                     []string                       `json:"slashings"`
-	PreviousEpochParticipation    []string                       `json:"previous_epoch_participation"`
-	CurrentEpochParticipation     []string                       `json:"current_epoch_participation"`
-	JustificationBits             string                         `json:"justification_bits"`
-	PreviousJustifiedCheckpoint   *Checkpoint                    `json:"previous_justified_checkpoint"`
-	CurrentJustifiedCheckpoint    *Checkpoint                    `json:"current_justified_checkpoint"`
-	FinalizedCheckpoint           *Checkpoint                    `json:"finalized_checkpoint"`
-	InactivityScores              []string                       `json:"inactivity_scores"`
-	CurrentSyncCommittee          *SyncCommittee                 `json:"current_sync_committee"`
-	NextSyncCommittee             *SyncCommittee                 `json:"next_sync_committee"`
-	LatestExecutionPayloadHeader  *ExecutionPayloadHeaderElectra `json:"latest_execution_payload_header"`
-	NextWithdrawalIndex           string                         `json:"next_withdrawal_index"`
-	NextWithdrawalValidatorIndex  string                         `json:"next_withdrawal_validator_index"`
-	HistoricalSummaries           []*HistoricalSummary           `json:"historical_summaries"`
-	DepositRequestsStartIndex     string                         `json:"deposit_requests_start_index"`
-	DepositBalanceToConsume       string                         `json:"deposit_balance_to_consume"`
-	ExitBalanceToConsume          string                         `json:"exit_balance_to_consume"`
-	EarliestExitEpoch             string                         `json:"earliest_exit_epoch"`
-	ConsolidationBalanceToConsume string                         `json:"consolidation_balance_to_consume"`
-	EarliestConsolidationEpoch    string                         `json:"earliest_consolidation_epoch"`
-	PendingBalanceDeposits        []*PendingBalanceDeposit       `json:"pending_balance_deposits"`
-	PendingPartialWithdrawals     []*PendingPartialWithdrawal    `json:"pending_partial_withdrawals"`
-	PendingConsolidations         []*PendingConsolidation        `json:"pending_consolidations"`
+	GenesisTime                   string                       `json:"genesis_time"`
+	GenesisValidatorsRoot         string                       `json:"genesis_validators_root"`
+	Slot                          string                       `json:"slot"`
+	Fork                          *Fork                        `json:"fork"`
+	LatestBlockHeader             *BeaconBlockHeader           `json:"latest_block_header"`
+	BlockRoots                    []string                     `json:"block_roots"`
+	StateRoots                    []string                     `json:"state_roots"`
+	HistoricalRoots               []string                     `json:"historical_roots"`
+	Eth1Data                      *Eth1Data                    `json:"eth1_data"`
+	Eth1DataVotes                 []*Eth1Data                  `json:"eth1_data_votes"`
+	Eth1DepositIndex              string                       `json:"eth1_deposit_index"`
+	Validators                    []*Validator                 `json:"validators"`
+	Balances                      []string                     `json:"balances"`
+	RandaoMixes                   []string                     `json:"randao_mixes"`
+	Slashings                     []string                     `json:"slashings"`
+	PreviousEpochParticipation    []string                     `json:"previous_epoch_participation"`
+	CurrentEpochParticipation     []string                     `json:"current_epoch_participation"`
+	JustificationBits             string                       `json:"justification_bits"`
+	PreviousJustifiedCheckpoint   *Checkpoint                  `json:"previous_justified_checkpoint"`
+	CurrentJustifiedCheckpoint    *Checkpoint                  `json:"current_justified_checkpoint"`
+	FinalizedCheckpoint           *Checkpoint                  `json:"finalized_checkpoint"`
+	InactivityScores              []string                     `json:"inactivity_scores"`
+	CurrentSyncCommittee          *SyncCommittee               `json:"current_sync_committee"`
+	NextSyncCommittee             *SyncCommittee               `json:"next_sync_committee"`
+	LatestExecutionPayloadHeader  *ExecutionPayloadHeaderDeneb `json:"latest_execution_payload_header"`
+	NextWithdrawalIndex           string                       `json:"next_withdrawal_index"`
+	NextWithdrawalValidatorIndex  string                       `json:"next_withdrawal_validator_index"`
+	HistoricalSummaries           []*HistoricalSummary         `json:"historical_summaries"`
+	DepositRequestsStartIndex     string                       `json:"deposit_requests_start_index"`
+	DepositBalanceToConsume       string                       `json:"deposit_balance_to_consume"`
+	ExitBalanceToConsume          string                       `json:"exit_balance_to_consume"`
+	EarliestExitEpoch             string                       `json:"earliest_exit_epoch"`
+	ConsolidationBalanceToConsume string                       `json:"consolidation_balance_to_consume"`
+	EarliestConsolidationEpoch    string                       `json:"earliest_consolidation_epoch"`
+	PendingDeposits               []*PendingDeposit            `json:"pending_deposits"`
+	PendingPartialWithdrawals     []*PendingPartialWithdrawal  `json:"pending_partial_withdrawals"`
+	PendingConsolidations         []*PendingConsolidation      `json:"pending_consolidations"`
+}
+
+type BeaconStateFulu struct {
+	GenesisTime                   string                       `json:"genesis_time"`
+	GenesisValidatorsRoot         string                       `json:"genesis_validators_root"`
+	Slot                          string                       `json:"slot"`
+	Fork                          *Fork                        `json:"fork"`
+	LatestBlockHeader             *BeaconBlockHeader           `json:"latest_block_header"`
+	BlockRoots                    []string                     `json:"block_roots"`
+	StateRoots                    []string                     `json:"state_roots"`
+	HistoricalRoots               []string                     `json:"historical_roots"`
+	Eth1Data                      *Eth1Data                    `json:"eth1_data"`
+	Eth1DataVotes                 []*Eth1Data                  `json:"eth1_data_votes"`
+	Eth1DepositIndex              string                       `json:"eth1_deposit_index"`
+	Validators                    []*Validator                 `json:"validators"`
+	Balances                      []string                     `json:"balances"`
+	RandaoMixes                   []string                     `json:"randao_mixes"`
+	Slashings                     []string                     `json:"slashings"`
+	PreviousEpochParticipation    []string                     `json:"previous_epoch_participation"`
+	CurrentEpochParticipation     []string                     `json:"current_epoch_participation"`
+	JustificationBits             string                       `json:"justification_bits"`
+	PreviousJustifiedCheckpoint   *Checkpoint                  `json:"previous_justified_checkpoint"`
+	CurrentJustifiedCheckpoint    *Checkpoint                  `json:"current_justified_checkpoint"`
+	FinalizedCheckpoint           *Checkpoint                  `json:"finalized_checkpoint"`
+	InactivityScores              []string                     `json:"inactivity_scores"`
+	CurrentSyncCommittee          *SyncCommittee               `json:"current_sync_committee"`
+	NextSyncCommittee             *SyncCommittee               `json:"next_sync_committee"`
+	LatestExecutionPayloadHeader  *ExecutionPayloadHeaderDeneb `json:"latest_execution_payload_header"`
+	NextWithdrawalIndex           string                       `json:"next_withdrawal_index"`
+	NextWithdrawalValidatorIndex  string                       `json:"next_withdrawal_validator_index"`
+	HistoricalSummaries           []*HistoricalSummary         `json:"historical_summaries"`
+	DepositRequestsStartIndex     string                       `json:"deposit_requests_start_index"`
+	DepositBalanceToConsume       string                       `json:"deposit_balance_to_consume"`
+	ExitBalanceToConsume          string                       `json:"exit_balance_to_consume"`
+	EarliestExitEpoch             string                       `json:"earliest_exit_epoch"`
+	ConsolidationBalanceToConsume string                       `json:"consolidation_balance_to_consume"`
+	EarliestConsolidationEpoch    string                       `json:"earliest_consolidation_epoch"`
+	PendingDeposits               []*PendingDeposit            `json:"pending_deposits"`
+	PendingPartialWithdrawals     []*PendingPartialWithdrawal  `json:"pending_partial_withdrawals"`
+	PendingConsolidations         []*PendingConsolidation      `json:"pending_consolidations"`
 }
--- a/async/event/BUILD.bazel
+++ b/async/event/BUILD.bazel
@@ -4,26 +4,25 @@ go_library(
    name = "go_default_library",
    srcs = [
        "feed.go",
+        "interface.go",
        "subscription.go",
    ],
    importpath = "github.com/prysmaticlabs/prysm/v5/async/event",
    visibility = ["//visibility:public"],
-    deps = ["//time/mclock:go_default_library"],
+    deps = [
+        "//time/mclock:go_default_library",
+        "@com_github_ethereum_go_ethereum//event:go_default_library",
+    ],
 )

 go_test(
    name = "go_default_test",
    size = "small",
    srcs = [
-        "example_feed_test.go",
        "example_scope_test.go",
        "example_subscription_test.go",
-        "feed_test.go",
        "subscription_test.go",
    ],
    embed = [":go_default_library"],
-    deps = [
-        "//testing/assert:go_default_library",
-        "//testing/require:go_default_library",
-    ],
+    deps = ["//testing/require:go_default_library"],
 )
--- a/async/event/example_feed_test.go
+++ b/async/event/example_feed_test.go
@@ -1,73 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package event_test
-
-import (
-	"fmt"
-
-	"github.com/prysmaticlabs/prysm/v5/async/event"
-)
-
-func ExampleFeed_acknowledgedEvents() {
-	// This example shows how the return value of Send can be used for request/reply
-	// interaction between event consumers and producers.
-	var feed event.Feed
-	type ackedEvent struct {
-		i   int
-		ack chan<- struct{}
-	}
-
-	// Consumers wait for events on the feed and acknowledge processing.
-	done := make(chan struct{})
-	defer close(done)
-	for i := 0; i < 3; i++ {
-		ch := make(chan ackedEvent, 100)
-		sub := feed.Subscribe(ch)
-		go func() {
-			defer sub.Unsubscribe()
-			for {
-				select {
-				case ev := <-ch:
-					fmt.Println(ev.i) // "process" the event
-					ev.ack <- struct{}{}
-				case <-done:
-					return
-				}
-			}
-		}()
-	}
-
-	// The producer sends values of type ackedEvent with increasing values of i.
-	// It waits for all consumers to acknowledge before sending the next event.
-	for i := 0; i < 3; i++ {
-		acksignal := make(chan struct{})
-		n := feed.Send(ackedEvent{i, acksignal})
-		for ack := 0; ack < n; ack++ {
-			<-acksignal
-		}
-	}
-	// Output:
-	// 0
-	// 0
-	// 0
-	// 1
-	// 1
-	// 1
-	// 2
-	// 2
-	// 2
-}
--- a/async/event/feed.go
+++ b/async/event/feed.go
@@ -14,241 +14,12 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

-// Package event contains an event feed implementation for process communication.
 package event

 import (
-	"errors"
-	"reflect"
-	"slices"
-	"sync"
+	geth_event "github.com/ethereum/go-ethereum/event"
 )

-var errBadChannel = errors.New("event: Subscribe argument does not have sendable channel type")
-
-// Feed implements one-to-many subscriptions where the carrier of events is a channel.
-// Values sent to a Feed are delivered to all subscribed channels simultaneously.
-//
-// Feeds can only be used with a single type. The type is determined by the first Send or
-// Subscribe operation. Subsequent calls to these methods panic if the type does not
-// match.
-//
-// The zero value is ready to use.
-type Feed struct {
-	once      sync.Once        // ensures that init only runs once
-	sendLock  chan struct{}    // sendLock has a one-element buffer and is empty when held.It protects sendCases.
-	removeSub chan interface{} // interrupts Send
-	sendCases caseList         // the active set of select cases used by Send
-
-	// The inbox holds newly subscribed channels until they are added to sendCases.
-	mu    sync.Mutex
-	inbox caseList
-	etype reflect.Type
-}
-
-// This is the index of the first actual subscription channel in sendCases.
-// sendCases[0] is a SelectRecv case for the removeSub channel.
-const firstSubSendCase = 1
-
-type feedTypeError struct {
-	got, want reflect.Type
-	op        string
-}
-
-func (e feedTypeError) Error() string {
-	return "event: wrong type in " + e.op + " got " + e.got.String() + ", want " + e.want.String()
-}
-
-func (f *Feed) init() {
-	f.removeSub = make(chan interface{})
-	f.sendLock = make(chan struct{}, 1)
-	f.sendLock <- struct{}{}
-	f.sendCases = caseList{{Chan: reflect.ValueOf(f.removeSub), Dir: reflect.SelectRecv}}
-}
-
-// Subscribe adds a channel to the feed. Future sends will be delivered on the channel
-// until the subscription is canceled. All channels added must have the same element type.
-//
-// The channel should have ample buffer space to avoid blocking other subscribers.
-// Slow subscribers are not dropped.
-func (f *Feed) Subscribe(channel interface{}) Subscription {
-	f.once.Do(f.init)
-
-	chanval := reflect.ValueOf(channel)
-	chantyp := chanval.Type()
-	if chantyp.Kind() != reflect.Chan || chantyp.ChanDir()&reflect.SendDir == 0 {
-		panic(errBadChannel)
-	}
-	sub := &feedSub{feed: f, channel: chanval, err: make(chan error, 1)}
-
-	f.mu.Lock()
-	defer f.mu.Unlock()
-	if !f.typecheck(chantyp.Elem()) {
-		panic(feedTypeError{op: "Subscribe", got: chantyp, want: reflect.ChanOf(reflect.SendDir, f.etype)})
-	}
-	// Add the select case to the inbox.
-	// The next Send will add it to f.sendCases.
-	cas := reflect.SelectCase{Dir: reflect.SelectSend, Chan: chanval}
-	f.inbox = append(f.inbox, cas)
-	return sub
-}
-
-// note: callers must hold f.mu
-func (f *Feed) typecheck(typ reflect.Type) bool {
-	if f.etype == nil {
-		f.etype = typ
-		return true
-	}
-	// In the event the feed's type is an actual interface, we
-	// perform an interface conformance check here.
-	if f.etype.Kind() == reflect.Interface && typ.Implements(f.etype) {
-		return true
-	}
-	return f.etype == typ
-}
-
-func (f *Feed) remove(sub *feedSub) {
-	// Delete from inbox first, which covers channels
-	// that have not been added to f.sendCases yet.
-	ch := sub.channel.Interface()
-	f.mu.Lock()
-	index := f.inbox.find(ch)
-	if index != -1 {
-		f.inbox = f.inbox.delete(index)
-		f.mu.Unlock()
-		return
-	}
-	f.mu.Unlock()
-
-	select {
-	case f.removeSub <- ch:
-		// Send will remove the channel from f.sendCases.
-	case <-f.sendLock:
-		// No Send is in progress, delete the channel now that we have the send lock.
-		f.sendCases = f.sendCases.delete(f.sendCases.find(ch))
-		f.sendLock <- struct{}{}
-	}
-}
-
-// Send delivers to all subscribed channels simultaneously.
-// It returns the number of subscribers that the value was sent to.
-func (f *Feed) Send(value interface{}) (nsent int) {
-	rvalue := reflect.ValueOf(value)
-
-	f.once.Do(f.init)
-	<-f.sendLock
-
-	// Add new cases from the inbox after taking the send lock.
-	f.mu.Lock()
-	f.sendCases = append(f.sendCases, f.inbox...)
-	f.inbox = nil
-
-	if !f.typecheck(rvalue.Type()) {
-		f.sendLock <- struct{}{}
-		f.mu.Unlock()
-		panic(feedTypeError{op: "Send", got: rvalue.Type(), want: f.etype})
-	}
-	f.mu.Unlock()
-
-	// Set the sent value on all channels.
-	for i := firstSubSendCase; i < len(f.sendCases); i++ {
-		f.sendCases[i].Send = rvalue
-	}
-
-	// Send until all channels except removeSub have been chosen. 'cases' tracks a prefix
-	// of sendCases. When a send succeeds, the corresponding case moves to the end of
-	// 'cases' and it shrinks by one element.
-	cases := f.sendCases
-	for {
-		// Fast path: try sending without blocking before adding to the select set.
-		// This should usually succeed if subscribers are fast enough and have free
-		// buffer space.
-		for i := firstSubSendCase; i < len(cases); i++ {
-			if cases[i].Chan.TrySend(rvalue) {
-				nsent++
-				cases = cases.deactivate(i)
-				i--
-			}
-		}
-		if len(cases) == firstSubSendCase {
-			break
-		}
-		// Select on all the receivers, waiting for them to unblock.
-		chosen, recv, _ := reflect.Select(cases)
-		if chosen == 0 /* <-f.removeSub */ {
-			index := f.sendCases.find(recv.Interface())
-			f.sendCases = f.sendCases.delete(index)
-			if index >= 0 && index < len(cases) {
-				// Shrink 'cases' too because the removed case was still active.
-				cases = f.sendCases[:len(cases)-1]
-			}
-		} else {
-			cases = cases.deactivate(chosen)
-			nsent++
-		}
-	}
-
-	// Forget about the sent value and hand off the send lock.
-	for i := firstSubSendCase; i < len(f.sendCases); i++ {
-		f.sendCases[i].Send = reflect.Value{}
-	}
-	f.sendLock <- struct{}{}
-	return nsent
-}
-
-type feedSub struct {
-	feed    *Feed
-	channel reflect.Value
-	errOnce sync.Once
-	err     chan error
-}
-
-// Unsubscribe remove feed subscription.
-func (sub *feedSub) Unsubscribe() {
-	sub.errOnce.Do(func() {
-		sub.feed.remove(sub)
-		close(sub.err)
-	})
-}
-
-// Err returns error channel.
-func (sub *feedSub) Err() <-chan error {
-	return sub.err
-}
-
-type caseList []reflect.SelectCase
-
-// find returns the index of a case containing the given channel.
-func (cs caseList) find(channel interface{}) int {
-	return slices.IndexFunc(cs, func(selectCase reflect.SelectCase) bool {
-		return selectCase.Chan.Interface() == channel
-	})
-}
-
-// delete removes the given case from cs.
-func (cs caseList) delete(index int) caseList {
-	return append(cs[:index], cs[index+1:]...)
-}
-
-// deactivate moves the case at index into the non-accessible portion of the cs slice.
-func (cs caseList) deactivate(index int) caseList {
-	last := len(cs) - 1
-	cs[index], cs[last] = cs[last], cs[index]
-	return cs[:last]
-}
-
-// func (cs caseList) String() string {
-//     s := "["
-//     for i, cas := range cs {
-//             if i != 0 {
-//                     s += ", "
-//             }
-//             switch cas.Dir {
-//             case reflect.SelectSend:
-//                     s += fmt.Sprintf("%v<-", cas.Chan.Interface())
-//             case reflect.SelectRecv:
-//                     s += fmt.Sprintf("<-%v", cas.Chan.Interface())
-//             }
-//     }
-//     return s + "]"
-// }
+// Feed is a re-export of the go-ethereum event feed.
+type Feed = geth_event.Feed
+type Subscription = geth_event.Subscription
--- a/async/event/feed_test.go
+++ b/async/event/feed_test.go
@@ -1,509 +0,0 @@
-// Copyright 2016 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package event
-
-import (
-	"fmt"
-	"reflect"
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-)
-
-func TestFeedPanics(t *testing.T) {
-	{
-		var f Feed
-		f.Send(2)
-		want := feedTypeError{op: "Send", got: reflect.TypeOf(uint64(0)), want: reflect.TypeOf(0)}
-		assert.NoError(t, checkPanic(want, func() { f.Send(uint64(2)) }))
-		// Validate it doesn't deadlock.
-		assert.NoError(t, checkPanic(want, func() { f.Send(uint64(2)) }))
-	}
-	{
-		var f Feed
-		ch := make(chan int)
-		f.Subscribe(ch)
-		want := feedTypeError{op: "Send", got: reflect.TypeOf(uint64(0)), want: reflect.TypeOf(0)}
-		assert.NoError(t, checkPanic(want, func() { f.Send(uint64(2)) }))
-	}
-	{
-		var f Feed
-		f.Send(2)
-		want := feedTypeError{op: "Subscribe", got: reflect.TypeOf(make(chan uint64)), want: reflect.TypeOf(make(chan<- int))}
-		assert.NoError(t, checkPanic(want, func() { f.Subscribe(make(chan uint64)) }))
-	}
-	{
-		var f Feed
-		assert.NoError(t, checkPanic(errBadChannel, func() { f.Subscribe(make(<-chan int)) }))
-	}
-	{
-		var f Feed
-		assert.NoError(t, checkPanic(errBadChannel, func() { f.Subscribe(0) }))
-	}
-}
-
-func checkPanic(want error, fn func()) (err error) {
-	defer func() {
-		panicResult := recover()
-		if panicResult == nil {
-			err = fmt.Errorf("didn't panic")
-		} else if !reflect.DeepEqual(panicResult, want) {
-			err = fmt.Errorf("panicked with wrong error: got %q, want %q", panicResult, want)
-		}
-	}()
-	fn()
-	return nil
-}
-
-func TestFeed(t *testing.T) {
-	var feed Feed
-	var done, subscribed sync.WaitGroup
-	subscriber := func(i int) {
-		defer done.Done()
-
-		subchan := make(chan int)
-		sub := feed.Subscribe(subchan)
-		timeout := time.NewTimer(2 * time.Second)
-		subscribed.Done()
-
-		select {
-		case v := <-subchan:
-			if v != 1 {
-				t.Errorf("%d: received value %d, want 1", i, v)
-			}
-		case <-timeout.C:
-			t.Errorf("%d: receive timeout", i)
-		}
-
-		sub.Unsubscribe()
-		select {
-		case _, ok := <-sub.Err():
-			if ok {
-				t.Errorf("%d: error channel not closed after unsubscribe", i)
-			}
-		case <-timeout.C:
-			t.Errorf("%d: unsubscribe timeout", i)
-		}
-	}
-
-	const n = 1000
-	done.Add(n)
-	subscribed.Add(n)
-	for i := 0; i < n; i++ {
-		go subscriber(i)
-	}
-	subscribed.Wait()
-	if nsent := feed.Send(1); nsent != n {
-		t.Errorf("first send delivered %d times, want %d", nsent, n)
-	}
-	if nsent := feed.Send(2); nsent != 0 {
-		t.Errorf("second send delivered %d times, want 0", nsent)
-	}
-	done.Wait()
-}
-
-func TestFeedSubscribeSameChannel(t *testing.T) {
-	var (
-		feed Feed
-		done sync.WaitGroup
-		ch   = make(chan int)
-		sub1 = feed.Subscribe(ch)
-		sub2 = feed.Subscribe(ch)
-		_    = feed.Subscribe(ch)
-	)
-	expectSends := func(value, n int) {
-		if nsent := feed.Send(value); nsent != n {
-			t.Errorf("send delivered %d times, want %d", nsent, n)
-		}
-		done.Done()
-	}
-	expectRecv := func(wantValue, n int) {
-		for i := 0; i < n; i++ {
-			if v := <-ch; v != wantValue {
-				t.Errorf("received %d, want %d", v, wantValue)
-			}
-		}
-	}
-
-	done.Add(1)
-	go expectSends(1, 3)
-	expectRecv(1, 3)
-	done.Wait()
-
-	sub1.Unsubscribe()
-
-	done.Add(1)
-	go expectSends(2, 2)
-	expectRecv(2, 2)
-	done.Wait()
-
-	sub2.Unsubscribe()
-
-	done.Add(1)
-	go expectSends(3, 1)
-	expectRecv(3, 1)
-	done.Wait()
-}
-
-func TestFeedSubscribeBlockedPost(_ *testing.T) {
-	var (
-		feed   Feed
-		nsends = 2000
-		ch1    = make(chan int)
-		ch2    = make(chan int)
-		wg     sync.WaitGroup
-	)
-	defer wg.Wait()
-
-	feed.Subscribe(ch1)
-	wg.Add(nsends)
-	for i := 0; i < nsends; i++ {
-		go func() {
-			feed.Send(99)
-			wg.Done()
-		}()
-	}
-
-	sub2 := feed.Subscribe(ch2)
-	defer sub2.Unsubscribe()
-
-	// We're done when ch1 has received N times.
-	// The number of receives on ch2 depends on scheduling.
-	for i := 0; i < nsends; {
-		select {
-		case <-ch1:
-			i++
-		case <-ch2:
-		}
-	}
-}
-
-func TestFeedUnsubscribeBlockedPost(_ *testing.T) {
-	var (
-		feed   Feed
-		nsends = 200
-		chans  = make([]chan int, 2000)
-		subs   = make([]Subscription, len(chans))
-		bchan  = make(chan int)
-		bsub   = feed.Subscribe(bchan)
-		wg     sync.WaitGroup
-	)
-	for i := range chans {
-		chans[i] = make(chan int, nsends)
-	}
-
-	// Queue up some Sends. None of these can make progress while bchan isn't read.
-	wg.Add(nsends)
-	for i := 0; i < nsends; i++ {
-		go func() {
-			feed.Send(99)
-			wg.Done()
-		}()
-	}
-	// Subscribe the other channels.
-	for i, ch := range chans {
-		subs[i] = feed.Subscribe(ch)
-	}
-	// Unsubscribe them again.
-	for _, sub := range subs {
-		sub.Unsubscribe()
-	}
-	// Unblock the Sends.
-	bsub.Unsubscribe()
-	wg.Wait()
-}
-
-// Checks that unsubscribing a channel during Send works even if that
-// channel has already been sent on.
-func TestFeedUnsubscribeSentChan(_ *testing.T) {
-	var (
-		feed Feed
-		ch1  = make(chan int)
-		ch2  = make(chan int)
-		sub1 = feed.Subscribe(ch1)
-		sub2 = feed.Subscribe(ch2)
-		wg   sync.WaitGroup
-	)
-	defer sub2.Unsubscribe()
-
-	wg.Add(1)
-	go func() {
-		feed.Send(0)
-		wg.Done()
-	}()
-
-	// Wait for the value on ch1.
-	<-ch1
-	// Unsubscribe ch1, removing it from the send cases.
-	sub1.Unsubscribe()
-
-	// Receive ch2, finishing Send.
-	<-ch2
-	wg.Wait()
-
-	// Send again. This should send to ch2 only, so the wait group will unblock
-	// as soon as a value is received on ch2.
-	wg.Add(1)
-	go func() {
-		feed.Send(0)
-		wg.Done()
-	}()
-	<-ch2
-	wg.Wait()
-}
-
-func TestFeedUnsubscribeFromInbox(t *testing.T) {
-	var (
-		feed Feed
-		ch1  = make(chan int)
-		ch2  = make(chan int)
-		sub1 = feed.Subscribe(ch1)
-		sub2 = feed.Subscribe(ch1)
-		sub3 = feed.Subscribe(ch2)
-	)
-	assert.Equal(t, 3, len(feed.inbox))
-	assert.Equal(t, 1, len(feed.sendCases), "sendCases is non-empty after unsubscribe")
-
-	sub1.Unsubscribe()
-	sub2.Unsubscribe()
-	sub3.Unsubscribe()
-	assert.Equal(t, 0, len(feed.inbox), "Inbox is non-empty after unsubscribe")
-	assert.Equal(t, 1, len(feed.sendCases), "sendCases is non-empty after unsubscribe")
-}
-
-func BenchmarkFeedSend1000(b *testing.B) {
-	var (
-		done  sync.WaitGroup
-		feed  Feed
-		nsubs = 1000
-	)
-	subscriber := func(ch <-chan int) {
-		for i := 0; i < b.N; i++ {
-			<-ch
-		}
-		done.Done()
-	}
-	done.Add(nsubs)
-	for i := 0; i < nsubs; i++ {
-		ch := make(chan int, 200)
-		feed.Subscribe(ch)
-		go subscriber(ch)
-	}
-
-	// The actual benchmark.
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		if feed.Send(i) != nsubs {
-			panic("wrong number of sends")
-		}
-	}
-
-	b.StopTimer()
-	done.Wait()
-}
-
-func TestFeed_Send(t *testing.T) {
-	tests := []struct {
-		name        string
-		evFeed      *Feed
-		testSetup   func(fd *Feed, t *testing.T, o interface{})
-		obj         interface{}
-		expectPanic bool
-	}{
-		{
-			name:   "normal struct",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeedWithPointer, 1)
-				fd.Subscribe(testChan)
-			},
-			obj: testFeedWithPointer{
-				a: new(uint64),
-				b: new(string),
-			},
-			expectPanic: false,
-		},
-		{
-			name:   "un-implemented interface",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeedIface, 1)
-				fd.Subscribe(testChan)
-			},
-			obj: testFeedWithPointer{
-				a: new(uint64),
-				b: new(string),
-			},
-			expectPanic: true,
-		},
-		{
-			name:   "semi-implemented interface",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeedIface, 1)
-				fd.Subscribe(testChan)
-			},
-			obj: testFeed2{
-				a: 0,
-				b: "",
-				c: []byte{'A'},
-			},
-			expectPanic: true,
-		},
-		{
-			name:   "fully-implemented interface",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeedIface)
-				// Make it unbuffered to allow message to
-				// pass through
-				go func() {
-					a := <-testChan
-					if !reflect.DeepEqual(a, o) {
-						t.Errorf("Got = %v, want = %v", a, o)
-					}
-				}()
-				fd.Subscribe(testChan)
-			},
-			obj: testFeed{
-				a: 0,
-				b: "",
-			},
-			expectPanic: false,
-		},
-		{
-			name:   "fully-implemented interface with additional methods",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeedIface)
-				// Make it unbuffered to allow message to
-				// pass through
-				go func() {
-					a := <-testChan
-					if !reflect.DeepEqual(a, o) {
-						t.Errorf("Got = %v, want = %v", a, o)
-					}
-				}()
-				fd.Subscribe(testChan)
-			},
-			obj: testFeed3{
-				a: 0,
-				b: "",
-				c: []byte{'A'},
-				d: []byte{'B'},
-			},
-			expectPanic: false,
-		},
-		{
-			name:   "concrete types implementing the same interface",
-			evFeed: new(Feed),
-			testSetup: func(fd *Feed, t *testing.T, o interface{}) {
-				testChan := make(chan testFeed, 1)
-				// Make it unbuffered to allow message to
-				// pass through
-				go func() {
-					a := <-testChan
-					if !reflect.DeepEqual(a, o) {
-						t.Errorf("Got = %v, want = %v", a, o)
-					}
-				}()
-				fd.Subscribe(testChan)
-			},
-			obj: testFeed3{
-				a: 0,
-				b: "",
-				c: []byte{'A'},
-				d: []byte{'B'},
-			},
-			expectPanic: true,
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			defer func() {
-				if r := recover(); r != nil {
-					if !tt.expectPanic {
-						t.Errorf("panic triggered when unexpected: %v", r)
-					}
-				} else {
-					if tt.expectPanic {
-						t.Error("panic not triggered when expected")
-					}
-				}
-			}()
-			tt.testSetup(tt.evFeed, t, tt.obj)
-			if gotNsent := tt.evFeed.Send(tt.obj); gotNsent != 1 {
-				t.Errorf("Send() = %v, want %v", gotNsent, 1)
-			}
-		})
-	}
-}
-
-// The following objects below are a collection of different
-// struct types to test with.
-type testFeed struct {
-	a uint64
-	b string
-}
-
-func (testFeed) method1() {
-
-}
-
-func (testFeed) method2() {
-
-}
-
-type testFeedWithPointer struct {
-	a *uint64
-	b *string
-}
-
-type testFeed2 struct {
-	a uint64
-	b string
-	c []byte
-}
-
-func (testFeed2) method1() {
-
-}
-
-type testFeed3 struct {
-	a    uint64
-	b    string
-	c, d []byte
-}
-
-func (testFeed3) method1() {
-
-}
-
-func (testFeed3) method2() {
-
-}
-
-func (testFeed3) method3() {
-
-}
-
-type testFeedIface interface {
-	method1()
-	method2()
-}
--- a/async/event/interface.go
+++ b/async/event/interface.go
@@ -0,0 +1,8 @@
+package event
+
+// SubscriberSender is an abstract representation of an *event.Feed
+// to use in describing types that accept or return an *event.Feed.
+type SubscriberSender interface {
+	Subscribe(channel interface{}) Subscription
+	Send(value interface{}) (nsent int)
+}
--- a/async/event/subscription.go
+++ b/async/event/subscription.go
@@ -28,25 +28,6 @@ import (
 // request backoff time.
 const waitQuotient = 10

-// Subscription represents a stream of events. The carrier of the events is typically a
-// channel, but isn't part of the interface.
-//
-// Subscriptions can fail while established. Failures are reported through an error
-// channel. It receives a value if there is an issue with the subscription (e.g. the
-// network connection delivering the events has been closed). Only one value will ever be
-// sent.
-//
-// The error channel is closed when the subscription ends successfully (i.e. when the
-// source of events is closed). It is also closed when Unsubscribe is called.
-//
-// The Unsubscribe method cancels the sending of events. You must call Unsubscribe in all
-// cases to ensure that resources related to the subscription are released. It can be
-// called any number of times.
-type Subscription interface {
-	Err() <-chan error // returns the error channel
-	Unsubscribe()      // cancels sending of events, closing the error channel
-}
-
 // NewSubscription runs a producer function as a subscription in a new goroutine. The
 // channel given to the producer is closed when Unsubscribe is called. If fn returns an
 // error, it is sent on the subscription's error channel.
--- a/beacon-chain/blockchain/BUILD.bazel
+++ b/beacon-chain/blockchain/BUILD.bazel
@@ -25,6 +25,7 @@ go_library(
        "receive_attestation.go",
        "receive_blob.go",
        "receive_block.go",
+        "receive_data_column.go",
        "service.go",
        "tracked_proposer.go",
        "weak_subjectivity_checks.go",
@@ -48,6 +49,7 @@ go_library(
        "//beacon-chain/core/feed/state:go_default_library",
        "//beacon-chain/core/helpers:go_default_library",
        "//beacon-chain/core/light-client:go_default_library",
+        "//beacon-chain/core/peerdas:go_default_library",
        "//beacon-chain/core/signing:go_default_library",
        "//beacon-chain/core/time:go_default_library",
        "//beacon-chain/core/transition:go_default_library",
@@ -84,7 +86,6 @@ go_library(
        "//monitoring/tracing/trace:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/eth/v1:go_default_library",
-        "//proto/eth/v2:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
        "//proto/prysm/v1alpha1/attestation:go_default_library",
        "//runtime/version:go_default_library",
@@ -141,6 +142,7 @@ go_test(
        "//beacon-chain/core/blocks:go_default_library",
        "//beacon-chain/core/feed/state:go_default_library",
        "//beacon-chain/core/helpers:go_default_library",
+        "//beacon-chain/core/light-client:go_default_library",
        "//beacon-chain/core/signing:go_default_library",
        "//beacon-chain/core/transition:go_default_library",
        "//beacon-chain/das:go_default_library",
@@ -157,6 +159,7 @@ go_test(
        "//beacon-chain/operations/slashings:go_default_library",
        "//beacon-chain/operations/voluntaryexits:go_default_library",
        "//beacon-chain/p2p:go_default_library",
+        "//beacon-chain/p2p/testing:go_default_library",
        "//beacon-chain/startup:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//beacon-chain/state/state-native:go_default_library",
--- a/beacon-chain/blockchain/chain_info.go
+++ b/beacon-chain/blockchain/chain_info.go
@@ -12,6 +12,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
+	consensus_blocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/forkchoice"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
@@ -44,7 +45,7 @@ type ForkchoiceFetcher interface {
 	UpdateHead(context.Context, primitives.Slot)
 	HighestReceivedBlockSlot() primitives.Slot
 	ReceivedBlocksLastEpoch() (uint64, error)
-	InsertNode(context.Context, state.BeaconState, [32]byte) error
+	InsertNode(context.Context, state.BeaconState, consensus_blocks.ROBlock) error
 	ForkChoiceDump(context.Context) (*forkchoice.Dump, error)
 	NewSlot(context.Context, primitives.Slot) error
 	ProposerBoost() [32]byte
@@ -242,7 +243,7 @@ func (s *Service) HeadValidatorsIndices(ctx context.Context, epoch primitives.Ep
 	if !s.hasHeadState() {
 		return []primitives.ValidatorIndex{}, nil
 	}
-	return helpers.ActiveValidatorIndices(ctx, s.headState(ctx), epoch)
+	return helpers.ActiveValidatorIndices(ctx, s.headStateReadOnly(ctx), epoch)
 }

 // HeadGenesisValidatorsRoot returns genesis validators root of the head state.
--- a/beacon-chain/blockchain/chain_info_forkchoice.go
+++ b/beacon-chain/blockchain/chain_info_forkchoice.go
@@ -4,6 +4,7 @@ import (
 	"context"

 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	consensus_blocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/forkchoice"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 )
@@ -44,10 +45,10 @@ func (s *Service) ReceivedBlocksLastEpoch() (uint64, error) {
 }

 // InsertNode is a wrapper for node insertion which is self locked
-func (s *Service) InsertNode(ctx context.Context, st state.BeaconState, root [32]byte) error {
+func (s *Service) InsertNode(ctx context.Context, st state.BeaconState, block consensus_blocks.ROBlock) error {
 	s.cfg.ForkChoiceStore.Lock()
 	defer s.cfg.ForkChoiceStore.Unlock()
-	return s.cfg.ForkChoiceStore.InsertNode(ctx, st, root)
+	return s.cfg.ForkChoiceStore.InsertNode(ctx, st, block)
 }

 // ForkChoiceDump returns the corresponding value from forkchoice
--- a/beacon-chain/blockchain/chain_info_test.go
+++ b/beacon-chain/blockchain/chain_info_test.go
@@ -38,7 +38,7 @@ func prepareForkchoiceState(
 	payloadHash [32]byte,
 	justified *ethpb.Checkpoint,
 	finalized *ethpb.Checkpoint,
-) (state.BeaconState, [32]byte, error) {
+) (state.BeaconState, blocks.ROBlock, error) {
 	blockHeader := &ethpb.BeaconBlockHeader{
 		ParentRoot: parentRoot[:],
 	}
@@ -59,7 +59,26 @@ func prepareForkchoiceState(

 	base.BlockRoots[0] = append(base.BlockRoots[0], blockRoot[:]...)
 	st, err := state_native.InitializeFromProtoBellatrix(base)
-	return st, blockRoot, err
+	if err != nil {
+		return nil, blocks.ROBlock{}, err
+	}
+	blk := &ethpb.SignedBeaconBlockBellatrix{
+		Block: &ethpb.BeaconBlockBellatrix{
+			Slot:       slot,
+			ParentRoot: parentRoot[:],
+			Body: &ethpb.BeaconBlockBodyBellatrix{
+				ExecutionPayload: &enginev1.ExecutionPayload{
+					BlockHash: payloadHash[:],
+				},
+			},
+		},
+	}
+	signed, err := blocks.NewSignedBeaconBlock(blk)
+	if err != nil {
+		return nil, blocks.ROBlock{}, err
+	}
+	roblock, err := blocks.NewROBlockWithRoot(signed, blockRoot)
+	return st, roblock, err
 }

 func TestHeadRoot_Nil(t *testing.T) {
@@ -122,9 +141,9 @@ func TestUnrealizedJustifiedBlockHash(t *testing.T) {
 	service := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}}
 	ojc := &ethpb.Checkpoint{Root: []byte{'j'}}
 	ofc := &ethpb.Checkpoint{Root: []byte{'f'}}
-	st, blkRoot, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	st, roblock, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
 	service.cfg.ForkChoiceStore.SetBalancesByRooter(func(_ context.Context, _ [32]byte) ([]uint64, error) { return []uint64{}, nil })
 	require.NoError(t, service.cfg.ForkChoiceStore.UpdateJustifiedCheckpoint(ctx, &forkchoicetypes.Checkpoint{Epoch: 6, Root: [32]byte{'j'}}))

@@ -316,24 +335,24 @@ func TestService_ChainHeads(t *testing.T) {
 	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}}
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	st, blkRoot, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	st, roblock, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 103, [32]byte{'d'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 103, [32]byte{'d'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 104, [32]byte{'e'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 104, [32]byte{'e'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))

 	roots, slots := c.ChainHeads()
 	require.Equal(t, 3, len(roots))
@@ -413,12 +432,12 @@ func TestService_IsOptimistic(t *testing.T) {
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}, head: &head{root: [32]byte{'b'}}}
-	st, blkRoot, err := prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	st, roblock, err := prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))

 	opt, err := c.IsOptimistic(ctx)
 	require.NoError(t, err)
@@ -449,12 +468,12 @@ func TestService_IsOptimisticForRoot(t *testing.T) {
 	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}, head: &head{root: [32]byte{'b'}}}
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	st, blkRoot, err := prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	st, roblock, err := prepareForkchoiceState(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	st, blkRoot, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
+	st, roblock, err = prepareForkchoiceState(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))

 	opt, err := c.IsOptimisticForRoot(ctx, [32]byte{'a'})
 	require.NoError(t, err)
--- a/beacon-chain/blockchain/error.go
+++ b/beacon-chain/blockchain/error.go
@@ -33,6 +33,7 @@ var (
 )

 var errMaxBlobsExceeded = errors.New("Expected commitments in block exceeds MAX_BLOBS_PER_BLOCK")
+var errMaxDataColumnsExceeded = errors.New("Expected data columns for node exceeds NUMBER_OF_COLUMNS")

 // An invalid block is the block that fails state transition based on the core protocol rules.
 // The beacon node shall not be accepting nor building blocks that branch off from an invalid block.
--- a/beacon-chain/blockchain/execution_engine.go
+++ b/beacon-chain/blockchain/execution_engine.go
@@ -2,13 +2,15 @@ package blockchain

 import (
 	"context"
-	"crypto/sha256"
 	"fmt"

 	"github.com/ethereum/go-ethereum/common"
 	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/v5/async/event"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed"
+	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/transition"
@@ -28,8 +30,6 @@ import (
 	"github.com/sirupsen/logrus"
 )

-const blobCommitmentVersionKZG uint8 = 0x01
-
 var defaultLatestValidHash = bytesutil.PadTo([]byte{0xff}, 32)

 // notifyForkchoiceUpdate signals execution engine the fork choice updates. Execution engine should:
@@ -72,6 +72,7 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 	if arg.attributes == nil {
 		arg.attributes = payloadattribute.EmptyWithVersion(headBlk.Version())
 	}
+	go firePayloadAttributesEvent(ctx, s.cfg.StateNotifier.StateFeed(), arg)
 	payloadID, lastValidHash, err := s.cfg.ExecutionEngineCaller.ForkchoiceUpdated(ctx, fcs, arg.attributes)
 	if err != nil {
 		switch {
@@ -170,6 +171,38 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 	return payloadID, nil
 }

+func firePayloadAttributesEvent(ctx context.Context, f event.SubscriberSender, cfg *fcuConfig) {
+	pidx, err := helpers.BeaconProposerIndex(ctx, cfg.headState)
+	if err != nil {
+		log.WithError(err).
+			WithField("head_root", cfg.headRoot[:]).
+			Error("Could not get proposer index for PayloadAttributes event")
+		return
+	}
+	evd := payloadattribute.EventData{
+		ProposerIndex:   pidx,
+		ProposalSlot:    cfg.headState.Slot(),
+		ParentBlockRoot: cfg.headRoot[:],
+		Attributer:      cfg.attributes,
+		HeadRoot:        cfg.headRoot,
+		HeadState:       cfg.headState,
+		HeadBlock:       cfg.headBlock,
+	}
+	if cfg.headBlock != nil && !cfg.headBlock.IsNil() {
+		headPayload, err := cfg.headBlock.Block().Body().Execution()
+		if err != nil {
+			log.WithError(err).Error("Could not get execution payload for head block")
+			return
+		}
+		evd.ParentBlockHash = headPayload.BlockHash()
+		evd.ParentBlockNumber = headPayload.BlockNumber()
+	}
+	f.Send(&feed.Event{
+		Type: statefeed.PayloadAttributes,
+		Data: evd,
+	})
+}
+
 // getPayloadHash returns the payload hash given the block root.
 // if the block is before bellatrix fork epoch, it returns the zero hash.
 func (s *Service) getPayloadHash(ctx context.Context, root []byte) ([32]byte, error) {
@@ -219,17 +252,25 @@ func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion int,
 	}

 	var lastValidHash []byte
+	var parentRoot *common.Hash
+	var versionedHashes []common.Hash
+	var requests *enginev1.ExecutionRequests
 	if blk.Version() >= version.Deneb {
-		var versionedHashes []common.Hash
 		versionedHashes, err = kzgCommitmentsToVersionedHashes(blk.Block().Body())
 		if err != nil {
 			return false, errors.Wrap(err, "could not get versioned hashes to feed the engine")
 		}
-		pr := common.Hash(blk.Block().ParentRoot())
-		lastValidHash, err = s.cfg.ExecutionEngineCaller.NewPayload(ctx, payload, versionedHashes, &pr)
-	} else {
-		lastValidHash, err = s.cfg.ExecutionEngineCaller.NewPayload(ctx, payload, []common.Hash{}, &common.Hash{} /*empty version hashes and root before Deneb*/)
+		prh := common.Hash(blk.Block().ParentRoot())
+		parentRoot = &prh
 	}
+	if blk.Version() >= version.Electra {
+		requests, err = blk.Block().Body().ExecutionRequests()
+		if err != nil {
+			return false, errors.Wrap(err, "could not get execution requests")
+		}
+	}
+	lastValidHash, err = s.cfg.ExecutionEngineCaller.NewPayload(ctx, payload, versionedHashes, parentRoot, requests)
+
 	switch {
 	case err == nil:
 		newPayloadValidNodeCount.Inc()
@@ -321,15 +362,16 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 		return emptyAttri
 	}

-	var attr payloadattribute.Attributer
-	switch st.Version() {
-	case version.Deneb, version.Electra:
+	v := st.Version()
+
+	if v >= version.Deneb {
 		withdrawals, _, err := st.ExpectedWithdrawals()
 		if err != nil {
 			log.WithError(err).Error("Could not get expected withdrawals to get payload attribute")
 			return emptyAttri
 		}
-		attr, err = payloadattribute.New(&enginev1.PayloadAttributesV3{
+
+		attr, err := payloadattribute.New(&enginev1.PayloadAttributesV3{
 			Timestamp:             uint64(t.Unix()),
 			PrevRandao:            prevRando,
 			SuggestedFeeRecipient: val.FeeRecipient[:],
@@ -340,13 +382,18 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 			log.WithError(err).Error("Could not get payload attribute")
 			return emptyAttri
 		}
-	case version.Capella:
+
+		return attr
+	}
+
+	if v >= version.Capella {
 		withdrawals, _, err := st.ExpectedWithdrawals()
 		if err != nil {
 			log.WithError(err).Error("Could not get expected withdrawals to get payload attribute")
 			return emptyAttri
 		}
-		attr, err = payloadattribute.New(&enginev1.PayloadAttributesV2{
+
+		attr, err := payloadattribute.New(&enginev1.PayloadAttributesV2{
 			Timestamp:             uint64(t.Unix()),
 			PrevRandao:            prevRando,
 			SuggestedFeeRecipient: val.FeeRecipient[:],
@@ -356,8 +403,12 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 			log.WithError(err).Error("Could not get payload attribute")
 			return emptyAttri
 		}
-	case version.Bellatrix:
-		attr, err = payloadattribute.New(&enginev1.PayloadAttributes{
+
+		return attr
+	}
+
+	if v >= version.Bellatrix {
+		attr, err := payloadattribute.New(&enginev1.PayloadAttributes{
 			Timestamp:             uint64(t.Unix()),
 			PrevRandao:            prevRando,
 			SuggestedFeeRecipient: val.FeeRecipient[:],
@@ -366,12 +417,12 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 			log.WithError(err).Error("Could not get payload attribute")
 			return emptyAttri
 		}
-	default:
-		log.WithField("version", st.Version()).Error("Could not get payload attribute due to unknown state version")
-		return emptyAttri
+
+		return attr
 	}

-	return attr
+	log.WithField("version", version.String(st.Version())).Error("Could not get payload attribute due to unknown state version")
+	return emptyAttri
 }

 // removeInvalidBlockAndState removes the invalid block, blob and its corresponding state from the cache and DB.
@@ -402,13 +453,7 @@ func kzgCommitmentsToVersionedHashes(body interfaces.ReadOnlyBeaconBlockBody) ([

 	versionedHashes := make([]common.Hash, len(commitments))
 	for i, commitment := range commitments {
-		versionedHashes[i] = ConvertKzgCommitmentToVersionedHash(commitment)
+		versionedHashes[i] = primitives.ConvertKzgCommitmentToVersionedHash(commitment)
 	}
 	return versionedHashes, nil
 }
-
-func ConvertKzgCommitmentToVersionedHash(commitment []byte) common.Hash {
-	versionedHash := sha256.Sum256(commitment)
-	versionedHash[0] = blobCommitmentVersionKZG
-	return versionedHash
-}
--- a/beacon-chain/blockchain/execution_engine_test.go
+++ b/beacon-chain/blockchain/execution_engine_test.go
@@ -1135,9 +1135,14 @@ func TestComputePayloadAttribute(t *testing.T) {
 	// Cache hit, advance state, no fee recipient
 	slot := primitives.Slot(1)
 	service.cfg.PayloadIDCache.Set(slot, [32]byte{}, [8]byte{})
+	blk := util.NewBeaconBlockBellatrix()
+	signed, err := consensusblocks.NewSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	roblock, err := consensusblocks.NewROBlockWithRoot(signed, [32]byte{'a'})
+	require.NoError(t, err)
 	cfg := &postBlockProcessConfig{
-		ctx:       ctx,
-		blockRoot: [32]byte{'a'},
+		ctx:     ctx,
+		roblock: roblock,
 	}
 	fcu := &fcuConfig{
 		headState:     st,
--- a/beacon-chain/blockchain/head.go
+++ b/beacon-chain/blockchain/head.go
@@ -11,6 +11,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/v5/config/features"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
@@ -404,13 +405,19 @@ func (s *Service) saveOrphanedOperations(ctx context.Context, orphanedRoot [32]b
 			if a.GetData().Slot+params.BeaconConfig().SlotsPerEpoch < s.CurrentSlot() {
 				continue
 			}
-			if helpers.IsAggregated(a) {
-				if err := s.cfg.AttPool.SaveAggregatedAttestation(a); err != nil {
+			if features.Get().EnableExperimentalAttestationPool {
+				if err = s.cfg.AttestationCache.Add(a); err != nil {
 					return err
 				}
 			} else {
-				if err := s.cfg.AttPool.SaveUnaggregatedAttestation(a); err != nil {
-					return err
+				if a.IsAggregated() {
+					if err = s.cfg.AttPool.SaveAggregatedAttestation(a); err != nil {
+						return err
+					}
+				} else {
+					if err = s.cfg.AttPool.SaveUnaggregatedAttestation(a); err != nil {
+						return err
+					}
 				}
 			}
 			saveOrphanedAttCount.Inc()
--- a/beacon-chain/blockchain/kzg/BUILD.bazel
+++ b/beacon-chain/blockchain/kzg/BUILD.bazel
@@ -3,6 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
    name = "go_default_library",
    srcs = [
+        "kzg.go",
        "trusted_setup.go",
        "validation.go",
    ],
@@ -12,6 +13,9 @@ go_library(
    deps = [
        "//consensus-types/blocks:go_default_library",
        "@com_github_crate_crypto_go_kzg_4844//:go_default_library",
+        "@com_github_ethereum_c_kzg_4844//bindings/go:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_ethereum_go_ethereum//crypto/kzg4844:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
    ],
 )
@@ -26,8 +30,7 @@ go_test(
    deps = [
        "//consensus-types/blocks:go_default_library",
        "//testing/require:go_default_library",
-        "@com_github_consensys_gnark_crypto//ecc/bls12-381/fr:go_default_library",
+        "//testing/util:go_default_library",
        "@com_github_crate_crypto_go_kzg_4844//:go_default_library",
-        "@com_github_sirupsen_logrus//:go_default_library",
    ],
 )
--- a/beacon-chain/blockchain/kzg/kzg.go
+++ b/beacon-chain/blockchain/kzg/kzg.go
@@ -0,0 +1,111 @@
+package kzg
+
+import (
+	"errors"
+
+	ckzg4844 "github.com/ethereum/c-kzg-4844/v2/bindings/go"
+	"github.com/ethereum/go-ethereum/crypto/kzg4844"
+)
+
+// BytesPerBlob is the number of bytes in a single blob.
+const BytesPerBlob = ckzg4844.BytesPerBlob
+
+// Blob represents a serialized chunk of data.
+type Blob [BytesPerBlob]byte
+
+// BytesPerCell is the number of bytes in a single cell.
+const BytesPerCell = ckzg4844.BytesPerCell
+
+// Cell represents a chunk of an encoded Blob.
+type Cell [BytesPerCell]byte
+
+// Commitment represent a KZG commitment to a Blob.
+type Commitment [48]byte
+
+// Proof represents a KZG proof that attests to the validity of a Blob or parts of it.
+type Proof [48]byte
+
+// Bytes48 is a 48-byte array.
+type Bytes48 = ckzg4844.Bytes48
+
+// Bytes32 is a 32-byte array.
+type Bytes32 = ckzg4844.Bytes32
+
+// CellsAndProofs represents the Cells and Proofs corresponding to
+// a single blob.
+type CellsAndProofs struct {
+	Cells  []Cell
+	Proofs []Proof
+}
+
+func BlobToKZGCommitment(blob *Blob) (Commitment, error) {
+	kzgBlob := kzg4844.Blob(*blob)
+	comm, err := kzg4844.BlobToCommitment(&kzgBlob)
+	if err != nil {
+		return Commitment{}, err
+	}
+	return Commitment(comm), nil
+}
+
+func ComputeBlobKZGProof(blob *Blob, commitment Commitment) (Proof, error) {
+	kzgBlob := kzg4844.Blob(*blob)
+	proof, err := kzg4844.ComputeBlobProof(&kzgBlob, kzg4844.Commitment(commitment))
+	if err != nil {
+		return [48]byte{}, err
+	}
+	return Proof(proof), nil
+}
+
+func ComputeCellsAndKZGProofs(blob *Blob) (CellsAndProofs, error) {
+	ckzgBlob := (*ckzg4844.Blob)(blob)
+	ckzgCells, ckzgProofs, err := ckzg4844.ComputeCellsAndKZGProofs(ckzgBlob)
+	if err != nil {
+		return CellsAndProofs{}, err
+	}
+
+	return makeCellsAndProofs(ckzgCells[:], ckzgProofs[:])
+}
+
+func VerifyCellKZGProofBatch(commitmentsBytes []Bytes48, cellIndices []uint64, cells []Cell, proofsBytes []Bytes48) (bool, error) {
+	// Convert `Cell` type to `ckzg4844.Cell`
+	ckzgCells := make([]ckzg4844.Cell, len(cells))
+	for i := range cells {
+		ckzgCells[i] = ckzg4844.Cell(cells[i])
+	}
+
+	return ckzg4844.VerifyCellKZGProofBatch(commitmentsBytes, cellIndices, ckzgCells, proofsBytes)
+}
+
+func RecoverCellsAndKZGProofs(cellIndices []uint64, partialCells []Cell) (CellsAndProofs, error) {
+	// Convert `Cell` type to `ckzg4844.Cell`
+	ckzgPartialCells := make([]ckzg4844.Cell, len(partialCells))
+	for i := range partialCells {
+		ckzgPartialCells[i] = ckzg4844.Cell(partialCells[i])
+	}
+
+	ckzgCells, ckzgProofs, err := ckzg4844.RecoverCellsAndKZGProofs(cellIndices, ckzgPartialCells)
+	if err != nil {
+		return CellsAndProofs{}, err
+	}
+
+	return makeCellsAndProofs(ckzgCells[:], ckzgProofs[:])
+}
+
+// Convert cells/proofs to the CellsAndProofs type defined in this package.
+func makeCellsAndProofs(ckzgCells []ckzg4844.Cell, ckzgProofs []ckzg4844.KZGProof) (CellsAndProofs, error) {
+	if len(ckzgCells) != len(ckzgProofs) {
+		return CellsAndProofs{}, errors.New("different number of cells/proofs")
+	}
+
+	var cells []Cell
+	var proofs []Proof
+	for i := range ckzgCells {
+		cells = append(cells, Cell(ckzgCells[i]))
+		proofs = append(proofs, Proof(ckzgProofs[i]))
+	}
+
+	return CellsAndProofs{
+		Cells:  cells,
+		Proofs: proofs,
+	}, nil
+}
--- a/beacon-chain/blockchain/kzg/trusted_setup.go
+++ b/beacon-chain/blockchain/kzg/trusted_setup.go
@@ -5,6 +5,8 @@ import (
 	"encoding/json"

 	GoKZG "github.com/crate-crypto/go-kzg-4844"
+	CKZG "github.com/ethereum/c-kzg-4844/v2/bindings/go"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
 )

@@ -12,17 +14,53 @@ var (
 	//go:embed trusted_setup.json
 	embeddedTrustedSetup []byte // 1.2Mb
 	kzgContext           *GoKZG.Context
+	kzgLoaded            bool
 )

+type TrustedSetup struct {
+	G1Monomial [GoKZG.ScalarsPerBlob]GoKZG.G1CompressedHexStr `json:"g1_monomial"`
+	G1Lagrange [GoKZG.ScalarsPerBlob]GoKZG.G1CompressedHexStr `json:"g1_lagrange"`
+	G2Monomial [65]GoKZG.G2CompressedHexStr                   `json:"g2_monomial"`
+}
+
 func Start() error {
-	parsedSetup := GoKZG.JSONTrustedSetup{}
-	err := json.Unmarshal(embeddedTrustedSetup, &parsedSetup)
+	trustedSetup := &TrustedSetup{}
+	err := json.Unmarshal(embeddedTrustedSetup, trustedSetup)
 	if err != nil {
 		return errors.Wrap(err, "could not parse trusted setup JSON")
 	}
-	kzgContext, err = GoKZG.NewContext4096(&parsedSetup)
+	kzgContext, err = GoKZG.NewContext4096(&GoKZG.JSONTrustedSetup{
+		SetupG2:         trustedSetup.G2Monomial[:],
+		SetupG1Lagrange: trustedSetup.G1Lagrange})
 	if err != nil {
 		return errors.Wrap(err, "could not initialize go-kzg context")
 	}
+
+	// Length of a G1 point, converted from hex to binary.
+	g1MonomialBytes := make([]byte, len(trustedSetup.G1Monomial)*(len(trustedSetup.G1Monomial[0])-2)/2)
+	for i, g1 := range &trustedSetup.G1Monomial {
+		copy(g1MonomialBytes[i*(len(g1)-2)/2:], hexutil.MustDecode(g1))
+	}
+	// Length of a G1 point, converted from hex to binary.
+	g1LagrangeBytes := make([]byte, len(trustedSetup.G1Lagrange)*(len(trustedSetup.G1Lagrange[0])-2)/2)
+	for i, g1 := range &trustedSetup.G1Lagrange {
+		copy(g1LagrangeBytes[i*(len(g1)-2)/2:], hexutil.MustDecode(g1))
+	}
+	// Length of a G2 point, converted from hex to binary.
+	g2MonomialBytes := make([]byte, len(trustedSetup.G2Monomial)*(len(trustedSetup.G2Monomial[0])-2)/2)
+	for i, g2 := range &trustedSetup.G2Monomial {
+		copy(g2MonomialBytes[i*(len(g2)-2)/2:], hexutil.MustDecode(g2))
+	}
+	if !kzgLoaded {
+		// TODO: Provide a configuration option for this.
+		var precompute uint = 8
+
+		// Free the current trusted setup before running this method. CKZG
+		// panics if the same setup is run multiple times.
+		if err = CKZG.LoadTrustedSetup(g1MonomialBytes, g1LagrangeBytes, g2MonomialBytes, precompute); err != nil {
+			panic(err)
+		}
+	}
+	kzgLoaded = true
 	return nil
 }
--- a/beacon-chain/blockchain/kzg/trusted_setup.json
+++ b/beacon-chain/blockchain/kzg/trusted_setup.json
--- a/beacon-chain/blockchain/kzg/validation.go
+++ b/beacon-chain/blockchain/kzg/validation.go
@@ -20,16 +20,17 @@ func Verify(sidecars ...blocks.ROBlob) error {
 	cmts := make([]GoKZG.KZGCommitment, len(sidecars))
 	proofs := make([]GoKZG.KZGProof, len(sidecars))
 	for i, sidecar := range sidecars {
-		blobs[i] = bytesToBlob(sidecar.Blob)
+		blobs[i] = *bytesToBlob(sidecar.Blob)
 		cmts[i] = bytesToCommitment(sidecar.KzgCommitment)
 		proofs[i] = bytesToKZGProof(sidecar.KzgProof)
 	}
 	return kzgContext.VerifyBlobKZGProofBatch(blobs, cmts, proofs)
 }

-func bytesToBlob(blob []byte) (ret GoKZG.Blob) {
+func bytesToBlob(blob []byte) *GoKZG.Blob {
+	var ret GoKZG.Blob
 	copy(ret[:], blob)
-	return
+	return &ret
 }

 func bytesToCommitment(commitment []byte) (ret GoKZG.KZGCommitment) {
--- a/beacon-chain/blockchain/kzg/validation_test.go
+++ b/beacon-chain/blockchain/kzg/validation_test.go
@@ -1,57 +1,20 @@
 package kzg

 import (
-	"bytes"
-	"crypto/sha256"
-	"encoding/binary"
 	"testing"

-	"github.com/consensys/gnark-crypto/ecc/bls12-381/fr"
 	GoKZG "github.com/crate-crypto/go-kzg-4844"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/sirupsen/logrus"
+	"github.com/prysmaticlabs/prysm/v5/testing/util"
 )

-func deterministicRandomness(seed int64) [32]byte {
-	// Converts an int64 to a byte slice
-	buf := new(bytes.Buffer)
-	err := binary.Write(buf, binary.BigEndian, seed)
-	if err != nil {
-		logrus.WithError(err).Error("Failed to write int64 to bytes buffer")
-		return [32]byte{}
-	}
-	bytes := buf.Bytes()
-
-	return sha256.Sum256(bytes)
-}
-
-// Returns a serialized random field element in big-endian
-func GetRandFieldElement(seed int64) [32]byte {
-	bytes := deterministicRandomness(seed)
-	var r fr.Element
-	r.SetBytes(bytes[:])
-
-	return GoKZG.SerializeScalar(r)
-}
-
-// Returns a random blob using the passed seed as entropy
-func GetRandBlob(seed int64) GoKZG.Blob {
-	var blob GoKZG.Blob
-	bytesPerBlob := GoKZG.ScalarsPerBlob * GoKZG.SerializedScalarSize
-	for i := 0; i < bytesPerBlob; i += GoKZG.SerializedScalarSize {
-		fieldElementBytes := GetRandFieldElement(seed + int64(i))
-		copy(blob[i:i+GoKZG.SerializedScalarSize], fieldElementBytes[:])
-	}
-	return blob
-}
-
 func GenerateCommitmentAndProof(blob GoKZG.Blob) (GoKZG.KZGCommitment, GoKZG.KZGProof, error) {
-	commitment, err := kzgContext.BlobToKZGCommitment(blob, 0)
+	commitment, err := kzgContext.BlobToKZGCommitment(&blob, 0)
 	if err != nil {
 		return GoKZG.KZGCommitment{}, GoKZG.KZGProof{}, err
 	}
-	proof, err := kzgContext.ComputeBlobKZGProof(blob, commitment, 0)
+	proof, err := kzgContext.ComputeBlobKZGProof(&blob, commitment, 0)
 	if err != nil {
 		return GoKZG.KZGCommitment{}, GoKZG.KZGProof{}, err
 	}
@@ -68,13 +31,13 @@ func TestBytesToAny(t *testing.T) {
 	blob := GoKZG.Blob{0x01, 0x02}
 	commitment := GoKZG.KZGCommitment{0x01, 0x02}
 	proof := GoKZG.KZGProof{0x01, 0x02}
-	require.DeepEqual(t, blob, bytesToBlob(bytes))
+	require.DeepEqual(t, blob, *bytesToBlob(bytes))
 	require.DeepEqual(t, commitment, bytesToCommitment(bytes))
 	require.DeepEqual(t, proof, bytesToKZGProof(bytes))
 }

 func TestGenerateCommitmentAndProof(t *testing.T) {
-	blob := GetRandBlob(123)
+	blob := util.GetRandBlob(123)
 	commitment, proof, err := GenerateCommitmentAndProof(blob)
 	require.NoError(t, err)
 	expectedCommitment := GoKZG.KZGCommitment{180, 218, 156, 194, 59, 20, 10, 189, 186, 254, 132, 93, 7, 127, 104, 172, 238, 240, 237, 70, 83, 89, 1, 152, 99, 0, 165, 65, 143, 62, 20, 215, 230, 14, 205, 95, 28, 245, 54, 25, 160, 16, 178, 31, 232, 207, 38, 85}
--- a/beacon-chain/blockchain/options.go
+++ b/beacon-chain/blockchain/options.go
@@ -85,6 +85,14 @@ func WithTrackedValidatorsCache(c *cache.TrackedValidatorsCache) Option {
 	}
 }

+// WithAttestationCache for attestation lifecycle after chain inclusion.
+func WithAttestationCache(c *cache.AttestationCache) Option {
+	return func(s *Service) error {
+		s.cfg.AttestationCache = c
+		return nil
+	}
+}
+
 // WithAttestationPool for attestation lifecycle after chain inclusion.
 func WithAttestationPool(p attestations.Pool) Option {
 	return func(s *Service) error {
@@ -118,9 +126,9 @@ func WithBLSToExecPool(p blstoexec.PoolManager) Option {
 }

 // WithP2PBroadcaster to broadcast messages after appropriate processing.
-func WithP2PBroadcaster(p p2p.Broadcaster) Option {
+func WithP2PBroadcaster(p p2p.Acceser) Option {
 	return func(s *Service) error {
-		s.cfg.P2p = p
+		s.cfg.P2P = p
 		return nil
 	}
 }
--- a/beacon-chain/blockchain/process_attestation_test.go
+++ b/beacon-chain/blockchain/process_attestation_test.go
@@ -32,18 +32,18 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 	util.SaveBlock(t, ctx, beaconDB, blkWithoutState)

 	cp := &ethpb.Checkpoint{}
-	st, blkRoot, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, cp, cp)
+	st, roblock, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, cp, cp)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))

 	blkWithStateBadAtt := util.NewBeaconBlock()
 	blkWithStateBadAtt.Block.Slot = 1
 	r, err := blkWithStateBadAtt.Block.HashTreeRoot()
 	require.NoError(t, err)
 	cp = &ethpb.Checkpoint{Root: r[:]}
-	st, blkRoot, err = prepareForkchoiceState(ctx, blkWithStateBadAtt.Block.Slot, r, [32]byte{}, params.BeaconConfig().ZeroHash, cp, cp)
+	st, roblock, err = prepareForkchoiceState(ctx, blkWithStateBadAtt.Block.Slot, r, [32]byte{}, params.BeaconConfig().ZeroHash, cp, cp)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
 	util.SaveBlock(t, ctx, beaconDB, blkWithStateBadAtt)
 	BlkWithStateBadAttRoot, err := blkWithStateBadAtt.Block.HashTreeRoot()
 	require.NoError(t, err)
@@ -92,12 +92,12 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 		{
 			name:      "process nil attestation",
 			a:         nil,
-			wantedErr: "attestation can't be nil",
+			wantedErr: "attestation is nil",
 		},
 		{
 			name:      "process nil field (a.Data) in attestation",
 			a:         &ethpb.Attestation{},
-			wantedErr: "attestation's data can't be nil",
+			wantedErr: "attestation is nil",
 		},
 		{
 			name: "process nil field (a.Target) in attestation",
@@ -139,9 +139,9 @@ func TestStore_OnAttestation_Ok_DoublyLinkedTree(t *testing.T) {
 		require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
 		ojc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
 		ofc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
-		state, blkRoot, err := prepareForkchoiceState(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
+		state, roblock, err := prepareForkchoiceState(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
 		require.NoError(t, err)
-		require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
+		require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, roblock))
 		require.NoError(t, service.OnAttestation(ctx, att[0], 0))
 	}

@@ -318,10 +318,9 @@ func TestStore_UpdateCheckpointState(t *testing.T) {
 	require.NoError(t, err)
 	checkpoint := &ethpb.Checkpoint{Epoch: epoch, Root: r1[:]}
 	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, baseState, bytesutil.ToBytes32(checkpoint.Root)))
-	st, blkRoot, err := prepareForkchoiceState(ctx, blk.Block.Slot, r1, [32]byte{}, params.BeaconConfig().ZeroHash, checkpoint, checkpoint)
+	st, roblock, err := prepareForkchoiceState(ctx, blk.Block.Slot, r1, [32]byte{}, params.BeaconConfig().ZeroHash, checkpoint, checkpoint)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, r1))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
 	returned, err := service.getAttPreState(ctx, checkpoint)
 	require.NoError(t, err)
 	assert.Equal(t, params.BeaconConfig().SlotsPerEpoch.Mul(uint64(checkpoint.Epoch)), returned.Slot(), "Incorrectly returned base state")
@@ -337,10 +336,9 @@ func TestStore_UpdateCheckpointState(t *testing.T) {
 	require.NoError(t, err)
 	newCheckpoint := &ethpb.Checkpoint{Epoch: epoch, Root: r2[:]}
 	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, baseState, bytesutil.ToBytes32(newCheckpoint.Root)))
-	st, blkRoot, err = prepareForkchoiceState(ctx, blk.Block.Slot, r2, r1, params.BeaconConfig().ZeroHash, newCheckpoint, newCheckpoint)
+	st, roblock, err = prepareForkchoiceState(ctx, blk.Block.Slot, r2, r1, params.BeaconConfig().ZeroHash, newCheckpoint, newCheckpoint)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, r2))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, roblock))
 	returned, err = service.getAttPreState(ctx, newCheckpoint)
 	require.NoError(t, err)
 	s, err := slots.EpochStart(newCheckpoint.Epoch)
--- a/beacon-chain/blockchain/process_block.go
+++ b/beacon-chain/blockchain/process_block.go
@@ -3,13 +3,13 @@ package blockchain
 import (
 	"context"
 	"fmt"
+	"slices"
 	"time"

 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed"
-	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/peerdas"
 	coreTime "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/transition"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/das"
@@ -17,7 +17,6 @@ import (
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v5/config/features"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
@@ -46,8 +45,7 @@ var initialSyncBlockCacheSize = uint64(2 * params.BeaconConfig().SlotsPerEpoch)
 // process the beacon block after validating the state transition function
 type postBlockProcessConfig struct {
 	ctx            context.Context
-	signed         interfaces.ReadOnlySignedBeaconBlock
-	blockRoot      [32]byte
+	roblock        consensusblocks.ROBlock
 	headRoot       [32]byte
 	postState      state.BeaconState
 	isValidPayload bool
@@ -61,7 +59,7 @@ func (s *Service) postBlockProcess(cfg *postBlockProcessConfig) error {
 	ctx, span := trace.StartSpan(cfg.ctx, "blockChain.onBlock")
 	defer span.End()
 	cfg.ctx = ctx
-	if err := consensusblocks.BeaconBlockIsNil(cfg.signed); err != nil {
+	if err := consensusblocks.BeaconBlockIsNil(cfg.roblock); err != nil {
 		return invalidBlock{error: err}
 	}
 	startTime := time.Now()
@@ -70,22 +68,29 @@ func (s *Service) postBlockProcess(cfg *postBlockProcessConfig) error {
 	if s.inRegularSync() {
 		defer s.handleSecondFCUCall(cfg, fcuArgs)
 	}
-	defer s.sendLightClientFeeds(cfg)
+	if features.Get().EnableLightClient && slots.ToEpoch(s.CurrentSlot()) >= params.BeaconConfig().AltairForkEpoch {
+		defer s.processLightClientUpdates(cfg)
+		defer s.saveLightClientUpdate(cfg)
+		defer s.saveLightClientBootstrap(cfg)
+	}
 	defer s.sendStateFeedOnBlock(cfg)
 	defer reportProcessingTime(startTime)
-	defer reportAttestationInclusion(cfg.signed.Block())
+	defer reportAttestationInclusion(cfg.roblock.Block())

-	err := s.cfg.ForkChoiceStore.InsertNode(ctx, cfg.postState, cfg.blockRoot)
+	err := s.cfg.ForkChoiceStore.InsertNode(ctx, cfg.postState, cfg.roblock)
 	if err != nil {
-		return errors.Wrapf(err, "could not insert block %d to fork choice store", cfg.signed.Block().Slot())
+		// Do not use parent context in the event it deadlined
+		ctx = trace.NewContext(context.Background(), span)
+		s.rollbackBlock(ctx, cfg.roblock.Root())
+		return errors.Wrapf(err, "could not insert block %d to fork choice store", cfg.roblock.Block().Slot())
 	}
-	if err := s.handleBlockAttestations(ctx, cfg.signed.Block(), cfg.postState); err != nil {
+	if err := s.handleBlockAttestations(ctx, cfg.roblock.Block(), cfg.postState); err != nil {
 		return errors.Wrap(err, "could not handle block's attestations")
 	}

-	s.InsertSlashingsToForkChoiceStore(ctx, cfg.signed.Block().Body().AttesterSlashings())
+	s.InsertSlashingsToForkChoiceStore(ctx, cfg.roblock.Block().Body().AttesterSlashings())
 	if cfg.isValidPayload {
-		if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, cfg.blockRoot); err != nil {
+		if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, cfg.roblock.Root()); err != nil {
 			return errors.Wrap(err, "could not set optimistic block to valid")
 		}
 	}
@@ -95,8 +100,8 @@ func (s *Service) postBlockProcess(cfg *postBlockProcessConfig) error {
 		log.WithError(err).Warn("Could not update head")
 	}
 	newBlockHeadElapsedTime.Observe(float64(time.Since(start).Milliseconds()))
-	if cfg.headRoot != cfg.blockRoot {
-		s.logNonCanonicalBlockReceived(cfg.blockRoot, cfg.headRoot)
+	if cfg.headRoot != cfg.roblock.Root() {
+		s.logNonCanonicalBlockReceived(cfg.roblock.Root(), cfg.headRoot)
 		return nil
 	}
 	if err := s.getFCUArgs(cfg, fcuArgs); err != nil {
@@ -154,7 +159,7 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 	}

 	// Fill in missing blocks
-	if err := s.fillInForkChoiceMissingBlocks(ctx, blks[0].Block(), preState.CurrentJustifiedCheckpoint(), preState.FinalizedCheckpoint()); err != nil {
+	if err := s.fillInForkChoiceMissingBlocks(ctx, blks[0], preState.CurrentJustifiedCheckpoint(), preState.FinalizedCheckpoint()); err != nil {
 		return errors.Wrap(err, "could not fill in missing blocks to forkchoice")
 	}

@@ -231,10 +236,12 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 				return err
 			}
 		}
-		if err := avs.IsDataAvailable(ctx, s.CurrentSlot(), b); err != nil {
+
+		nodeID := s.cfg.P2P.NodeID()
+		if err := avs.IsDataAvailable(ctx, nodeID, s.CurrentSlot(), b); err != nil {
 			return errors.Wrapf(err, "could not validate blob data availability at slot %d", b.Block().Slot())
 		}
-		args := &forkchoicetypes.BlockAndCheckpoints{Block: b.Block(),
+		args := &forkchoicetypes.BlockAndCheckpoints{Block: b,
 			JustifiedCheckpoint: jCheckpoints[i],
 			FinalizedCheckpoint: fCheckpoints[i]}
 		pendingNodes[len(blks)-i-1] = args
@@ -279,7 +286,7 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 		return errors.Wrap(err, "could not insert batch to forkchoice")
 	}
 	// Insert the last block to forkchoice
-	if err := s.cfg.ForkChoiceStore.InsertNode(ctx, preState, lastBR); err != nil {
+	if err := s.cfg.ForkChoiceStore.InsertNode(ctx, preState, lastB); err != nil {
 		return errors.Wrap(err, "could not insert last block in batch to forkchoice")
 	}
 	// Set their optimistic status
@@ -376,7 +383,11 @@ func (s *Service) handleBlockAttestations(ctx context.Context, blk interfaces.Re
 		r := bytesutil.ToBytes32(a.GetData().BeaconBlockRoot)
 		if s.cfg.ForkChoiceStore.HasNode(r) {
 			s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indices, r, a.GetData().Target.Epoch)
-		} else if err := s.cfg.AttPool.SaveBlockAttestation(a); err != nil {
+		} else if features.Get().EnableExperimentalAttestationPool {
+			if err = s.cfg.AttestationCache.Add(a); err != nil {
+				return err
+			}
+		} else if err = s.cfg.AttPool.SaveBlockAttestation(a); err != nil {
 			return err
 		}
 	}
@@ -404,6 +415,9 @@ func (s *Service) savePostStateInfo(ctx context.Context, r [32]byte, b interface
 		return errors.Wrapf(err, "could not save block from slot %d", b.Block().Slot())
 	}
 	if err := s.cfg.StateGen.SaveState(ctx, r, st); err != nil {
+		// Do not use parent context in the event it deadlined
+		ctx = trace.NewContext(context.Background(), span)
+		s.rollbackBlock(ctx, r)
 		return errors.Wrap(err, "could not save state")
 	}
 	return nil
@@ -413,7 +427,11 @@ func (s *Service) savePostStateInfo(ctx context.Context, r [32]byte, b interface
 func (s *Service) pruneAttsFromPool(headBlock interfaces.ReadOnlySignedBeaconBlock) error {
 	atts := headBlock.Block().Body().Attestations()
 	for _, att := range atts {
-		if helpers.IsAggregated(att) {
+		if features.Get().EnableExperimentalAttestationPool {
+			if err := s.cfg.AttestationCache.DeleteCovered(att); err != nil {
+				return errors.Wrap(err, "could not delete attestation")
+			}
+		} else if att.IsAggregated() {
 			if err := s.cfg.AttPool.DeleteAggregatedAttestation(att); err != nil {
 				return err
 			}
@@ -490,16 +508,17 @@ func (s *Service) runLateBlockTasks() {
 // It returns a map where each key represents a missing BlobSidecar index.
 // An empty map means we have all indices; a non-empty map can be used to compare incoming
 // BlobSidecars against the set of known missing sidecars.
-func missingIndices(bs *filesystem.BlobStorage, root [32]byte, expected [][]byte) (map[uint64]struct{}, error) {
+func missingIndices(bs *filesystem.BlobStorage, root [32]byte, expected [][]byte, slot primitives.Slot) (map[uint64]struct{}, error) {
+	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
 	if len(expected) == 0 {
 		return nil, nil
 	}
-	if len(expected) > fieldparams.MaxBlobsPerBlock {
+	if len(expected) > maxBlobsPerBlock {
 		return nil, errMaxBlobsExceeded
 	}
-	indices, err := bs.Indices(root)
+	indices, err := bs.Indices(root, slot)
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "indices")
 	}
 	missing := make(map[uint64]struct{}, len(expected))
 	for i := range expected {
@@ -513,12 +532,40 @@ func missingIndices(bs *filesystem.BlobStorage, root [32]byte, expected [][]byte
 	return missing, nil
 }

+func missingDataColumns(bs *filesystem.BlobStorage, root [32]byte, expected map[uint64]bool) (map[uint64]bool, error) {
+	if len(expected) == 0 {
+		return nil, nil
+	}
+
+	if len(expected) > int(params.BeaconConfig().NumberOfColumns) {
+		return nil, errMaxDataColumnsExceeded
+	}
+
+	indices, err := bs.ColumnIndices(root)
+	if err != nil {
+		return nil, err
+	}
+
+	missing := make(map[uint64]bool, len(expected))
+	for col := range expected {
+		if !indices[col] {
+			missing[col] = true
+		}
+	}
+
+	return missing, nil
+}
+
 // isDataAvailable blocks until all BlobSidecars committed to in the block are available,
 // or an error or context cancellation occurs. A nil result means that the data availability check is successful.
 // The function will first check the database to see if all sidecars have been persisted. If any
 // sidecars are missing, it will then read from the blobNotifier channel for the given root until the channel is
 // closed, the context hits cancellation/timeout, or notifications have been received for all the missing sidecars.
 func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed interfaces.ReadOnlySignedBeaconBlock) error {
+	if coreTime.PeerDASIsActive(signed.Block().Slot()) {
+		return s.areDataColumnsAvailable(ctx, root, signed)
+	}
+
 	if signed.Version() < version.Deneb {
 		return nil
 	}
@@ -546,9 +593,9 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int
 		return nil
 	}
 	// get a map of BlobSidecar indices that are not currently available.
-	missing, err := missingIndices(s.blobStorage, root, kzgCommitments)
+	missing, err := missingIndices(s.blobStorage, root, kzgCommitments, block.Slot())
 	if err != nil {
-		return err
+		return errors.Wrap(err, "missing indices")
 	}
 	// If there are no missing indices, all BlobSidecars are available.
 	if len(missing) == 0 {
@@ -557,7 +604,7 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int

 	// The gossip handler for blobs writes the index of each verified blob referencing the given
 	// root to the channel returned by blobNotifiers.forRoot.
-	nc := s.blobNotifiers.forRoot(root)
+	nc := s.blobNotifiers.forRoot(root, block.Slot())

 	// Log for DA checks that cross over into the next slot; helpful for debugging.
 	nextSlot := slots.BeginsAt(signed.Block().Slot()+1, s.genesisTime)
@@ -567,8 +614,13 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int
 			if len(missing) == 0 {
 				return
 			}
-			log.WithFields(daCheckLogFields(root, signed.Block().Slot(), expected, len(missing))).
-				Error("Still waiting for DA check at slot end.")
+
+			log.WithFields(logrus.Fields{
+				"slot":          signed.Block().Slot(),
+				"root":          fmt.Sprintf("%#x", root),
+				"blobsExpected": expected,
+				"blobsWaiting":  len(missing),
+			}).Error("Still waiting for blobs DA check at slot end.")
 		})
 		defer nst.Stop()
 	}
@@ -590,12 +642,176 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int
 	}
 }

-func daCheckLogFields(root [32]byte, slot primitives.Slot, expected, missing int) logrus.Fields {
-	return logrus.Fields{
-		"slot":          slot,
-		"root":          fmt.Sprintf("%#x", root),
-		"blobsExpected": expected,
-		"blobsWaiting":  missing,
+// uint64MapToSortedSlice produces a sorted uint64 slice from a map.
+func uint64MapToSortedSlice(input map[uint64]bool) []uint64 {
+	output := make([]uint64, 0, len(input))
+	for idx := range input {
+		output = append(output, idx)
+	}
+	slices.Sort[[]uint64](output)
+	return output
+}
+
+func (s *Service) areDataColumnsAvailable(ctx context.Context, root [32]byte, signed interfaces.ReadOnlySignedBeaconBlock) error {
+	if signed.Version() < version.Fulu {
+		return nil
+	}
+
+	block := signed.Block()
+	if block == nil {
+		return errors.New("invalid nil beacon block")
+	}
+
+	// We are only required to check within MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS
+	blockSlot, currentSlot := block.Slot(), s.CurrentSlot()
+	blockEpoch, currentEpoch := slots.ToEpoch(blockSlot), slots.ToEpoch(currentSlot)
+
+	if !params.WithinDAPeriod(blockEpoch, currentEpoch) {
+		return nil
+	}
+
+	body := block.Body()
+	if body == nil {
+		return errors.New("invalid nil beacon block body")
+	}
+
+	kzgCommitments, err := body.BlobKzgCommitments()
+	if err != nil {
+		return errors.Wrap(err, "blob KZG commitments")
+	}
+
+	// If block has not commitments there is nothing to wait for.
+	if len(kzgCommitments) == 0 {
+		return nil
+	}
+
+	// All columns to sample need to be available for the block to be considered available.
+	// https://github.com/ethereum/consensus-specs/blob/v1.5.0-alpha.10/specs/fulu/das-core.md#custody-sampling
+	nodeID := s.cfg.P2P.NodeID()
+	custodyGroupSamplingSize := peerdas.CustodyGroupSamplingSize()
+
+	custodyGroups, err := peerdas.CustodyGroups(nodeID, custodyGroupSamplingSize)
+	if err != nil {
+		return errors.Wrap(err, "custody groups")
+	}
+
+	// Exit early if the node is not expected to custody any data columns.
+	if len(custodyGroups) == 0 {
+		return nil
+	}
+
+	// Get the custody columns from the groups.
+	columnsMap, err := peerdas.CustodyColumns(custodyGroups)
+	if err != nil {
+		return errors.Wrap(err, "custody columns")
+	}
+
+	// Subscribe to newsly data columns stored in the database.
+	rootIndexChan := make(chan filesystem.RootIndexPair)
+	subscription := s.blobStorage.DataColumnFeed.Subscribe(rootIndexChan)
+	defer subscription.Unsubscribe()
+
+	// Get the count of data columns we already have in the store.
+	retrievedDataColumns, err := s.blobStorage.ColumnIndices(root)
+	if err != nil {
+		return errors.Wrap(err, "column indices")
+	}
+
+	retrievedDataColumnsCount := uint64(len(retrievedDataColumns))
+
+	// As soon as we have more than half of the data columns, we can reconstruct the missing ones.
+	// We don't need to wait for the rest of the data columns to declare the block as available.
+	if peerdas.CanSelfReconstruct(retrievedDataColumnsCount) {
+		return nil
+	}
+
+	// Get a map of data column indices that are not currently available.
+	missingMap, err := missingDataColumns(s.blobStorage, root, columnsMap)
+	if err != nil {
+		return err
+	}
+
+	// If there are no missing indices, all data column sidecars are available.
+	// This is the happy path.
+	if len(missingMap) == 0 {
+		return nil
+	}
+
+	// Log for DA checks that cross over into the next slot; helpful for debugging.
+	nextSlot := slots.BeginsAt(signed.Block().Slot()+1, s.genesisTime)
+	// Avoid logging if DA check is called after next slot start.
+	if nextSlot.After(time.Now()) {
+		nst := time.AfterFunc(time.Until(nextSlot), func() {
+			missingMapCount := uint64(len(missingMap))
+
+			if missingMapCount == 0 {
+				return
+			}
+
+			var (
+				expected interface{} = "all"
+				missing  interface{} = "all"
+			)
+
+			numberOfColumns := params.BeaconConfig().NumberOfColumns
+			colMapCount := uint64(len(columnsMap))
+
+			if colMapCount < numberOfColumns {
+				expected = uint64MapToSortedSlice(columnsMap)
+			}
+
+			if missingMapCount < numberOfColumns {
+				missing = uint64MapToSortedSlice(missingMap)
+			}
+
+			log.WithFields(logrus.Fields{
+				"slot":            signed.Block().Slot(),
+				"root":            fmt.Sprintf("%#x", root),
+				"columnsExpected": expected,
+				"columnsWaiting":  missing,
+			}).Error("Some data columns are still unavailable at slot end")
+		})
+
+		defer nst.Stop()
+	}
+
+	for {
+		select {
+		case rootIndex := <-rootIndexChan:
+			if rootIndex.Root != root {
+				// This is not the root we are looking for.
+				continue
+			}
+
+			// This is a data column we are expecting.
+			if _, ok := missingMap[rootIndex.Index]; ok {
+				retrievedDataColumnsCount++
+			}
+
+			// As soon as we have more than half of the data columns, we can reconstruct the missing ones.
+			// We don't need to wait for the rest of the data columns to declare the block as available.
+			if peerdas.CanSelfReconstruct(retrievedDataColumnsCount) {
+				return nil
+			}
+
+			// Remove the index from the missing map.
+			delete(missingMap, rootIndex.Index)
+
+			// Exit if there is no more missing data columns.
+			if len(missingMap) == 0 {
+				return nil
+			}
+		case <-ctx.Done():
+			var missingIndices interface{} = "all"
+			numberOfColumns := params.BeaconConfig().NumberOfColumns
+			missingIndicesCount := uint64(len(missingMap))
+
+			if missingIndicesCount < numberOfColumns {
+				missingIndices = uint64MapToSortedSlice(missingMap)
+			}
+
+			return errors.Wrapf(ctx.Err(), "data column sidecars slot: %d, BlockRoot: %#x, missing %v", block.Slot(), root, missingIndices)
+		}
 	}
 }

@@ -614,9 +830,6 @@ func (s *Service) lateBlockTasks(ctx context.Context) {
 	if !s.inRegularSync() {
 		return
 	}
-	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
-		Type: statefeed.MissedSlot,
-	})
 	s.headLock.RLock()
 	headRoot := s.headRoot()
 	headState := s.headState(ctx)
@@ -644,6 +857,13 @@ func (s *Service) lateBlockTasks(ctx context.Context) {
 	attribute := s.getPayloadAttribute(ctx, headState, s.CurrentSlot()+1, headRoot[:])
 	// return early if we are not proposing next slot
 	if attribute.IsEmpty() {
+		fcuArgs := &fcuConfig{
+			headState:  headState,
+			headRoot:   headRoot,
+			headBlock:  nil,
+			attributes: attribute,
+		}
+		go firePayloadAttributesEvent(ctx, s.cfg.StateNotifier.StateFeed(), fcuArgs)
 		return
 	}

@@ -678,9 +898,21 @@ func (s *Service) waitForSync() error {
 	}
 }

-func (s *Service) handleInvalidExecutionError(ctx context.Context, err error, blockRoot [32]byte, parentRoot [32]byte) error {
+func (s *Service) handleInvalidExecutionError(ctx context.Context, err error, blockRoot, parentRoot [32]byte) error {
 	if IsInvalidBlock(err) && InvalidBlockLVH(err) != [32]byte{} {
 		return s.pruneInvalidBlock(ctx, blockRoot, parentRoot, InvalidBlockLVH(err))
 	}
 	return err
 }
+
+// In the event of an issue processing a block we rollback changes done to the db and our caches
+// to always ensure that the node's internal state is consistent.
+func (s *Service) rollbackBlock(ctx context.Context, blockRoot [32]byte) {
+	log.Warnf("Rolling back insertion of block with root %#x due to processing error", blockRoot)
+	if err := s.cfg.StateGen.DeleteStateFromCaches(ctx, blockRoot); err != nil {
+		log.WithError(err).Errorf("Could not delete state from caches with block root %#x", blockRoot)
+	}
+	if err := s.cfg.BeaconDB.DeleteBlock(ctx, blockRoot); err != nil {
+		log.WithError(err).Errorf("Could not delete block with block root %#x", blockRoot)
+	}
+}
--- a/beacon-chain/blockchain/process_block_helpers.go
+++ b/beacon-chain/blockchain/process_block_helpers.go
@@ -1,8 +1,10 @@
 package blockchain

 import (
+	"bytes"
 	"context"
 	"fmt"
+	"strings"
 	"time"

 	lightclient "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/light-client"
@@ -15,15 +17,14 @@ import (
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/features"
 	field_params "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
+	consensus_blocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	mathutil "github.com/prysmaticlabs/prysm/v5/math"
 	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
-	ethpbv2 "github.com/prysmaticlabs/prysm/v5/proto/eth/v2"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
 	"github.com/sirupsen/logrus"
@@ -42,7 +43,7 @@ func (s *Service) getFCUArgs(cfg *postBlockProcessConfig, fcuArgs *fcuConfig) er
 	if !s.inRegularSync() {
 		return nil
 	}
-	slot := cfg.signed.Block().Slot()
+	slot := cfg.roblock.Block().Slot()
 	if slots.WithinVotingWindow(uint64(s.genesisTime.Unix()), slot) {
 		return nil
 	}
@@ -50,9 +51,9 @@ func (s *Service) getFCUArgs(cfg *postBlockProcessConfig, fcuArgs *fcuConfig) er
 }

 func (s *Service) getFCUArgsEarlyBlock(cfg *postBlockProcessConfig, fcuArgs *fcuConfig) error {
-	if cfg.blockRoot == cfg.headRoot {
+	if cfg.roblock.Root() == cfg.headRoot {
 		fcuArgs.headState = cfg.postState
-		fcuArgs.headBlock = cfg.signed
+		fcuArgs.headBlock = cfg.roblock
 		fcuArgs.headRoot = cfg.headRoot
 		fcuArgs.proposingSlot = s.CurrentSlot() + 1
 		return nil
@@ -96,7 +97,7 @@ func (s *Service) fcuArgsNonCanonicalBlock(cfg *postBlockProcessConfig, fcuArgs

 // sendStateFeedOnBlock sends an event that a new block has been synced
 func (s *Service) sendStateFeedOnBlock(cfg *postBlockProcessConfig) {
-	optimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(cfg.blockRoot)
+	optimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(cfg.roblock.Root())
 	if err != nil {
 		log.WithError(err).Debug("Could not check if block is optimistic")
 		optimistic = true
@@ -105,135 +106,209 @@ func (s *Service) sendStateFeedOnBlock(cfg *postBlockProcessConfig) {
 	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.BlockProcessed,
 		Data: &statefeed.BlockProcessedData{
-			Slot:        cfg.signed.Block().Slot(),
-			BlockRoot:   cfg.blockRoot,
-			SignedBlock: cfg.signed,
+			Slot:        cfg.roblock.Block().Slot(),
+			BlockRoot:   cfg.roblock.Root(),
+			SignedBlock: cfg.roblock,
 			Verified:    true,
 			Optimistic:  optimistic,
 		},
 	})
 }

-// sendLightClientFeeds sends the light client feeds when feature flag is enabled.
-func (s *Service) sendLightClientFeeds(cfg *postBlockProcessConfig) {
-	if features.Get().EnableLightClient {
-		if _, err := s.sendLightClientOptimisticUpdate(cfg.ctx, cfg.signed, cfg.postState); err != nil {
-			log.WithError(err).Error("Failed to send light client optimistic update")
-		}
-
-		// Get the finalized checkpoint
-		finalized := s.ForkChoicer().FinalizedCheckpoint()
-
-		// LightClientFinalityUpdate needs super majority
-		s.tryPublishLightClientFinalityUpdate(cfg.ctx, cfg.signed, finalized, cfg.postState)
+func (s *Service) processLightClientUpdates(cfg *postBlockProcessConfig) {
+	if err := s.processLightClientOptimisticUpdate(cfg.ctx, cfg.roblock, cfg.postState); err != nil {
+		log.WithError(err).Error("Failed to process light client optimistic update")
+	}
+	if err := s.processLightClientFinalityUpdate(cfg.ctx, cfg.roblock, cfg.postState); err != nil {
+		log.WithError(err).Error("Failed to process light client finality update")
 	}
 }

-func (s *Service) tryPublishLightClientFinalityUpdate(ctx context.Context, signed interfaces.ReadOnlySignedBeaconBlock, finalized *forkchoicetypes.Checkpoint, postState state.BeaconState) {
-	if finalized.Epoch <= s.lastPublishedLightClientEpoch {
-		return
-	}
-
-	config := params.BeaconConfig()
-	if finalized.Epoch < config.AltairForkEpoch {
-		return
-	}
-
-	syncAggregate, err := signed.Block().Body().SyncAggregate()
-	if err != nil || syncAggregate == nil {
-		return
-	}
-
-	// LightClientFinalityUpdate needs super majority
-	if syncAggregate.SyncCommitteeBits.Count()*3 < config.SyncCommitteeSize*2 {
-		return
-	}
-
-	_, err = s.sendLightClientFinalityUpdate(ctx, signed, postState)
+// saveLightClientUpdate saves the light client update for this block
+// if it's better than the already saved one, when feature flag is enabled.
+func (s *Service) saveLightClientUpdate(cfg *postBlockProcessConfig) {
+	attestedRoot := cfg.roblock.Block().ParentRoot()
+	attestedBlock, err := s.getBlock(cfg.ctx, attestedRoot)
 	if err != nil {
-		log.WithError(err).Error("Failed to send light client finality update")
+		log.WithError(err).Errorf("Saving light client update failed: Could not get attested block for root %#x", attestedRoot)
+		return
+	}
+	if attestedBlock == nil || attestedBlock.IsNil() {
+		log.Error("Saving light client update failed: Attested block is nil")
+		return
+	}
+	attestedState, err := s.cfg.StateGen.StateByRoot(cfg.ctx, attestedRoot)
+	if err != nil {
+		log.WithError(err).Errorf("Saving light client update failed: Could not get attested state for root %#x", attestedRoot)
+		return
+	}
+	if attestedState == nil || attestedState.IsNil() {
+		log.Error("Saving light client update failed: Attested state is nil")
+		return
+	}
+
+	finalizedRoot := attestedState.FinalizedCheckpoint().Root
+	finalizedBlock, err := s.getBlock(cfg.ctx, [32]byte(finalizedRoot))
+	if err != nil {
+		if errors.Is(err, errBlockNotFoundInCacheOrDB) {
+			log.Debugf("Skipping saving light client update: Finalized block is nil for root %#x", finalizedRoot)
+		} else {
+			log.WithError(err).Errorf("Saving light client update failed: Could not get finalized block for root %#x", finalizedRoot)
+		}
+		return
+	}
+
+	update, err := lightclient.NewLightClientUpdateFromBeaconState(
+		cfg.ctx,
+		s.CurrentSlot(),
+		cfg.postState,
+		cfg.roblock,
+		attestedState,
+		attestedBlock,
+		finalizedBlock,
+	)
+	if err != nil {
+		log.WithError(err).Error("Saving light client update failed: Could not create light client update")
+		return
+	}
+
+	period := slots.SyncCommitteePeriod(slots.ToEpoch(attestedState.Slot()))
+
+	oldUpdate, err := s.cfg.BeaconDB.LightClientUpdate(cfg.ctx, period)
+	if err != nil {
+		log.WithError(err).Error("Saving light client update failed: Could not get current light client update")
+		return
+	}
+
+	if oldUpdate == nil {
+		if err := s.cfg.BeaconDB.SaveLightClientUpdate(cfg.ctx, period, update); err != nil {
+			log.WithError(err).Error("Saving light client update failed: Could not save light client update")
+		} else {
+			log.WithField("period", period).Debug("Saving light client update: Saved new update")
+		}
+		return
+	}
+
+	isNewUpdateBetter, err := lightclient.IsBetterUpdate(update, oldUpdate)
+	if err != nil {
+		log.WithError(err).Error("Saving light client update failed: Could not compare light client updates")
+		return
+	}
+
+	if isNewUpdateBetter {
+		if err := s.cfg.BeaconDB.SaveLightClientUpdate(cfg.ctx, period, update); err != nil {
+			log.WithError(err).Error("Saving light client update failed: Could not save light client update")
+		} else {
+			log.WithField("period", period).Debug("Saving light client update: Saved new update")
+		}
 	} else {
-		s.lastPublishedLightClientEpoch = finalized.Epoch
+		log.WithField("period", period).Debug("Saving light client update: New update is not better than the current one. Skipping save.")
 	}
 }

-// sendLightClientFinalityUpdate sends a light client finality update notification to the state feed.
-func (s *Service) sendLightClientFinalityUpdate(ctx context.Context, signed interfaces.ReadOnlySignedBeaconBlock,
-	postState state.BeaconState) (int, error) {
-	// Get attested state
+// saveLightClientBootstrap saves a light client bootstrap for this block
+// when feature flag is enabled.
+func (s *Service) saveLightClientBootstrap(cfg *postBlockProcessConfig) {
+	blockRoot := cfg.roblock.Root()
+	bootstrap, err := lightclient.NewLightClientBootstrapFromBeaconState(cfg.ctx, s.CurrentSlot(), cfg.postState, cfg.roblock)
+	if err != nil {
+		log.WithError(err).Error("Saving light client bootstrap failed: Could not create light client bootstrap")
+		return
+	}
+	err = s.cfg.BeaconDB.SaveLightClientBootstrap(cfg.ctx, blockRoot[:], bootstrap)
+	if err != nil {
+		log.WithError(err).Error("Saving light client bootstrap failed: Could not save light client bootstrap in DB")
+	}
+}
+
+func (s *Service) processLightClientFinalityUpdate(
+	ctx context.Context,
+	signed interfaces.ReadOnlySignedBeaconBlock,
+	postState state.BeaconState,
+) error {
 	attestedRoot := signed.Block().ParentRoot()
+	attestedBlock, err := s.cfg.BeaconDB.Block(ctx, attestedRoot)
+	if err != nil {
+		return errors.Wrapf(err, "could not get attested block for root %#x", attestedRoot)
+	}
 	attestedState, err := s.cfg.StateGen.StateByRoot(ctx, attestedRoot)
 	if err != nil {
-		return 0, errors.Wrap(err, "could not get attested state")
+		return errors.Wrapf(err, "could not get attested state for root %#x", attestedRoot)
 	}

-	// Get finalized block
-	var finalizedBlock interfaces.ReadOnlySignedBeaconBlock
-	finalizedCheckPoint := attestedState.FinalizedCheckpoint()
-	if finalizedCheckPoint != nil {
-		finalizedRoot := bytesutil.ToBytes32(finalizedCheckPoint.Root)
-		finalizedBlock, err = s.cfg.BeaconDB.Block(ctx, finalizedRoot)
-		if err != nil {
-			finalizedBlock = nil
+	finalizedCheckpoint := attestedState.FinalizedCheckpoint()
+
+	// Check if the finalized checkpoint has changed
+	if finalizedCheckpoint == nil || bytes.Equal(finalizedCheckpoint.GetRoot(), postState.FinalizedCheckpoint().Root) {
+		return nil
+	}
+
+	finalizedRoot := bytesutil.ToBytes32(finalizedCheckpoint.Root)
+	finalizedBlock, err := s.cfg.BeaconDB.Block(ctx, finalizedRoot)
+	if err != nil {
+		if errors.Is(err, errBlockNotFoundInCacheOrDB) {
+			log.Debugf("Skipping processing light client finality update: Finalized block is nil for root %#x", finalizedRoot)
+			return nil
 		}
+		return errors.Wrapf(err, "could not get finalized block for root %#x", finalizedRoot)
 	}

 	update, err := lightclient.NewLightClientFinalityUpdateFromBeaconState(
 		ctx,
+		postState.Slot(),
 		postState,
 		signed,
 		attestedState,
+		attestedBlock,
 		finalizedBlock,
 	)

 	if err != nil {
-		return 0, errors.Wrap(err, "could not create light client update")
+		return errors.Wrap(err, "could not create light client finality update")
 	}

-	// Return the result
-	result := &ethpbv2.LightClientFinalityUpdateWithVersion{
-		Version: ethpbv2.Version(signed.Version()),
-		Data:    update,
-	}
-
-	// Send event
-	return s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
+	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.LightClientFinalityUpdate,
-		Data: result,
-	}), nil
+		Data: update,
+	})
+	return nil
 }

-// sendLightClientOptimisticUpdate sends a light client optimistic update notification to the state feed.
-func (s *Service) sendLightClientOptimisticUpdate(ctx context.Context, signed interfaces.ReadOnlySignedBeaconBlock,
-	postState state.BeaconState) (int, error) {
-	// Get attested state
+func (s *Service) processLightClientOptimisticUpdate(ctx context.Context, signed interfaces.ReadOnlySignedBeaconBlock,
+	postState state.BeaconState) error {
 	attestedRoot := signed.Block().ParentRoot()
+	attestedBlock, err := s.cfg.BeaconDB.Block(ctx, attestedRoot)
+	if err != nil {
+		return errors.Wrapf(err, "could not get attested block for root %#x", attestedRoot)
+	}
 	attestedState, err := s.cfg.StateGen.StateByRoot(ctx, attestedRoot)
 	if err != nil {
-		return 0, errors.Wrap(err, "could not get attested state")
+		return errors.Wrapf(err, "could not get attested state for root %#x", attestedRoot)
 	}

 	update, err := lightclient.NewLightClientOptimisticUpdateFromBeaconState(
 		ctx,
+		postState.Slot(),
 		postState,
 		signed,
 		attestedState,
+		attestedBlock,
 	)

 	if err != nil {
-		return 0, errors.Wrap(err, "could not create light client update")
+		if strings.Contains(err.Error(), lightclient.ErrNotEnoughSyncCommitteeBits) {
+			log.WithError(err).Debug("Skipping processing light client optimistic update")
+			return nil
+		}
+		return errors.Wrap(err, "could not create light client optimistic update")
 	}

-	// Return the result
-	result := &ethpbv2.LightClientOptimisticUpdateWithVersion{
-		Version: ethpbv2.Version(signed.Version()),
-		Data:    update,
-	}
-
-	return s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
+	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.LightClientOptimisticUpdate,
-		Data: result,
-	}), nil
+		Data: update,
+	})
+
+	return nil
 }

 // updateCachesPostBlockProcessing updates the next slot cache and handles the epoch
@@ -242,20 +317,21 @@ func (s *Service) sendLightClientOptimisticUpdate(ctx context.Context, signed in
 // before sending FCU to the engine.
 func (s *Service) updateCachesPostBlockProcessing(cfg *postBlockProcessConfig) error {
 	slot := cfg.postState.Slot()
-	if err := transition.UpdateNextSlotCache(cfg.ctx, cfg.blockRoot[:], cfg.postState); err != nil {
+	root := cfg.roblock.Root()
+	if err := transition.UpdateNextSlotCache(cfg.ctx, root[:], cfg.postState); err != nil {
 		return errors.Wrap(err, "could not update next slot state cache")
 	}
 	if !slots.IsEpochEnd(slot) {
 		return nil
 	}
-	return s.handleEpochBoundary(cfg.ctx, slot, cfg.postState, cfg.blockRoot[:])
+	return s.handleEpochBoundary(cfg.ctx, slot, cfg.postState, root[:])
 }

 // handleSecondFCUCall handles a second call to FCU when syncing a new block.
 // This is useful when proposing in the next block and we want to defer the
 // computation of the next slot shuffling.
 func (s *Service) handleSecondFCUCall(cfg *postBlockProcessConfig, fcuArgs *fcuConfig) {
-	if (fcuArgs.attributes == nil || fcuArgs.attributes.IsEmpty()) && cfg.headRoot == cfg.blockRoot {
+	if (fcuArgs.attributes == nil || fcuArgs.attributes.IsEmpty()) && cfg.headRoot == cfg.roblock.Root() {
 		go s.sendFCUWithAttributes(cfg, fcuArgs)
 	}
 }
@@ -271,7 +347,7 @@ func reportProcessingTime(startTime time.Time) {
 // called on blocks that arrive after the attestation voting window, or in a
 // background routine after syncing early blocks.
 func (s *Service) computePayloadAttributes(cfg *postBlockProcessConfig, fcuArgs *fcuConfig) error {
-	if cfg.blockRoot == cfg.headRoot {
+	if cfg.roblock.Root() == cfg.headRoot {
 		if err := s.updateCachesPostBlockProcessing(cfg); err != nil {
 			return err
 		}
@@ -428,7 +504,7 @@ func (s *Service) ancestorByDB(ctx context.Context, r [32]byte, slot primitives.

 // This retrieves missing blocks from DB (ie. the blocks that couldn't be received over sync) and inserts them to fork choice store.
 // This is useful for block tree visualizer and additional vote accounting.
-func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfaces.ReadOnlyBeaconBlock,
+func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, signed interfaces.ReadOnlySignedBeaconBlock,
 	fCheckpoint, jCheckpoint *ethpb.Checkpoint) error {
 	pendingNodes := make([]*forkchoicetypes.BlockAndCheckpoints, 0)

@@ -438,10 +514,15 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfa
 	if err != nil {
 		return err
 	}
-	pendingNodes = append(pendingNodes, &forkchoicetypes.BlockAndCheckpoints{Block: blk,
+	// The first block can have a bogus root since the block is not inserted in forkchoice
+	roblock, err := consensus_blocks.NewROBlockWithRoot(signed, [32]byte{})
+	if err != nil {
+		return err
+	}
+	pendingNodes = append(pendingNodes, &forkchoicetypes.BlockAndCheckpoints{Block: roblock,
 		JustifiedCheckpoint: jCheckpoint, FinalizedCheckpoint: fCheckpoint})
 	// As long as parent node is not in fork choice store, and parent node is in DB.
-	root := blk.ParentRoot()
+	root := roblock.Block().ParentRoot()
 	for !s.cfg.ForkChoiceStore.HasNode(root) && s.cfg.BeaconDB.HasBlock(ctx, root) {
 		b, err := s.getBlock(ctx, root)
 		if err != nil {
@@ -450,8 +531,12 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfa
 		if b.Block().Slot() <= fSlot {
 			break
 		}
+		roblock, err := consensus_blocks.NewROBlockWithRoot(b, root)
+		if err != nil {
+			return err
+		}
 		root = b.Block().ParentRoot()
-		args := &forkchoicetypes.BlockAndCheckpoints{Block: b.Block(),
+		args := &forkchoicetypes.BlockAndCheckpoints{Block: roblock,
 			JustifiedCheckpoint: jCheckpoint,
 			FinalizedCheckpoint: fCheckpoint}
 		pendingNodes = append(pendingNodes, args)
--- a/beacon-chain/blockchain/process_block_test.go
+++ b/beacon-chain/blockchain/process_block_test.go
--- a/beacon-chain/blockchain/receive_attestation.go
+++ b/beacon-chain/blockchain/receive_attestation.go
@@ -9,6 +9,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/v5/config/features"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
@@ -166,7 +167,13 @@ func (s *Service) UpdateHead(ctx context.Context, proposingSlot primitives.Slot)

 // This processes fork choice attestations from the pool to account for validator votes and fork choice.
 func (s *Service) processAttestations(ctx context.Context, disparity time.Duration) {
-	atts := s.cfg.AttPool.ForkchoiceAttestations()
+	var atts []ethpb.Att
+	if features.Get().EnableExperimentalAttestationPool {
+		atts = s.cfg.AttestationCache.ForkchoiceAttestations()
+	} else {
+		atts = s.cfg.AttPool.ForkchoiceAttestations()
+	}
+
 	for _, a := range atts {
 		// Based on the spec, don't process the attestation until the subsequent slot.
 		// This delays consideration in the fork choice until their slot is in the past.
@@ -182,7 +189,11 @@ func (s *Service) processAttestations(ctx context.Context, disparity time.Durati
 			continue
 		}

-		if err := s.cfg.AttPool.DeleteForkchoiceAttestation(a); err != nil {
+		if features.Get().EnableExperimentalAttestationPool {
+			if err := s.cfg.AttestationCache.DeleteForkchoiceAttestation(a); err != nil {
+				log.WithError(err).Error("Could not delete fork choice attestation in pool")
+			}
+		} else if err := s.cfg.AttPool.DeleteForkchoiceAttestation(a); err != nil {
 			log.WithError(err).Error("Could not delete fork choice attestation in pool")
 		}

--- a/beacon-chain/blockchain/receive_attestation_test.go
+++ b/beacon-chain/blockchain/receive_attestation_test.go
@@ -46,7 +46,7 @@ func TestVerifyLMDFFGConsistent(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, r32))

-	state, r33, err := prepareForkchoiceState(ctx, 33, [32]byte{'b'}, r32, params.BeaconConfig().ZeroHash, fc, fc)
+	state, r33, err := prepareForkchoiceState(ctx, 33, [32]byte{'b'}, r32.Root(), params.BeaconConfig().ZeroHash, fc, fc)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, r33))

@@ -54,10 +54,12 @@ func TestVerifyLMDFFGConsistent(t *testing.T) {
 	a := util.NewAttestation()
 	a.Data.Target.Epoch = 1
 	a.Data.Target.Root = []byte{'c'}
-	a.Data.BeaconBlockRoot = r33[:]
+	r33Root := r33.Root()
+	a.Data.BeaconBlockRoot = r33Root[:]
 	require.ErrorContains(t, wanted, service.VerifyLmdFfgConsistency(context.Background(), a))

-	a.Data.Target.Root = r32[:]
+	r32Root := r32.Root()
+	a.Data.Target.Root = r32Root[:]
 	err = service.VerifyLmdFfgConsistency(context.Background(), a)
 	require.NoError(t, err, "Could not verify LMD and FFG votes to be consistent")
 }
@@ -84,9 +86,7 @@ func TestProcessAttestations_Ok(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
 	attsToSave := make([]ethpb.Att, len(atts))
-	for i, a := range atts {
-		attsToSave[i] = a
-	}
+	copy(attsToSave, atts)
 	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(attsToSave))
 	service.processAttestations(ctx, 0)
 	require.Equal(t, 0, len(service.cfg.AttPool.ForkchoiceAttestations()))
@@ -116,7 +116,9 @@ func TestService_ProcessAttestationsAndUpdateHead(t *testing.T) {
 	postState, err := service.validateStateTransition(ctx, preState, wsb)
 	require.NoError(t, err)
 	require.NoError(t, service.savePostStateInfo(ctx, tRoot, wsb, postState))
-	require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, wsb, tRoot, [32]byte{}, postState, false}))
+	roblock, err := blocks.NewROBlockWithRoot(wsb, tRoot)
+	require.NoError(t, err)
+	require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, roblock, [32]byte{}, postState, false}))
 	copied, err = service.cfg.StateGen.StateByRoot(ctx, tRoot)
 	require.NoError(t, err)
 	require.Equal(t, 2, fcs.NodeCount())
@@ -126,9 +128,7 @@ func TestService_ProcessAttestationsAndUpdateHead(t *testing.T) {
 	atts, err := util.GenerateAttestations(copied, pks, 1, 1, false)
 	require.NoError(t, err)
 	attsToSave := make([]ethpb.Att, len(atts))
-	for i, a := range atts {
-		attsToSave[i] = a
-	}
+	copy(attsToSave, atts)
 	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(attsToSave))
 	// Verify the target is in forkchoice
 	require.Equal(t, true, fcs.HasNode(bytesutil.ToBytes32(atts[0].GetData().BeaconBlockRoot)))
@@ -176,7 +176,9 @@ func TestService_UpdateHead_NoAtts(t *testing.T) {
 	postState, err := service.validateStateTransition(ctx, preState, wsb)
 	require.NoError(t, err)
 	require.NoError(t, service.savePostStateInfo(ctx, tRoot, wsb, postState))
-	require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, wsb, tRoot, [32]byte{}, postState, false}))
+	roblock, err := blocks.NewROBlockWithRoot(wsb, tRoot)
+	require.NoError(t, err)
+	require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, roblock, [32]byte{}, postState, false}))
 	require.Equal(t, 2, fcs.NodeCount())
 	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	require.Equal(t, tRoot, service.head.root)
--- a/beacon-chain/blockchain/receive_blob.go
+++ b/beacon-chain/blockchain/receive_blob.go
@@ -4,12 +4,13 @@ import (
 	"context"

 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 )

 // SendNewBlobEvent sends a message to the BlobNotifier channel that the blob
 // for the block root `root` is ready in the database
-func (s *Service) sendNewBlobEvent(root [32]byte, index uint64) {
-	s.blobNotifiers.notifyIndex(root, index)
+func (s *Service) sendNewBlobEvent(root [32]byte, index uint64, slot primitives.Slot) {
+	s.blobNotifiers.notifyIndex(root, index, slot)
 }

 // ReceiveBlob saves the blob to database and sends the new event
@@ -18,6 +19,6 @@ func (s *Service) ReceiveBlob(ctx context.Context, b blocks.VerifiedROBlob) erro
 		return err
 	}

-	s.sendNewBlobEvent(b.BlockRoot(), b.Index)
+	s.sendNewBlobEvent(b.BlockRoot(), b.Index, b.Slot())
 	return nil
 }
--- a/beacon-chain/blockchain/receive_block.go
+++ b/beacon-chain/blockchain/receive_block.go
@@ -51,6 +51,12 @@ type BlobReceiver interface {
 	ReceiveBlob(context.Context, blocks.VerifiedROBlob) error
 }

+// DataColumnReceiver interface defines the methods of chain service for receiving new
+// data columns
+type DataColumnReceiver interface {
+	ReceiveDataColumn(blocks.VerifiedRODataColumn) error
+}
+
 // SlashingReceiver interface defines the methods of chain service for receiving validated slashing over the wire.
 type SlashingReceiver interface {
 	ReceiveAttesterSlashing(ctx context.Context, slashing ethpb.AttSlashing)
@@ -69,6 +75,7 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 		log.WithField("blockRoot", fmt.Sprintf("%#x", blockRoot)).Debug("Ignoring already synced block")
 		return nil
 	}
+
 	receivedTime := time.Now()
 	s.blockBeingSynced.set(blockRoot)
 	defer s.blockBeingSynced.unset(blockRoot)
@@ -77,20 +84,28 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	if err != nil {
 		return err
 	}
+
 	preState, err := s.getBlockPreState(ctx, blockCopy.Block())
 	if err != nil {
 		return errors.Wrap(err, "could not get block's prestate")
 	}

 	currentCheckpoints := s.saveCurrentCheckpoints(preState)
-	postState, isValidPayload, err := s.validateExecutionAndConsensus(ctx, preState, blockCopy, blockRoot)
+	roblock, err := blocks.NewROBlockWithRoot(blockCopy, blockRoot)
 	if err != nil {
 		return err
 	}
+
+	postState, isValidPayload, err := s.validateExecutionAndConsensus(ctx, preState, roblock)
+	if err != nil {
+		return err
+	}
+
 	daWaitedTime, err := s.handleDA(ctx, blockCopy, blockRoot, avs)
 	if err != nil {
 		return err
 	}
+
 	// Defragment the state before continuing block processing.
 	s.defragmentState(postState)

@@ -102,8 +117,7 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	}
 	args := &postBlockProcessConfig{
 		ctx:            ctx,
-		signed:         blockCopy,
-		blockRoot:      blockRoot,
+		roblock:        roblock,
 		postState:      postState,
 		isValidPayload: isValidPayload,
 	}
@@ -184,8 +198,7 @@ func (s *Service) updateCheckpoints(
 func (s *Service) validateExecutionAndConsensus(
 	ctx context.Context,
 	preState state.BeaconState,
-	block interfaces.SignedBeaconBlock,
-	blockRoot [32]byte,
+	block blocks.ROBlock,
 ) (state.BeaconState, bool, error) {
 	preStateVersion, preStateHeader, err := getStateVersionAndPayload(preState)
 	if err != nil {
@@ -204,7 +217,7 @@ func (s *Service) validateExecutionAndConsensus(
 	var isValidPayload bool
 	eg.Go(func() error {
 		var err error
-		isValidPayload, err = s.validateExecutionOnBlock(ctx, preStateVersion, preStateHeader, block, blockRoot)
+		isValidPayload, err = s.validateExecutionOnBlock(ctx, preStateVersion, preStateHeader, block)
 		if err != nil {
 			return errors.Wrap(err, "could not notify the engine of the new payload")
 		}
@@ -228,12 +241,14 @@ func (s *Service) handleDA(
 		if err != nil {
 			return 0, err
 		}
-		if err := avs.IsDataAvailable(ctx, s.CurrentSlot(), rob); err != nil {
+
+		nodeID := s.cfg.P2P.NodeID()
+		if err := avs.IsDataAvailable(ctx, nodeID, s.CurrentSlot(), rob); err != nil {
 			return 0, errors.Wrap(err, "could not validate blob data availability (AvailabilityStore.IsDataAvailable)")
 		}
 	} else {
 		if err := s.isDataAvailable(ctx, blockRoot, block); err != nil {
-			return 0, errors.Wrap(err, "could not validate blob data availability")
+			return 0, errors.Wrap(err, "is data available")
 		}
 	}
 	daWaitedTime := time.Since(daStartTime)
@@ -273,7 +288,6 @@ func (s *Service) reportPostBlockProcessing(
 func (s *Service) executePostFinalizationTasks(ctx context.Context, finalizedState state.BeaconState) {
 	finalized := s.cfg.ForkChoiceStore.FinalizedCheckpoint()
 	go func() {
-		finalizedState.SaveValidatorIndices() // used to handle Validator index invariant from EIP6110
 		s.sendNewFinalizedEvent(ctx, finalizedState)
 	}()
 	depCtx, cancel := context.WithTimeout(context.Background(), depositDeadline)
@@ -350,6 +364,9 @@ func (s *Service) ReceiveBlockBatch(ctx context.Context, blocks []blocks.ROBlock

 // HasBlock returns true if the block of the input root exists in initial sync blocks cache or DB.
 func (s *Service) HasBlock(ctx context.Context, root [32]byte) bool {
+	if s.BlockBeingSynced(root) {
+		return false
+	}
 	return s.hasBlockInInitSyncOrDB(ctx, root)
 }

@@ -553,16 +570,16 @@ func (s *Service) sendBlockAttestationsToSlasher(signed interfaces.ReadOnlySigne
 }

 // validateExecutionOnBlock notifies the engine of the incoming block execution payload and returns true if the payload is valid
-func (s *Service) validateExecutionOnBlock(ctx context.Context, ver int, header interfaces.ExecutionData, signed interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte) (bool, error) {
-	isValidPayload, err := s.notifyNewPayload(ctx, ver, header, signed)
+func (s *Service) validateExecutionOnBlock(ctx context.Context, ver int, header interfaces.ExecutionData, block blocks.ROBlock) (bool, error) {
+	isValidPayload, err := s.notifyNewPayload(ctx, ver, header, block)
 	if err != nil {
 		s.cfg.ForkChoiceStore.Lock()
-		err = s.handleInvalidExecutionError(ctx, err, blockRoot, signed.Block().ParentRoot())
+		err = s.handleInvalidExecutionError(ctx, err, block.Root(), block.Block().ParentRoot())
 		s.cfg.ForkChoiceStore.Unlock()
 		return false, err
 	}
-	if signed.Version() < version.Capella && isValidPayload {
-		if err := s.validateMergeTransitionBlock(ctx, ver, header, signed); err != nil {
+	if block.Block().Version() < version.Capella && isValidPayload {
+		if err := s.validateMergeTransitionBlock(ctx, ver, header, block); err != nil {
 			return isValidPayload, err
 		}
 	}
--- a/beacon-chain/blockchain/receive_block_test.go
+++ b/beacon-chain/blockchain/receive_block_test.go
@@ -278,6 +278,8 @@ func TestService_HasBlock(t *testing.T) {
 	r, err = b.Block.HashTreeRoot()
 	require.NoError(t, err)
 	require.Equal(t, true, s.HasBlock(context.Background(), r))
+	s.blockBeingSynced.set(r)
+	require.Equal(t, false, s.HasBlock(context.Background(), r))
 }

 func TestCheckSaveHotStateDB_Enabling(t *testing.T) {
--- a/beacon-chain/blockchain/receive_data_column.go
+++ b/beacon-chain/blockchain/receive_data_column.go
@@ -0,0 +1,14 @@
+package blockchain
+
+import (
+	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
+)
+
+func (s *Service) ReceiveDataColumn(ds blocks.VerifiedRODataColumn) error {
+	if err := s.blobStorage.SaveDataColumn(ds); err != nil {
+		return errors.Wrap(err, "save data column")
+	}
+
+	return nil
+}
--- a/beacon-chain/blockchain/service.go
+++ b/beacon-chain/blockchain/service.go
@@ -48,25 +48,24 @@ import (
 // Service represents a service that handles the internal
 // logic of managing the full PoS beacon chain.
 type Service struct {
-	cfg                           *config
-	ctx                           context.Context
-	cancel                        context.CancelFunc
-	genesisTime                   time.Time
-	head                          *head
-	headLock                      sync.RWMutex
-	originBlockRoot               [32]byte // genesis root, or weak subjectivity checkpoint root, depending on how the node is initialized
-	boundaryRoots                 [][32]byte
-	checkpointStateCache          *cache.CheckpointStateCache
-	initSyncBlocks                map[[32]byte]interfaces.ReadOnlySignedBeaconBlock
-	initSyncBlocksLock            sync.RWMutex
-	wsVerifier                    *WeakSubjectivityVerifier
-	clockSetter                   startup.ClockSetter
-	clockWaiter                   startup.ClockWaiter
-	syncComplete                  chan struct{}
-	blobNotifiers                 *blobNotifierMap
-	blockBeingSynced              *currentlySyncingBlock
-	blobStorage                   *filesystem.BlobStorage
-	lastPublishedLightClientEpoch primitives.Epoch
+	cfg                  *config
+	ctx                  context.Context
+	cancel               context.CancelFunc
+	genesisTime          time.Time
+	head                 *head
+	headLock             sync.RWMutex
+	originBlockRoot      [32]byte // genesis root, or weak subjectivity checkpoint root, depending on how the node is initialized
+	boundaryRoots        [][32]byte
+	checkpointStateCache *cache.CheckpointStateCache
+	initSyncBlocks       map[[32]byte]interfaces.ReadOnlySignedBeaconBlock
+	initSyncBlocksLock   sync.RWMutex
+	wsVerifier           *WeakSubjectivityVerifier
+	clockSetter          startup.ClockSetter
+	clockWaiter          startup.ClockWaiter
+	syncComplete         chan struct{}
+	blobNotifiers        *blobNotifierMap
+	blockBeingSynced     *currentlySyncingBlock
+	blobStorage          *filesystem.BlobStorage
 }

 // config options for the service.
@@ -77,11 +76,12 @@ type config struct {
 	DepositCache            cache.DepositCache
 	PayloadIDCache          *cache.PayloadIDCache
 	TrackedValidatorsCache  *cache.TrackedValidatorsCache
+	AttestationCache        *cache.AttestationCache
 	AttPool                 attestations.Pool
 	ExitPool                voluntaryexits.PoolManager
 	SlashingPool            slashings.PoolManager
 	BLSToExecPool           blstoexec.PoolManager
-	P2p                     p2p.Broadcaster
+	P2P                     p2p.Acceser
 	MaxRoutines             int
 	StateNotifier           statefeed.Notifier
 	ForkChoiceStore         f.ForkChoicer
@@ -106,18 +106,26 @@ var ErrMissingClockSetter = errors.New("blockchain Service initialized without a
 type blobNotifierMap struct {
 	sync.RWMutex
 	notifiers map[[32]byte]chan uint64
-	seenIndex map[[32]byte][fieldparams.MaxBlobsPerBlock]bool
+	// TODO: Separate blobs from data columns
+	// seenIndex map[[32]byte][]bool
+	seenIndex map[[32]byte][fieldparams.NumberOfColumns]bool
 }

 // notifyIndex notifies a blob by its index for a given root.
 // It uses internal maps to keep track of seen indices and notifier channels.
-func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64) {
-	if idx >= fieldparams.MaxBlobsPerBlock {
-		return
-	}
+func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64, slot primitives.Slot) {
+	// TODO: Separate blobs from data columns
+	// maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
+	// if idx >= uint64(maxBlobsPerBlock) {
+	// 	return
+	// }

 	bn.Lock()
 	seen := bn.seenIndex[root]
+	// TODO: Separate blobs from data columns
+	// if seen == nil {
+	// seen = make([]bool, maxBlobsPerBlock)
+	// }
 	if seen[idx] {
 		bn.Unlock()
 		return
@@ -128,7 +136,9 @@ func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64) {
 	// Retrieve or create the notifier channel for the given root.
 	c, ok := bn.notifiers[root]
 	if !ok {
-		c = make(chan uint64, fieldparams.MaxBlobsPerBlock)
+		// TODO: Separate blobs from data columns
+		// c = make(chan uint64, maxBlobsPerBlock)
+		c = make(chan uint64, fieldparams.NumberOfColumns)
 		bn.notifiers[root] = c
 	}

@@ -137,12 +147,16 @@ func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64) {
 	c <- idx
 }

-func (bn *blobNotifierMap) forRoot(root [32]byte) chan uint64 {
+func (bn *blobNotifierMap) forRoot(root [32]byte, slot primitives.Slot) chan uint64 {
+	// TODO: Separate blobs from data columns
+	// maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
 	bn.Lock()
 	defer bn.Unlock()
 	c, ok := bn.notifiers[root]
 	if !ok {
-		c = make(chan uint64, fieldparams.MaxBlobsPerBlock)
+		// TODO: Separate blobs from data columns
+		// c = make(chan uint64, maxBlobsPerBlock)
+		c = make(chan uint64, fieldparams.NumberOfColumns)
 		bn.notifiers[root] = c
 	}
 	return c
@@ -168,7 +182,9 @@ func NewService(ctx context.Context, opts ...Option) (*Service, error) {
 	ctx, cancel := context.WithCancel(ctx)
 	bn := &blobNotifierMap{
 		notifiers: make(map[[32]byte]chan uint64),
-		seenIndex: make(map[[32]byte][fieldparams.MaxBlobsPerBlock]bool),
+		// TODO: Separate blobs from data columns
+		// seenIndex: make(map[[32]byte][]bool),
+		seenIndex: make(map[[32]byte][fieldparams.NumberOfColumns]bool),
 	}
 	srv := &Service{
 		ctx:                  ctx,
@@ -303,7 +319,15 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 	if err != nil {
 		return errors.Wrap(err, "could not get finalized checkpoint state")
 	}
-	if err := s.cfg.ForkChoiceStore.InsertNode(s.ctx, st, fRoot); err != nil {
+	finalizedBlock, err := s.cfg.BeaconDB.Block(s.ctx, fRoot)
+	if err != nil {
+		return errors.Wrap(err, "could not get finalized checkpoint block")
+	}
+	roblock, err := blocks.NewROBlockWithRoot(finalizedBlock, fRoot)
+	if err != nil {
+		return err
+	}
+	if err := s.cfg.ForkChoiceStore.InsertNode(s.ctx, st, roblock); err != nil {
 		return errors.Wrap(err, "could not insert finalized block to forkchoice")
 	}
 	if !features.Get().EnableStartOptimistic {
@@ -329,8 +353,6 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 		return errors.Wrap(err, "failed to initialize blockchain service")
 	}

-	saved.SaveValidatorIndices() // used to handle Validator index invariant from EIP6110
-
 	return nil
 }

@@ -517,7 +539,11 @@ func (s *Service) saveGenesisData(ctx context.Context, genesisState state.Beacon

 	s.cfg.ForkChoiceStore.Lock()
 	defer s.cfg.ForkChoiceStore.Unlock()
-	if err := s.cfg.ForkChoiceStore.InsertNode(ctx, genesisState, genesisBlkRoot); err != nil {
+	gb, err := blocks.NewROBlockWithRoot(genesisBlk, genesisBlkRoot)
+	if err != nil {
+		return err
+	}
+	if err := s.cfg.ForkChoiceStore.InsertNode(ctx, genesisState, gb); err != nil {
 		log.WithError(err).Fatal("Could not process genesis block for fork choice")
 	}
 	s.cfg.ForkChoiceStore.SetOriginRoot(genesisBlkRoot)
--- a/beacon-chain/blockchain/service_test.go
+++ b/beacon-chain/blockchain/service_test.go
@@ -97,13 +97,14 @@ func setupBeaconChain(t *testing.T, beaconDB db.Database) *Service {
 		WithAttestationPool(attestations.NewPool()),
 		WithSlashingPool(slashings.NewPool()),
 		WithExitPool(voluntaryexits.NewPool()),
-		WithP2PBroadcaster(&mockBroadcaster{}),
+		WithP2PBroadcaster(&mockAccesser{}),
 		WithStateNotifier(&mockBeaconNode{}),
 		WithForkChoiceStore(fc),
 		WithAttestationService(attService),
 		WithStateGen(stateGen),
 		WithPayloadIDCache(cache.NewPayloadIDCache()),
 		WithClockSynchronizer(startup.NewClockSynchronizer()),
+		WithP2PBroadcaster(&mockAccesser{}),
 	}

 	chainService, err := NewService(ctx, opts...)
@@ -376,11 +377,15 @@ func TestHasBlock_ForkChoiceAndDB_DoublyLinkedTree(t *testing.T) {
 		cfg: &config{ForkChoiceStore: doublylinkedtree.New(), BeaconDB: beaconDB},
 	}
 	b := util.NewBeaconBlock()
+	wsb, err := consensusblocks.NewSignedBeaconBlock(b)
+	require.NoError(t, err)
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
+	roblock, err := consensusblocks.NewROBlockWithRoot(wsb, r)
+	require.NoError(t, err)
 	beaconState, err := util.NewBeaconState()
 	require.NoError(t, err)
-	require.NoError(t, s.cfg.ForkChoiceStore.InsertNode(ctx, beaconState, r))
+	require.NoError(t, s.cfg.ForkChoiceStore.InsertNode(ctx, beaconState, roblock))

 	assert.Equal(t, false, s.hasBlock(ctx, [32]byte{}), "Should not have block")
 	assert.Equal(t, true, s.hasBlock(ctx, r), "Should have block")
@@ -453,7 +458,11 @@ func BenchmarkHasBlockForkChoiceStore_DoublyLinkedTree(b *testing.B) {
 	require.NoError(b, err)
 	beaconState, err := util.NewBeaconState()
 	require.NoError(b, err)
-	require.NoError(b, s.cfg.ForkChoiceStore.InsertNode(ctx, beaconState, r))
+	wsb, err := consensusblocks.NewSignedBeaconBlock(blk)
+	require.NoError(b, err)
+	roblock, err := consensusblocks.NewROBlockWithRoot(wsb, r)
+	require.NoError(b, err)
+	require.NoError(b, s.cfg.ForkChoiceStore.InsertNode(ctx, beaconState, roblock))

 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
@@ -579,7 +588,9 @@ func (s *MockClockSetter) SetClock(g *startup.Clock) error {
 func TestNotifyIndex(t *testing.T) {
 	// Initialize a blobNotifierMap
 	bn := &blobNotifierMap{
-		seenIndex: make(map[[32]byte][fieldparams.MaxBlobsPerBlock]bool),
+		// TODO: Separate blobs from data columns
+		// seenIndex: make(map[[32]byte][]bool),
+		seenIndex: make(map[[32]byte][fieldparams.NumberOfColumns]bool),
 		notifiers: make(map[[32]byte]chan uint64),
 	}

@@ -588,7 +599,7 @@ func TestNotifyIndex(t *testing.T) {
 	copy(root[:], "exampleRoot")

 	// Test notifying a new index
-	bn.notifyIndex(root, 1)
+	bn.notifyIndex(root, 1, 1)
 	if !bn.seenIndex[root][1] {
 		t.Errorf("Index was not marked as seen")
 	}
@@ -599,13 +610,13 @@ func TestNotifyIndex(t *testing.T) {
 	}

 	// Test notifying an already seen index
-	bn.notifyIndex(root, 1)
+	bn.notifyIndex(root, 1, 1)
 	if len(bn.notifiers[root]) > 1 {
 		t.Errorf("Notifier channel should not receive multiple messages for the same index")
 	}

 	// Test notifying a new index again
-	bn.notifyIndex(root, 2)
+	bn.notifyIndex(root, 2, 1)
 	if !bn.seenIndex[root][2] {
 		t.Errorf("Index was not marked as seen")
 	}
--- a/beacon-chain/blockchain/setup_test.go
+++ b/beacon-chain/blockchain/setup_test.go
@@ -19,8 +19,10 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/attestations"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/blstoexec"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/p2p"
+	p2pTesting "github.com/prysmaticlabs/prysm/v5/beacon-chain/p2p/testing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/startup"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state/stategen"
+	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/testing/require"
 	"google.golang.org/protobuf/proto"
@@ -32,7 +34,7 @@ type mockBeaconNode struct {
 }

 // StateFeed mocks the same method in the beacon node.
-func (mbn *mockBeaconNode) StateFeed() *event.Feed {
+func (mbn *mockBeaconNode) StateFeed() event.SubscriberSender {
 	mbn.mu.Lock()
 	defer mbn.mu.Unlock()
 	if mbn.stateFeed == nil {
@@ -45,6 +47,11 @@ type mockBroadcaster struct {
 	broadcastCalled bool
 }

+type mockAccesser struct {
+	mockBroadcaster
+	p2pTesting.MockPeerManager
+}
+
 func (mb *mockBroadcaster) Broadcast(_ context.Context, _ proto.Message) error {
 	mb.broadcastCalled = true
 	return nil
@@ -65,6 +72,11 @@ func (mb *mockBroadcaster) BroadcastBlob(_ context.Context, _ uint64, _ *ethpb.B
 	return nil
 }

+func (mb *mockBroadcaster) BroadcastDataColumn(_ context.Context, _ [fieldparams.RootLength]byte, _ uint64, _ *ethpb.DataColumnSidecar) error {
+	mb.broadcastCalled = true
+	return nil
+}
+
 func (mb *mockBroadcaster) BroadcastBLSChanges(_ context.Context, _ []*ethpb.SignedBLSToExecutionChange) {
 }

@@ -122,6 +134,7 @@ func minimalTestService(t *testing.T, opts ...Option) (*Service, *testServiceReq
 		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)),
 		WithSyncChecker(mock.MockChecker{}),
 		WithExecutionEngineCaller(&mockExecution.EngineClient{}),
+		WithP2PBroadcaster(&mockAccesser{}),
 	}
 	// append the variadic opts so they override the defaults by being processed afterwards
 	opts = append(defOpts, opts...)
--- a/beacon-chain/blockchain/testing/mock.go
+++ b/beacon-chain/blockchain/testing/mock.go
@@ -98,6 +98,44 @@ func (s *ChainService) BlockNotifier() blockfeed.Notifier {
 	return s.blockNotifier
 }

+type EventFeedWrapper struct {
+	feed       *event.Feed
+	subscribed chan struct{} // this channel is closed once a subscription is made
+}
+
+func (w *EventFeedWrapper) Subscribe(channel interface{}) event.Subscription {
+	select {
+	case <-w.subscribed:
+		break // already closed
+	default:
+		close(w.subscribed)
+	}
+	return w.feed.Subscribe(channel)
+}
+
+func (w *EventFeedWrapper) Send(value interface{}) int {
+	return w.feed.Send(value)
+}
+
+// WaitForSubscription allows test to wait for the feed to have a subscription before beginning to send events.
+func (w *EventFeedWrapper) WaitForSubscription(ctx context.Context) error {
+	select {
+	case <-w.subscribed:
+		return nil
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+}
+
+var _ event.SubscriberSender = &EventFeedWrapper{}
+
+func NewEventFeedWrapper() *EventFeedWrapper {
+	return &EventFeedWrapper{
+		feed:       new(event.Feed),
+		subscribed: make(chan struct{}),
+	}
+}
+
 // MockBlockNotifier mocks the block notifier.
 type MockBlockNotifier struct {
 	feed *event.Feed
@@ -131,7 +169,7 @@ func (msn *MockStateNotifier) ReceivedEvents() []*feed.Event {
 }

 // StateFeed returns a state feed.
-func (msn *MockStateNotifier) StateFeed() *event.Feed {
+func (msn *MockStateNotifier) StateFeed() event.SubscriberSender {
 	msn.feedLock.Lock()
 	defer msn.feedLock.Unlock()

@@ -159,6 +197,23 @@ func (msn *MockStateNotifier) StateFeed() *event.Feed {
 	return msn.feed
 }

+// NewSimpleStateNotifier makes a state feed without the custom mock feed machinery.
+func NewSimpleStateNotifier() *MockStateNotifier {
+	return &MockStateNotifier{feed: new(event.Feed)}
+}
+
+type SimpleNotifier struct {
+	Feed event.SubscriberSender
+}
+
+func (n *SimpleNotifier) StateFeed() event.SubscriberSender {
+	return n.Feed
+}
+
+func (n *SimpleNotifier) OperationFeed() event.SubscriberSender {
+	return n.Feed
+}
+
 // OperationNotifier mocks the same method in the chain service.
 func (s *ChainService) OperationNotifier() opfeed.Notifier {
 	if s.opNotifier == nil {
@@ -173,7 +228,7 @@ type MockOperationNotifier struct {
 }

 // OperationFeed returns an operation feed.
-func (mon *MockOperationNotifier) OperationFeed() *event.Feed {
+func (mon *MockOperationNotifier) OperationFeed() event.SubscriberSender {
 	if mon.feed == nil {
 		mon.feed = new(event.Feed)
 	}
@@ -512,7 +567,7 @@ func prepareForkchoiceState(
 	payloadHash [32]byte,
 	justified *ethpb.Checkpoint,
 	finalized *ethpb.Checkpoint,
-) (state.BeaconState, [32]byte, error) {
+) (state.BeaconState, blocks.ROBlock, error) {
 	blockHeader := &ethpb.BeaconBlockHeader{
 		ParentRoot: parentRoot[:],
 	}
@@ -533,7 +588,26 @@ func prepareForkchoiceState(

 	base.BlockRoots[0] = append(base.BlockRoots[0], blockRoot[:]...)
 	st, err := state_native.InitializeFromProtoBellatrix(base)
-	return st, blockRoot, err
+	if err != nil {
+		return nil, blocks.ROBlock{}, err
+	}
+	blk := &ethpb.SignedBeaconBlockBellatrix{
+		Block: &ethpb.BeaconBlockBellatrix{
+			Slot:       slot,
+			ParentRoot: parentRoot[:],
+			Body: &ethpb.BeaconBlockBodyBellatrix{
+				ExecutionPayload: &enginev1.ExecutionPayload{
+					BlockHash: payloadHash[:],
+				},
+			},
+		},
+	}
+	signed, err := blocks.NewSignedBeaconBlock(blk)
+	if err != nil {
+		return nil, blocks.ROBlock{}, err
+	}
+	roblock, err := blocks.NewROBlockWithRoot(signed, blockRoot)
+	return st, roblock, err
 }

 // CachedHeadRoot mocks the same method in the chain service
@@ -576,9 +650,9 @@ func (s *ChainService) HighestReceivedBlockSlot() primitives.Slot {
 }

 // InsertNode mocks the same method in the chain service
-func (s *ChainService) InsertNode(ctx context.Context, st state.BeaconState, root [32]byte) error {
+func (s *ChainService) InsertNode(ctx context.Context, st state.BeaconState, block blocks.ROBlock) error {
 	if s.ForkChoiceStore != nil {
-		return s.ForkChoiceStore.InsertNode(ctx, st, root)
+		return s.ForkChoiceStore.InsertNode(ctx, st, block)
 	}
 	return nil
 }
@@ -628,6 +702,11 @@ func (c *ChainService) ReceiveBlob(_ context.Context, b blocks.VerifiedROBlob) e
 	return nil
 }

+// ReceiveDataColumn implements the same method in chain service
+func (*ChainService) ReceiveDataColumn(_ blocks.VerifiedRODataColumn) error {
+	return nil
+}
+
 // TargetRootForEpoch mocks the same method in the chain service
 func (c *ChainService) TargetRootForEpoch(_ [32]byte, _ primitives.Epoch) ([32]byte, error) {
 	return c.TargetRoot, nil
--- a/beacon-chain/cache/BUILD.bazel
+++ b/beacon-chain/cache/BUILD.bazel
@@ -5,9 +5,11 @@ go_library(
    srcs = [
        "active_balance.go",
        "active_balance_disabled.go",  # keep
+        "attestation.go",
        "attestation_data.go",
        "balance_cache_key.go",
        "checkpoint_state.go",
+        "column_subnet_ids.go",
        "committee.go",
        "committee_disabled.go",  # keep
        "committees.go",
@@ -36,18 +38,21 @@ go_library(
    ],
    deps = [
        "//beacon-chain/forkchoice/types:go_default_library",
+        "//beacon-chain/operations/attestations/attmap:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//cache/lru:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//container/slice:go_default_library",
+        "//crypto/bls:go_default_library",
        "//crypto/hash:go_default_library",
        "//crypto/rand:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//math:go_default_library",
        "//monitoring/tracing/trace:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
+        "//proto/prysm/v1alpha1/attestation:go_default_library",
        "//runtime/version:go_default_library",
        "@com_github_ethereum_go_ethereum//common:go_default_library",
        "@com_github_hashicorp_golang_lru//:go_default_library",
@@ -66,6 +71,7 @@ go_test(
    srcs = [
        "active_balance_test.go",
        "attestation_data_test.go",
+        "attestation_test.go",
        "cache_test.go",
        "checkpoint_state_test.go",
        "committee_fuzz_test.go",
@@ -88,14 +94,17 @@ go_test(
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/primitives:go_default_library",
+        "//crypto/bls/blst:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
+        "//proto/prysm/v1alpha1/attestation:go_default_library",
        "//testing/assert:go_default_library",
        "//testing/require:go_default_library",
        "//testing/util:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
        "@com_github_google_gofuzz//:go_default_library",
        "@com_github_hashicorp_golang_lru//:go_default_library",
+        "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
        "@com_github_stretchr_testify//require:go_default_library",
        "@org_golang_google_protobuf//proto:go_default_library",
    ],
--- a/beacon-chain/cache/attestation.go
+++ b/beacon-chain/cache/attestation.go
@@ -0,0 +1,275 @@
+package cache
+
+import (
+	"sync"
+
+	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/attestations/attmap"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+	"github.com/prysmaticlabs/prysm/v5/crypto/bls"
+	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1/attestation"
+	log "github.com/sirupsen/logrus"
+)
+
+type attGroup struct {
+	slot primitives.Slot
+	atts []ethpb.Att
+}
+
+// AttestationCache holds a map of attGroup items that group together all attestations for a single slot.
+// When we add an attestation to the cache by calling Add, we either create a new group with this attestation
+// (if this is the first attestation for some slot) or two things can happen:
+//
+//   - If the attestation is unaggregated, we add its attestation bit to attestation bits of the first
+//     attestation in the group.
+//   - If the attestation is aggregated, we append it to the group. There should be no redundancy
+//     in the list because we ignore redundant aggregates in gossip.
+//
+// The first bullet point above means that we keep one aggregate attestation to which we keep appending bits
+// as new single-bit attestations arrive. This means that at any point during seconds 0-4 of a slot
+// we will have only one attestation for this slot in the cache.
+//
+// NOTE: This design in principle can result in worse aggregates since we lose the ability to aggregate some
+// single bit attestations in case of overlaps with incoming aggregates.
+//
+// The cache also keeps forkchoice attestations in a separate struct. These attestations are used for
+// forkchoice-related operations.
+type AttestationCache struct {
+	atts map[attestation.Id]*attGroup
+	sync.RWMutex
+	forkchoiceAtts *attmap.Attestations
+}
+
+// NewAttestationCache creates a new cache instance.
+func NewAttestationCache() *AttestationCache {
+	return &AttestationCache{
+		atts:           make(map[attestation.Id]*attGroup),
+		forkchoiceAtts: attmap.New(),
+	}
+}
+
+// Add does one of two things:
+//
+//   - For unaggregated attestations, it adds the attestation bit to attestation bits of the running aggregate,
+//     which is the first aggregate for the slot.
+//   - For aggregated attestations, it appends the attestation to the existing list of attestations for the slot.
+func (c *AttestationCache) Add(att ethpb.Att) error {
+	if att.IsNil() {
+		log.Debug("Attempted to add a nil attestation to the attestation cache")
+		return nil
+	}
+	if len(att.GetAggregationBits().BitIndices()) == 0 {
+		log.Debug("Attempted to add an attestation with 0 bits set to the attestation cache")
+		return nil
+	}
+
+	c.Lock()
+	defer c.Unlock()
+
+	id, err := attestation.NewId(att, attestation.Data)
+	if err != nil {
+		return errors.Wrapf(err, "could not create attestation ID")
+	}
+
+	group := c.atts[id]
+	if group == nil {
+		group = &attGroup{
+			slot: att.GetData().Slot,
+			atts: []ethpb.Att{att},
+		}
+		c.atts[id] = group
+		return nil
+	}
+
+	if att.IsAggregated() {
+		group.atts = append(group.atts, att.Clone())
+		return nil
+	}
+
+	// This should never happen because we return early for a new group.
+	if len(group.atts) == 0 {
+		log.Error("Attestation group contains no attestations, skipping insertion")
+		return nil
+	}
+
+	a := group.atts[0]
+
+	// Indexing is safe because we have guarded against 0 bits set.
+	bit := att.GetAggregationBits().BitIndices()[0]
+	if a.GetAggregationBits().BitAt(uint64(bit)) {
+		return nil
+	}
+	sig, err := aggregateSig(a, att)
+	if err != nil {
+		return errors.Wrapf(err, "could not aggregate signatures")
+	}
+
+	a.GetAggregationBits().SetBitAt(uint64(bit), true)
+	a.SetSignature(sig)
+
+	return nil
+}
+
+// GetAll returns all attestations in the cache, excluding forkchoice attestations.
+func (c *AttestationCache) GetAll() []ethpb.Att {
+	c.RLock()
+	defer c.RUnlock()
+
+	var result []ethpb.Att
+	for _, group := range c.atts {
+		result = append(result, group.atts...)
+	}
+	return result
+}
+
+// Count returns the number of all attestations in the cache, excluding forkchoice attestations.
+func (c *AttestationCache) Count() int {
+	c.RLock()
+	defer c.RUnlock()
+
+	count := 0
+	for _, group := range c.atts {
+		count += len(group.atts)
+	}
+	return count
+}
+
+// DeleteCovered removes all attestations whose attestation bits are a proper subset of the passed-in attestation.
+func (c *AttestationCache) DeleteCovered(att ethpb.Att) error {
+	if att.IsNil() {
+		return nil
+	}
+
+	c.Lock()
+	defer c.Unlock()
+
+	id, err := attestation.NewId(att, attestation.Data)
+	if err != nil {
+		return errors.Wrapf(err, "could not create attestation ID")
+	}
+
+	group := c.atts[id]
+	if group == nil {
+		return nil
+	}
+
+	idx := 0
+	for _, a := range group.atts {
+		if covered, err := att.GetAggregationBits().Contains(a.GetAggregationBits()); err != nil {
+			return err
+		} else if !covered {
+			group.atts[idx] = a
+			idx++
+		}
+	}
+	group.atts = group.atts[:idx]
+
+	if len(group.atts) == 0 {
+		delete(c.atts, id)
+	}
+
+	return nil
+}
+
+// PruneBefore removes all attestations whose slot is earlier than the passed-in slot.
+func (c *AttestationCache) PruneBefore(slot primitives.Slot) uint64 {
+	c.Lock()
+	defer c.Unlock()
+
+	var pruneCount int
+	for id, group := range c.atts {
+		if group.slot < slot {
+			pruneCount += len(group.atts)
+			delete(c.atts, id)
+		}
+	}
+	return uint64(pruneCount)
+}
+
+// AggregateIsRedundant checks whether all attestation bits of the passed-in aggregate
+// are already included by any aggregate in the cache.
+func (c *AttestationCache) AggregateIsRedundant(att ethpb.Att) (bool, error) {
+	if att.IsNil() {
+		return true, nil
+	}
+
+	c.RLock()
+	defer c.RUnlock()
+
+	id, err := attestation.NewId(att, attestation.Data)
+	if err != nil {
+		return true, errors.Wrapf(err, "could not create attestation ID")
+	}
+
+	group := c.atts[id]
+	if group == nil {
+		return false, nil
+	}
+
+	for _, a := range group.atts {
+		if redundant, err := a.GetAggregationBits().Contains(att.GetAggregationBits()); err != nil {
+			return true, err
+		} else if redundant {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
+// SaveForkchoiceAttestations saves forkchoice attestations.
+func (c *AttestationCache) SaveForkchoiceAttestations(att []ethpb.Att) error {
+	return c.forkchoiceAtts.SaveMany(att)
+}
+
+// ForkchoiceAttestations returns all forkchoice attestations.
+func (c *AttestationCache) ForkchoiceAttestations() []ethpb.Att {
+	return c.forkchoiceAtts.GetAll()
+}
+
+// DeleteForkchoiceAttestation deletes a forkchoice attestation.
+func (c *AttestationCache) DeleteForkchoiceAttestation(att ethpb.Att) error {
+	return c.forkchoiceAtts.Delete(att)
+}
+
+// GetBySlotAndCommitteeIndex returns all attestations in the cache that match the provided slot
+// and committee index. Forkchoice attestations are not returned.
+//
+// NOTE: This function cannot be declared as a method on the AttestationCache because it is a generic function.
+func GetBySlotAndCommitteeIndex[T ethpb.Att](c *AttestationCache, slot primitives.Slot, committeeIndex primitives.CommitteeIndex) []T {
+	c.RLock()
+	defer c.RUnlock()
+
+	var result []T
+
+	for _, group := range c.atts {
+		if len(group.atts) > 0 {
+			// We can safely compare the first attestation because all attestations in a group
+			// must have the same slot and committee index, since they are under the same key.
+			a, ok := group.atts[0].(T)
+			if ok && a.GetData().Slot == slot && a.CommitteeBitsVal().BitAt(uint64(committeeIndex)) {
+				for _, a := range group.atts {
+					a, ok := a.(T)
+					if ok {
+						result = append(result, a)
+					}
+				}
+			}
+		}
+	}
+
+	return result
+}
+
+func aggregateSig(agg ethpb.Att, att ethpb.Att) ([]byte, error) {
+	aggSig, err := bls.SignatureFromBytesNoValidation(agg.GetSignature())
+	if err != nil {
+		return nil, err
+	}
+	attSig, err := bls.SignatureFromBytesNoValidation(att.GetSignature())
+	if err != nil {
+		return nil, err
+	}
+	return bls.AggregateSignatures([]bls.Signature{aggSig, attSig}).Marshal(), nil
+}
--- a/beacon-chain/cache/attestation_data.go
+++ b/beacon-chain/cache/attestation_data.go
@@ -15,24 +15,24 @@ type AttestationConsensusData struct {
 	Source   forkchoicetypes.Checkpoint
 }

-// AttestationCache stores cached results of AttestationData requests.
-type AttestationCache struct {
+// AttestationDataCache stores cached results of AttestationData requests.
+type AttestationDataCache struct {
 	a *AttestationConsensusData
 	sync.RWMutex
 }

-// NewAttestationCache creates a new instance of AttestationCache.
-func NewAttestationCache() *AttestationCache {
-	return &AttestationCache{}
+// NewAttestationDataCache creates a new instance of AttestationDataCache.
+func NewAttestationDataCache() *AttestationDataCache {
+	return &AttestationDataCache{}
 }

 // Get retrieves cached attestation data, recording a cache hit or miss. This method is lock free.
-func (c *AttestationCache) Get() *AttestationConsensusData {
+func (c *AttestationDataCache) Get() *AttestationConsensusData {
 	return c.a
 }

 // Put adds a response to the cache. This method is lock free.
-func (c *AttestationCache) Put(a *AttestationConsensusData) error {
+func (c *AttestationDataCache) Put(a *AttestationConsensusData) error {
 	if a == nil {
 		return errors.New("attestation cannot be nil")
 	}
--- a/beacon-chain/cache/attestation_data_test.go
+++ b/beacon-chain/cache/attestation_data_test.go
@@ -9,7 +9,7 @@ import (
 )

 func TestAttestationCache_RoundTrip(t *testing.T) {
-	c := cache.NewAttestationCache()
+	c := cache.NewAttestationDataCache()

 	a := c.Get()
 	require.Nil(t, a)
--- a/beacon-chain/cache/attestation_test.go
+++ b/beacon-chain/cache/attestation_test.go
@@ -0,0 +1,353 @@
+package cache
+
+import (
+	"testing"
+
+	"github.com/prysmaticlabs/go-bitfield"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+	"github.com/prysmaticlabs/prysm/v5/crypto/bls/blst"
+	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
+	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1/attestation"
+	"github.com/prysmaticlabs/prysm/v5/testing/assert"
+	"github.com/prysmaticlabs/prysm/v5/testing/require"
+)
+
+func TestAdd(t *testing.T) {
+	k, err := blst.RandKey()
+	require.NoError(t, err)
+	sig := k.Sign([]byte{'X'})
+
+	t.Run("new ID", func(t *testing.T) {
+		t.Run("first ID ever", func(t *testing.T) {
+			c := NewAttestationCache()
+			ab := bitfield.NewBitlist(8)
+			ab.SetBitAt(0, true)
+			att := &ethpb.Attestation{
+				Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+				AggregationBits: ab,
+				Signature:       sig.Marshal(),
+			}
+			id, err := attestation.NewId(att, attestation.Data)
+			require.NoError(t, err)
+			require.NoError(t, c.Add(att))
+
+			require.Equal(t, 1, len(c.atts))
+			group, ok := c.atts[id]
+			require.Equal(t, true, ok)
+			assert.Equal(t, primitives.Slot(123), group.slot)
+			require.Equal(t, 1, len(group.atts))
+			assert.DeepEqual(t, group.atts[0], att)
+		})
+		t.Run("other ID exists", func(t *testing.T) {
+			c := NewAttestationCache()
+			ab := bitfield.NewBitlist(8)
+			ab.SetBitAt(0, true)
+			existingAtt := &ethpb.Attestation{
+				Data:            &ethpb.AttestationData{BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+				AggregationBits: ab,
+				Signature:       sig.Marshal(),
+			}
+			existingId, err := attestation.NewId(existingAtt, attestation.Data)
+			require.NoError(t, err)
+			c.atts[existingId] = &attGroup{slot: existingAtt.Data.Slot, atts: []ethpb.Att{existingAtt}}
+
+			att := &ethpb.Attestation{
+				Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+				AggregationBits: ab,
+				Signature:       sig.Marshal(),
+			}
+			id, err := attestation.NewId(att, attestation.Data)
+			require.NoError(t, err)
+			require.NoError(t, c.Add(att))
+
+			require.Equal(t, 2, len(c.atts))
+			group, ok := c.atts[id]
+			require.Equal(t, true, ok)
+			assert.Equal(t, primitives.Slot(123), group.slot)
+			require.Equal(t, 1, len(group.atts))
+			assert.DeepEqual(t, group.atts[0], att)
+		})
+	})
+	t.Run("aggregated", func(t *testing.T) {
+		c := NewAttestationCache()
+		existingAtt := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		id, err := attestation.NewId(existingAtt, attestation.Data)
+		require.NoError(t, err)
+		c.atts[id] = &attGroup{slot: existingAtt.Data.Slot, atts: []ethpb.Att{existingAtt}}
+
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+		att.AggregationBits.SetBitAt(1, true)
+		require.NoError(t, c.Add(att))
+
+		require.Equal(t, 1, len(c.atts))
+		group, ok := c.atts[id]
+		require.Equal(t, true, ok)
+		assert.Equal(t, primitives.Slot(123), group.slot)
+		require.Equal(t, 2, len(group.atts))
+		assert.DeepEqual(t, group.atts[0], existingAtt)
+		assert.DeepEqual(t, group.atts[1], att)
+	})
+	t.Run("unaggregated - existing bit", func(t *testing.T) {
+		c := NewAttestationCache()
+		existingAtt := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		existingAtt.AggregationBits.SetBitAt(0, true)
+		id, err := attestation.NewId(existingAtt, attestation.Data)
+		require.NoError(t, err)
+		c.atts[id] = &attGroup{slot: existingAtt.Data.Slot, atts: []ethpb.Att{existingAtt}}
+
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+		require.NoError(t, c.Add(att))
+
+		require.Equal(t, 1, len(c.atts))
+		group, ok := c.atts[id]
+		require.Equal(t, true, ok)
+		assert.Equal(t, primitives.Slot(123), group.slot)
+		require.Equal(t, 1, len(group.atts))
+		assert.DeepEqual(t, []int{0}, group.atts[0].GetAggregationBits().BitIndices())
+	})
+	t.Run("unaggregated - new bit", func(t *testing.T) {
+		c := NewAttestationCache()
+		existingAtt := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		existingAtt.AggregationBits.SetBitAt(0, true)
+		id, err := attestation.NewId(existingAtt, attestation.Data)
+		require.NoError(t, err)
+		c.atts[id] = &attGroup{slot: existingAtt.Data.Slot, atts: []ethpb.Att{existingAtt}}
+
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(1, true)
+		require.NoError(t, c.Add(att))
+
+		require.Equal(t, 1, len(c.atts))
+		group, ok := c.atts[id]
+		require.Equal(t, true, ok)
+		assert.Equal(t, primitives.Slot(123), group.slot)
+		require.Equal(t, 1, len(group.atts))
+		assert.DeepEqual(t, []int{0, 1}, group.atts[0].GetAggregationBits().BitIndices())
+	})
+}
+
+func TestGetAll(t *testing.T) {
+	c := NewAttestationCache()
+	c.atts[bytesutil.ToBytes32([]byte("id1"))] = &attGroup{atts: []ethpb.Att{&ethpb.Attestation{}, &ethpb.Attestation{}}}
+	c.atts[bytesutil.ToBytes32([]byte("id2"))] = &attGroup{atts: []ethpb.Att{&ethpb.Attestation{}}}
+
+	assert.Equal(t, 3, len(c.GetAll()))
+}
+
+func TestCount(t *testing.T) {
+	c := NewAttestationCache()
+	c.atts[bytesutil.ToBytes32([]byte("id1"))] = &attGroup{atts: []ethpb.Att{&ethpb.Attestation{}, &ethpb.Attestation{}}}
+	c.atts[bytesutil.ToBytes32([]byte("id2"))] = &attGroup{atts: []ethpb.Att{&ethpb.Attestation{}}}
+
+	assert.Equal(t, 3, c.Count())
+}
+
+func TestDeleteCovered(t *testing.T) {
+	k, err := blst.RandKey()
+	require.NoError(t, err)
+	sig := k.Sign([]byte{'X'})
+
+	att1 := &ethpb.Attestation{
+		Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+		AggregationBits: bitfield.NewBitlist(8),
+		Signature:       sig.Marshal(),
+	}
+	att1.AggregationBits.SetBitAt(0, true)
+
+	att2 := &ethpb.Attestation{
+		Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+		AggregationBits: bitfield.NewBitlist(8),
+		Signature:       sig.Marshal(),
+	}
+	att2.AggregationBits.SetBitAt(1, true)
+	att2.AggregationBits.SetBitAt(2, true)
+
+	att3 := &ethpb.Attestation{
+		Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+		AggregationBits: bitfield.NewBitlist(8),
+		Signature:       sig.Marshal(),
+	}
+	att3.AggregationBits.SetBitAt(1, true)
+	att3.AggregationBits.SetBitAt(3, true)
+	att3.AggregationBits.SetBitAt(4, true)
+
+	c := NewAttestationCache()
+	id, err := attestation.NewId(att1, attestation.Data)
+	require.NoError(t, err)
+	c.atts[id] = &attGroup{slot: att1.Data.Slot, atts: []ethpb.Att{att1, att2, att3}}
+
+	t.Run("no matching group", func(t *testing.T) {
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 456, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+		att.AggregationBits.SetBitAt(1, true)
+		att.AggregationBits.SetBitAt(2, true)
+		att.AggregationBits.SetBitAt(3, true)
+		att.AggregationBits.SetBitAt(4, true)
+		require.NoError(t, c.DeleteCovered(att))
+
+		assert.Equal(t, 3, len(c.atts[id].atts))
+	})
+	t.Run("covered atts deleted", func(t *testing.T) {
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+		att.AggregationBits.SetBitAt(1, true)
+		att.AggregationBits.SetBitAt(3, true)
+		att.AggregationBits.SetBitAt(4, true)
+		require.NoError(t, c.DeleteCovered(att))
+
+		atts := c.atts[id].atts
+		require.Equal(t, 1, len(atts))
+		assert.DeepEqual(t, att2, atts[0])
+	})
+	t.Run("last att in group deleted", func(t *testing.T) {
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+		att.AggregationBits.SetBitAt(1, true)
+		att.AggregationBits.SetBitAt(2, true)
+		att.AggregationBits.SetBitAt(3, true)
+		att.AggregationBits.SetBitAt(4, true)
+		require.NoError(t, c.DeleteCovered(att))
+
+		assert.Equal(t, 0, len(c.atts))
+	})
+}
+
+func TestPruneBefore(t *testing.T) {
+	c := NewAttestationCache()
+	c.atts[bytesutil.ToBytes32([]byte("id1"))] = &attGroup{slot: 1, atts: []ethpb.Att{&ethpb.Attestation{}, &ethpb.Attestation{}}}
+	c.atts[bytesutil.ToBytes32([]byte("id2"))] = &attGroup{slot: 3, atts: []ethpb.Att{&ethpb.Attestation{}}}
+	c.atts[bytesutil.ToBytes32([]byte("id3"))] = &attGroup{slot: 2, atts: []ethpb.Att{&ethpb.Attestation{}}}
+
+	count := c.PruneBefore(3)
+
+	require.Equal(t, 1, len(c.atts))
+	_, ok := c.atts[bytesutil.ToBytes32([]byte("id2"))]
+	assert.Equal(t, true, ok)
+	assert.Equal(t, uint64(3), count)
+}
+
+func TestAggregateIsRedundant(t *testing.T) {
+	k, err := blst.RandKey()
+	require.NoError(t, err)
+	sig := k.Sign([]byte{'X'})
+
+	c := NewAttestationCache()
+	existingAtt := &ethpb.Attestation{
+		Data:            &ethpb.AttestationData{Slot: 123, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+		AggregationBits: bitfield.NewBitlist(8),
+		Signature:       sig.Marshal(),
+	}
+	existingAtt.AggregationBits.SetBitAt(0, true)
+	existingAtt.AggregationBits.SetBitAt(1, true)
+	id, err := attestation.NewId(existingAtt, attestation.Data)
+	require.NoError(t, err)
+	c.atts[id] = &attGroup{slot: existingAtt.Data.Slot, atts: []ethpb.Att{existingAtt}}
+
+	t.Run("no matching group", func(t *testing.T) {
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: 456, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+
+		redundant, err := c.AggregateIsRedundant(att)
+		require.NoError(t, err)
+		assert.Equal(t, false, redundant)
+	})
+	t.Run("redundant", func(t *testing.T) {
+		att := &ethpb.Attestation{
+			Data:            &ethpb.AttestationData{Slot: existingAtt.Data.Slot, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+			AggregationBits: bitfield.NewBitlist(8),
+			Signature:       sig.Marshal(),
+		}
+		att.AggregationBits.SetBitAt(0, true)
+
+		redundant, err := c.AggregateIsRedundant(att)
+		require.NoError(t, err)
+		assert.Equal(t, true, redundant)
+	})
+	t.Run("not redundant", func(t *testing.T) {
+		t.Run("strictly better", func(t *testing.T) {
+			att := &ethpb.Attestation{
+				Data:            &ethpb.AttestationData{Slot: existingAtt.Data.Slot, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+				AggregationBits: bitfield.NewBitlist(8),
+				Signature:       sig.Marshal(),
+			}
+			att.AggregationBits.SetBitAt(0, true)
+			att.AggregationBits.SetBitAt(1, true)
+			att.AggregationBits.SetBitAt(2, true)
+
+			redundant, err := c.AggregateIsRedundant(att)
+			require.NoError(t, err)
+			assert.Equal(t, false, redundant)
+		})
+		t.Run("overlapping and new bits", func(t *testing.T) {
+			att := &ethpb.Attestation{
+				Data:            &ethpb.AttestationData{Slot: existingAtt.Data.Slot, BeaconBlockRoot: make([]byte, 32), Source: &ethpb.Checkpoint{Root: make([]byte, 32)}, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}},
+				AggregationBits: bitfield.NewBitlist(8),
+				Signature:       sig.Marshal(),
+			}
+			att.AggregationBits.SetBitAt(0, true)
+			att.AggregationBits.SetBitAt(2, true)
+
+			redundant, err := c.AggregateIsRedundant(att)
+			require.NoError(t, err)
+			assert.Equal(t, false, redundant)
+		})
+	})
+}
+
+func TestGetBySlotAndCommitteeIndex(t *testing.T) {
+	c := NewAttestationCache()
+	c.atts[bytesutil.ToBytes32([]byte("id1"))] = &attGroup{slot: 1, atts: []ethpb.Att{&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 1, CommitteeIndex: 1}}, &ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 1, CommitteeIndex: 1}}}}
+	c.atts[bytesutil.ToBytes32([]byte("id2"))] = &attGroup{slot: 2, atts: []ethpb.Att{&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 2, CommitteeIndex: 2}}}}
+	c.atts[bytesutil.ToBytes32([]byte("id3"))] = &attGroup{slot: 1, atts: []ethpb.Att{&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 2, CommitteeIndex: 2}}}}
+
+	// committeeIndex has to be small enough to fit in the bitvector
+	atts := GetBySlotAndCommitteeIndex[*ethpb.Attestation](c, 1, 1)
+	require.Equal(t, 2, len(atts))
+	assert.Equal(t, primitives.Slot(1), atts[0].Data.Slot)
+	assert.Equal(t, primitives.Slot(1), atts[1].Data.Slot)
+	assert.Equal(t, primitives.CommitteeIndex(1), atts[0].Data.CommitteeIndex)
+	assert.Equal(t, primitives.CommitteeIndex(1), atts[1].Data.CommitteeIndex)
+}
--- a/beacon-chain/cache/column_subnet_ids.go
+++ b/beacon-chain/cache/column_subnet_ids.go
@@ -0,0 +1,70 @@
+package cache
+
+import (
+	"sync"
+	"time"
+
+	"github.com/patrickmn/go-cache"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
+)
+
+type columnSubnetIDs struct {
+	colSubCache *cache.Cache
+	colSubLock  sync.RWMutex
+}
+
+// ColumnSubnetIDs for column subnet participants
+var ColumnSubnetIDs = newColumnSubnetIDs()
+
+const columnKey = "columns"
+
+func newColumnSubnetIDs() *columnSubnetIDs {
+	secondsPerSlot := params.BeaconConfig().SecondsPerSlot
+	slotsPerEpoch := params.BeaconConfig().SlotsPerEpoch
+	epochDuration := time.Duration(slotsPerEpoch.Mul(secondsPerSlot))
+
+	// Set the default duration of a column subnet subscription as the column expiry period.
+	minEpochsForDataColumnSidecarsRequest := time.Duration(params.BeaconConfig().MinEpochsForDataColumnSidecarsRequest)
+	subLength := epochDuration * minEpochsForDataColumnSidecarsRequest
+
+	persistentCache := cache.New(subLength*time.Second, epochDuration*time.Second)
+	return &columnSubnetIDs{colSubCache: persistentCache}
+}
+
+// GetColumnSubnets retrieves the data column subnets.
+func (s *columnSubnetIDs) GetColumnSubnets() ([]uint64, bool, time.Time) {
+	s.colSubLock.RLock()
+	defer s.colSubLock.RUnlock()
+
+	id, duration, ok := s.colSubCache.GetWithExpiration(columnKey)
+	if !ok {
+		return nil, false, time.Time{}
+	}
+	// Retrieve indices from the cache.
+	idxs, ok := id.([]uint64)
+	if !ok {
+		return nil, false, time.Time{}
+	}
+
+	return idxs, ok, duration
+}
+
+// AddColumnSubnets adds the relevant data column subnets.
+func (s *columnSubnetIDs) AddColumnSubnets(colIdx []uint64) {
+	s.colSubLock.Lock()
+	defer s.colSubLock.Unlock()
+
+	s.colSubCache.Set(columnKey, colIdx, 0)
+}
+
+// EmptyAllCaches empties out all the related caches and flushes any stored
+// entries on them. This should only ever be used for testing, in normal
+// production, handling of the relevant subnets for each role is done
+// separately.
+func (s *columnSubnetIDs) EmptyAllCaches() {
+	// Clear the cache.
+	s.colSubLock.Lock()
+	defer s.colSubLock.Unlock()
+
+	s.colSubCache.Flush()
+}
--- a/beacon-chain/core/altair/deposit.go
+++ b/beacon-chain/core/altair/deposit.go
@@ -37,7 +37,7 @@ func ProcessDeposits(
 	beaconState state.BeaconState,
 	deposits []*ethpb.Deposit,
 ) (state.BeaconState, error) {
-	batchVerified, err := blocks.BatchVerifyDepositsSignatures(ctx, deposits)
+	allSignaturesVerified, err := blocks.BatchVerifyDepositsSignatures(ctx, deposits)
 	if err != nil {
 		return nil, err
 	}
@@ -46,7 +46,7 @@ func ProcessDeposits(
 		if deposit == nil || deposit.Data == nil {
 			return nil, errors.New("got a nil deposit in block")
 		}
-		beaconState, err = ProcessDeposit(beaconState, deposit, batchVerified)
+		beaconState, err = ProcessDeposit(beaconState, deposit, allSignaturesVerified)
 		if err != nil {
 			return nil, errors.Wrapf(err, "could not process deposit from %#x", bytesutil.Trunc(deposit.Data.PublicKey))
 		}
@@ -81,7 +81,7 @@ func ProcessDeposits(
 //	  amount=deposit.data.amount,
 //	  signature=deposit.data.signature,
 //	 )
-func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verifySignature bool) (state.BeaconState, error) {
+func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, allSignaturesVerified bool) (state.BeaconState, error) {
 	if err := blocks.VerifyDeposit(beaconState, deposit); err != nil {
 		if deposit == nil || deposit.Data == nil {
 			return nil, err
@@ -92,7 +92,7 @@ func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verif
 		return nil, err
 	}

-	return ApplyDeposit(beaconState, deposit.Data, verifySignature)
+	return ApplyDeposit(beaconState, deposit.Data, allSignaturesVerified)
 }

 // ApplyDeposit
@@ -115,13 +115,13 @@ func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verif
 //	    # Increase balance by deposit amount
 //	    index = ValidatorIndex(validator_pubkeys.index(pubkey))
 //	    increase_balance(state, index, amount)
-func ApplyDeposit(beaconState state.BeaconState, data *ethpb.Deposit_Data, verifySignature bool) (state.BeaconState, error) {
+func ApplyDeposit(beaconState state.BeaconState, data *ethpb.Deposit_Data, allSignaturesVerified bool) (state.BeaconState, error) {
 	pubKey := data.PublicKey
 	amount := data.Amount
 	withdrawalCredentials := data.WithdrawalCredentials
 	index, ok := beaconState.ValidatorIndexByPubkey(bytesutil.ToBytes48(pubKey))
 	if !ok {
-		if verifySignature {
+		if !allSignaturesVerified {
 			valid, err := blocks.IsValidDepositSignature(data)
 			if err != nil {
 				return nil, err
@@ -187,11 +187,12 @@ func AddValidatorToRegistry(beaconState state.BeaconState, pubKey []byte, withdr
 //	return Validator(
 //	    pubkey=pubkey,
 //	    withdrawal_credentials=withdrawal_credentials,
+//	    effective_balance=effective_balance,
+//	    slashed=False,
 //	    activation_eligibility_epoch=FAR_FUTURE_EPOCH,
 //	    activation_epoch=FAR_FUTURE_EPOCH,
 //	    exit_epoch=FAR_FUTURE_EPOCH,
 //	    withdrawable_epoch=FAR_FUTURE_EPOCH,
-//	    effective_balance=effective_balance,
 //	)
 func GetValidatorFromDeposit(pubKey []byte, withdrawalCredentials []byte, amount uint64) *ethpb.Validator {
 	effectiveBalance := amount - (amount % params.BeaconConfig().EffectiveBalanceIncrement)
@@ -202,10 +203,11 @@ func GetValidatorFromDeposit(pubKey []byte, withdrawalCredentials []byte, amount
 	return &ethpb.Validator{
 		PublicKey:                  pubKey,
 		WithdrawalCredentials:      withdrawalCredentials,
+		EffectiveBalance:           effectiveBalance,
+		Slashed:                    false,
 		ActivationEligibilityEpoch: params.BeaconConfig().FarFutureEpoch,
 		ActivationEpoch:            params.BeaconConfig().FarFutureEpoch,
 		ExitEpoch:                  params.BeaconConfig().FarFutureEpoch,
 		WithdrawableEpoch:          params.BeaconConfig().FarFutureEpoch,
-		EffectiveBalance:           effectiveBalance,
 	}
 }
--- a/beacon-chain/core/altair/deposit_test.go
+++ b/beacon-chain/core/altair/deposit_test.go
@@ -199,7 +199,7 @@ func TestProcessDeposit_SkipsInvalidDeposit(t *testing.T) {
 		},
 	})
 	require.NoError(t, err)
-	newState, err := altair.ProcessDeposit(beaconState, dep[0], true)
+	newState, err := altair.ProcessDeposit(beaconState, dep[0], false)
 	require.NoError(t, err, "Expected invalid block deposit to be ignored without error")

 	if newState.Eth1DepositIndex() != 1 {
--- a/beacon-chain/core/altair/epoch_spec_test.go
+++ b/beacon-chain/core/altair/epoch_spec_test.go
@@ -105,10 +105,9 @@ func TestProcessSlashings_NotSlashed(t *testing.T) {
 	}
 	s, err := state_native.InitializeFromProtoAltair(base)
 	require.NoError(t, err)
-	newState, err := epoch.ProcessSlashings(s, params.BeaconConfig().ProportionalSlashingMultiplierAltair)
-	require.NoError(t, err)
+	require.NoError(t, epoch.ProcessSlashings(s))
 	wanted := params.BeaconConfig().MaxEffectiveBalance
-	assert.Equal(t, wanted, newState.Balances()[0], "Unexpected slashed balance")
+	assert.Equal(t, wanted, s.Balances()[0], "Unexpected slashed balance")
 }

 func TestProcessSlashings_SlashedLess(t *testing.T) {
@@ -176,9 +175,8 @@ func TestProcessSlashings_SlashedLess(t *testing.T) {
 			original := proto.Clone(tt.state)
 			s, err := state_native.InitializeFromProtoAltair(tt.state)
 			require.NoError(t, err)
-			newState, err := epoch.ProcessSlashings(s, params.BeaconConfig().ProportionalSlashingMultiplierAltair)
-			require.NoError(t, err)
-			assert.Equal(t, tt.want, newState.Balances()[0], "ProcessSlashings({%v}) = newState; newState.Balances[0] = %d", original, newState.Balances()[0])
+			require.NoError(t, epoch.ProcessSlashings(s))
+			assert.Equal(t, tt.want, s.Balances()[0], "ProcessSlashings({%v}) = newState; newState.Balances[0] = %d", original, s.Balances()[0])
 		})
 	}
 }
@@ -192,6 +190,5 @@ func TestProcessSlashings_BadValue(t *testing.T) {
 	}
 	s, err := state_native.InitializeFromProtoAltair(base)
 	require.NoError(t, err)
-	_, err = epoch.ProcessSlashings(s, params.BeaconConfig().ProportionalSlashingMultiplierAltair)
-	require.ErrorContains(t, "addition overflows", err)
+	require.ErrorContains(t, "addition overflows", epoch.ProcessSlashings(s))
 }
--- a/beacon-chain/core/altair/sync_committee.go
+++ b/beacon-chain/core/altair/sync_committee.go
@@ -2,6 +2,7 @@ package altair

 import (
 	"context"
+	"encoding/binary"
 	goErrors "errors"
 	"fmt"
 	"time"
@@ -22,8 +23,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )

-const maxRandomByte = uint64(1<<8 - 1)
-
 var (
 	ErrTooLate = errors.New("sync message is too late")
 )
@@ -91,19 +90,22 @@ func NextSyncCommittee(ctx context.Context, s state.BeaconState) (*ethpb.SyncCom
 //	"""
 //	epoch = Epoch(get_current_epoch(state) + 1)
 //
-//	MAX_RANDOM_BYTE = 2**8 - 1
+//	MAX_RANDOM_VALUE = 2**16 - 1  # [Modified in Electra]
 //	active_validator_indices = get_active_validator_indices(state, epoch)
 //	active_validator_count = uint64(len(active_validator_indices))
 //	seed = get_seed(state, epoch, DOMAIN_SYNC_COMMITTEE)
-//	i = 0
+//	i = uint64(0)
 //	sync_committee_indices: List[ValidatorIndex] = []
 //	while len(sync_committee_indices) < SYNC_COMMITTEE_SIZE:
 //	    shuffled_index = compute_shuffled_index(uint64(i % active_validator_count), active_validator_count, seed)
 //	    candidate_index = active_validator_indices[shuffled_index]
-//	    random_byte = hash(seed + uint_to_bytes(uint64(i // 32)))[i % 32]
+//	    # [Modified in Electra]
+//	    random_bytes = hash(seed + uint_to_bytes(i // 16))
+//	    offset = i % 16 * 2
+//	    random_value = bytes_to_uint64(random_bytes[offset:offset + 2])
 //	    effective_balance = state.validators[candidate_index].effective_balance
 //	    # [Modified in Electra:EIP7251]
-//	    if effective_balance * MAX_RANDOM_BYTE >= MAX_EFFECTIVE_BALANCE_ELECTRA * random_byte:
+//	    if effective_balance * MAX_RANDOM_VALUE >= MAX_EFFECTIVE_BALANCE_ELECTRA * random_value:
 //	        sync_committee_indices.append(candidate_index)
 //	    i += 1
 //	return sync_committee_indices
@@ -123,12 +125,11 @@ func NextSyncCommitteeIndices(ctx context.Context, s state.BeaconState) ([]primi
 	cIndices := make([]primitives.ValidatorIndex, 0, syncCommitteeSize)
 	hashFunc := hash.CustomSHA256Hasher()

-	maxEB := cfg.MaxEffectiveBalanceElectra
-	if s.Version() < version.Electra {
-		maxEB = cfg.MaxEffectiveBalance
-	}
+	// Preallocate buffers to avoid repeated allocations
+	seedBuffer := make([]byte, len(seed)+8)
+	copy(seedBuffer, seed[:])

-	for i := primitives.ValidatorIndex(0); uint64(len(cIndices)) < params.BeaconConfig().SyncCommitteeSize; i++ {
+	for i := primitives.ValidatorIndex(0); uint64(len(cIndices)) < syncCommitteeSize; i++ {
 		if ctx.Err() != nil {
 			return nil, ctx.Err()
 		}
@@ -137,18 +138,30 @@ func NextSyncCommitteeIndices(ctx context.Context, s state.BeaconState) ([]primi
 		if err != nil {
 			return nil, err
 		}
-
-		b := append(seed[:], bytesutil.Bytes8(uint64(i.Div(32)))...)
-		randomByte := hashFunc(b)[i%32]
 		cIndex := indices[sIndex]
 		v, err := s.ValidatorAtIndexReadOnly(cIndex)
 		if err != nil {
 			return nil, err
 		}
-
 		effectiveBal := v.EffectiveBalance()
-		if effectiveBal*maxRandomByte >= maxEB*uint64(randomByte) {
-			cIndices = append(cIndices, cIndex)
+
+		if s.Version() >= version.Electra {
+			// Use the preallocated seed buffer
+			binary.LittleEndian.PutUint64(seedBuffer[len(seed):], uint64(i/16))
+			randomByte := hashFunc(seedBuffer)
+			offset := (i % 16) * 2
+			randomValue := uint64(randomByte[offset]) | uint64(randomByte[offset+1])<<8
+
+			if effectiveBal*fieldparams.MaxRandomValueElectra >= cfg.MaxEffectiveBalanceElectra*randomValue {
+				cIndices = append(cIndices, cIndex)
+			}
+		} else {
+			// Use the preallocated seed buffer
+			binary.LittleEndian.PutUint64(seedBuffer[len(seed):], uint64(i/32))
+			randomByte := hashFunc(seedBuffer)[i%32]
+			if effectiveBal*fieldparams.MaxRandomByte >= cfg.MaxEffectiveBalance*uint64(randomByte) {
+				cIndices = append(cIndices, cIndex)
+			}
 		}
 	}

--- a/beacon-chain/core/altair/transition.go
+++ b/beacon-chain/core/altair/transition.go
@@ -69,12 +69,7 @@ func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
 	}

 	// Modified in Altair and Bellatrix.
-	proportionalSlashingMultiplier, err := state.ProportionalSlashingMultiplier()
-	if err != nil {
-		return err
-	}
-	state, err = e.ProcessSlashings(state, proportionalSlashingMultiplier)
-	if err != nil {
+	if err := e.ProcessSlashings(state); err != nil {
 		return err
 	}
 	state, err = e.ProcessEth1DataReset(state)
--- a/beacon-chain/core/blocks/attestation_test.go
+++ b/beacon-chain/core/blocks/attestation_test.go
@@ -448,6 +448,7 @@ func TestValidateIndexedAttestation_AboveMaxLength(t *testing.T) {
 			Target: &ethpb.Checkpoint{
 				Epoch: primitives.Epoch(i),
 			},
+			Source: &ethpb.Checkpoint{},
 		}
 	}

@@ -489,6 +490,7 @@ func TestValidateIndexedAttestation_BadAttestationsSignatureSet(t *testing.T) {
 				Target: &ethpb.Checkpoint{
 					Root: []byte{},
 				},
+				Source: &ethpb.Checkpoint{},
 			},
 			Signature:       sig.Marshal(),
 			AggregationBits: list,
--- a/beacon-chain/core/blocks/deposit.go
+++ b/beacon-chain/core/blocks/deposit.go
@@ -55,12 +55,26 @@ func BatchVerifyDepositsSignatures(ctx context.Context, deposits []*ethpb.Deposi
 		return false, err
 	}

-	verified := false
 	if err := verifyDepositDataWithDomain(ctx, deposits, domain); err != nil {
 		log.WithError(err).Debug("Failed to batch verify deposits signatures, will try individual verify")
-		verified = true
+		return false, nil
 	}
-	return verified, nil
+	return true, nil
+}
+
+// BatchVerifyPendingDepositsSignatures batch verifies pending deposit signatures.
+func BatchVerifyPendingDepositsSignatures(ctx context.Context, deposits []*ethpb.PendingDeposit) (bool, error) {
+	var err error
+	domain, err := signing.ComputeDomain(params.BeaconConfig().DomainDeposit, nil, nil)
+	if err != nil {
+		return false, err
+	}
+
+	if err := verifyPendingDepositDataWithDomain(ctx, deposits, domain); err != nil {
+		log.WithError(err).Debug("Failed to batch verify deposits signatures, will try individual verify")
+		return false, nil
+	}
+	return true, nil
 }

 // IsValidDepositSignature returns whether deposit_data is valid
@@ -159,3 +173,44 @@ func verifyDepositDataWithDomain(ctx context.Context, deps []*ethpb.Deposit, dom
 	}
 	return nil
 }
+
+func verifyPendingDepositDataWithDomain(ctx context.Context, deps []*ethpb.PendingDeposit, domain []byte) error {
+	if len(deps) == 0 {
+		return nil
+	}
+	pks := make([]bls.PublicKey, len(deps))
+	sigs := make([][]byte, len(deps))
+	msgs := make([][32]byte, len(deps))
+	for i, dep := range deps {
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+		if dep == nil {
+			return errors.New("nil deposit")
+		}
+		dpk, err := bls.PublicKeyFromBytes(dep.PublicKey)
+		if err != nil {
+			return err
+		}
+		pks[i] = dpk
+		sigs[i] = dep.Signature
+		depositMessage := &ethpb.DepositMessage{
+			PublicKey:             dep.PublicKey,
+			WithdrawalCredentials: dep.WithdrawalCredentials,
+			Amount:                dep.Amount,
+		}
+		sr, err := signing.ComputeSigningRoot(depositMessage, domain)
+		if err != nil {
+			return err
+		}
+		msgs[i] = sr
+	}
+	verify, err := bls.VerifyMultipleSignatures(sigs, msgs, pks)
+	if err != nil {
+		return errors.Errorf("could not verify multiple signatures: %v", err)
+	}
+	if !verify {
+		return errors.New("one or more deposit signatures did not verify")
+	}
+	return nil
+}
--- a/beacon-chain/core/blocks/deposit_test.go
+++ b/beacon-chain/core/blocks/deposit_test.go
@@ -17,6 +17,41 @@ import (
 )

 func TestBatchVerifyDepositsSignatures_Ok(t *testing.T) {
+	sk, err := bls.RandKey()
+	require.NoError(t, err)
+	domain, err := signing.ComputeDomain(params.BeaconConfig().DomainDeposit, nil, nil)
+	require.NoError(t, err)
+	deposit := &ethpb.Deposit{
+		Data: &ethpb.Deposit_Data{
+			PublicKey:             sk.PublicKey().Marshal(),
+			WithdrawalCredentials: make([]byte, 32),
+			Amount:                3000,
+		},
+	}
+	sr, err := signing.ComputeSigningRoot(&ethpb.DepositMessage{
+		PublicKey:             deposit.Data.PublicKey,
+		WithdrawalCredentials: deposit.Data.WithdrawalCredentials,
+		Amount:                3000,
+	}, domain)
+	require.NoError(t, err)
+	sig := sk.Sign(sr[:])
+	deposit.Data.Signature = sig.Marshal()
+	leaf, err := deposit.Data.HashTreeRoot()
+	require.NoError(t, err)
+	// We then create a merkle branch for the test.
+	depositTrie, err := trie.GenerateTrieFromItems([][]byte{leaf[:]}, params.BeaconConfig().DepositContractTreeDepth)
+	require.NoError(t, err, "Could not generate trie")
+	proof, err := depositTrie.MerkleProof(0)
+	require.NoError(t, err, "Could not generate proof")
+
+	deposit.Proof = proof
+	require.NoError(t, err)
+	verified, err := blocks.BatchVerifyDepositsSignatures(context.Background(), []*ethpb.Deposit{deposit})
+	require.NoError(t, err)
+	require.Equal(t, true, verified)
+}
+
+func TestBatchVerifyDepositsSignatures_InvalidSignature(t *testing.T) {
 	deposit := &ethpb.Deposit{
 		Data: &ethpb.Deposit_Data{
 			PublicKey:             bytesutil.PadTo([]byte{1, 2, 3}, 48),
@@ -34,9 +69,9 @@ func TestBatchVerifyDepositsSignatures_Ok(t *testing.T) {

 	deposit.Proof = proof
 	require.NoError(t, err)
-	ok, err := blocks.BatchVerifyDepositsSignatures(context.Background(), []*ethpb.Deposit{deposit})
+	verified, err := blocks.BatchVerifyDepositsSignatures(context.Background(), []*ethpb.Deposit{deposit})
 	require.NoError(t, err)
-	require.Equal(t, true, ok)
+	require.Equal(t, false, verified)
 }

 func TestVerifyDeposit_MerkleBranchFailsVerification(t *testing.T) {
@@ -93,3 +128,54 @@ func TestIsValidDepositSignature_Ok(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, true, valid)
 }
+
+func TestBatchVerifyPendingDepositsSignatures_Ok(t *testing.T) {
+	sk, err := bls.RandKey()
+	require.NoError(t, err)
+	domain, err := signing.ComputeDomain(params.BeaconConfig().DomainDeposit, nil, nil)
+	require.NoError(t, err)
+	pendingDeposit := &ethpb.PendingDeposit{
+		PublicKey:             sk.PublicKey().Marshal(),
+		WithdrawalCredentials: make([]byte, 32),
+		Amount:                3000,
+	}
+	sr, err := signing.ComputeSigningRoot(&ethpb.DepositMessage{
+		PublicKey:             pendingDeposit.PublicKey,
+		WithdrawalCredentials: pendingDeposit.WithdrawalCredentials,
+		Amount:                3000,
+	}, domain)
+	require.NoError(t, err)
+	sig := sk.Sign(sr[:])
+	pendingDeposit.Signature = sig.Marshal()
+
+	sk2, err := bls.RandKey()
+	require.NoError(t, err)
+	pendingDeposit2 := &ethpb.PendingDeposit{
+		PublicKey:             sk2.PublicKey().Marshal(),
+		WithdrawalCredentials: make([]byte, 32),
+		Amount:                4000,
+	}
+	sr2, err := signing.ComputeSigningRoot(&ethpb.DepositMessage{
+		PublicKey:             pendingDeposit2.PublicKey,
+		WithdrawalCredentials: pendingDeposit2.WithdrawalCredentials,
+		Amount:                4000,
+	}, domain)
+	require.NoError(t, err)
+	sig2 := sk2.Sign(sr2[:])
+	pendingDeposit2.Signature = sig2.Marshal()
+
+	verified, err := blocks.BatchVerifyPendingDepositsSignatures(context.Background(), []*ethpb.PendingDeposit{pendingDeposit, pendingDeposit2})
+	require.NoError(t, err)
+	require.Equal(t, true, verified)
+}
+
+func TestBatchVerifyPendingDepositsSignatures_InvalidSignature(t *testing.T) {
+	pendingDeposit := &ethpb.PendingDeposit{
+		PublicKey:             bytesutil.PadTo([]byte{1, 2, 3}, 48),
+		WithdrawalCredentials: make([]byte, 32),
+		Signature:             make([]byte, 96),
+	}
+	verified, err := blocks.BatchVerifyPendingDepositsSignatures(context.Background(), []*ethpb.PendingDeposit{pendingDeposit})
+	require.NoError(t, err)
+	require.Equal(t, false, verified)
+}
--- a/beacon-chain/core/blocks/exports_test.go
+++ b/beacon-chain/core/blocks/exports_test.go
@@ -1,5 +1,5 @@
 package blocks

 var ProcessBLSToExecutionChange = processBLSToExecutionChange
-
+var ErrInvalidBLSPrefix = errInvalidBLSPrefix
 var VerifyBlobCommitmentCount = verifyBlobCommitmentCount
--- a/beacon-chain/core/blocks/genesis.go
+++ b/beacon-chain/core/blocks/genesis.go
@@ -198,7 +198,7 @@ func NewGenesisBlockForState(ctx context.Context, st state.BeaconState) (interfa
 						SyncCommitteeBits:      make([]byte, fieldparams.SyncCommitteeLength/8),
 						SyncCommitteeSignature: make([]byte, fieldparams.BLSSignatureLength),
 					},
-					ExecutionPayload: &enginev1.ExecutionPayloadElectra{
+					ExecutionPayload: &enginev1.ExecutionPayloadDeneb{
 						ParentHash:    make([]byte, 32),
 						FeeRecipient:  make([]byte, 20),
 						StateRoot:     make([]byte, 32),
@@ -213,6 +213,11 @@ func NewGenesisBlockForState(ctx context.Context, st state.BeaconState) (interfa
 					},
 					BlsToExecutionChanges: make([]*ethpb.SignedBLSToExecutionChange, 0),
 					BlobKzgCommitments:    make([][]byte, 0),
+					ExecutionRequests: &enginev1.ExecutionRequests{
+						Withdrawals:    make([]*enginev1.WithdrawalRequest, 0),
+						Deposits:       make([]*enginev1.DepositRequest, 0),
+						Consolidations: make([]*enginev1.ConsolidationRequest, 0),
+					},
 				},
 			},
 			Signature: params.BeaconConfig().EmptySignature[:],
--- a/beacon-chain/core/blocks/payload.go
+++ b/beacon-chain/core/blocks/payload.go
@@ -8,10 +8,11 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	field_params "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
 	consensus_types "github.com/prysmaticlabs/prysm/v5/consensus-types"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
@@ -61,6 +62,9 @@ func IsExecutionBlock(body interfaces.ReadOnlyBeaconBlockBody) (bool, error) {
 	if body == nil {
 		return false, errors.New("nil block body")
 	}
+	if body.Version() >= version.Capella {
+		return true, nil
+	}
 	payload, err := body.Execution()
 	switch {
 	case errors.Is(err, consensus_types.ErrUnsupportedField):
@@ -202,27 +206,27 @@ func ValidatePayload(st state.BeaconState, payload interfaces.ExecutionData) err
 //	    block_hash=payload.block_hash,
 //	    transactions_root=hash_tree_root(payload.transactions),
 //	)
-func ProcessPayload(st state.BeaconState, body interfaces.ReadOnlyBeaconBlockBody) (state.BeaconState, error) {
+func ProcessPayload(st state.BeaconState, body interfaces.ReadOnlyBeaconBlockBody) error {
 	payload, err := body.Execution()
 	if err != nil {
-		return nil, err
+		return err
 	}
-	if err := verifyBlobCommitmentCount(body); err != nil {
-		return nil, err
+	if err := verifyBlobCommitmentCount(st.Slot(), body); err != nil {
+		return err
 	}
 	if err := ValidatePayloadWhenMergeCompletes(st, payload); err != nil {
-		return nil, err
+		return err
 	}
 	if err := ValidatePayload(st, payload); err != nil {
-		return nil, err
+		return err
 	}
 	if err := st.SetLatestExecutionPayloadHeader(payload); err != nil {
-		return nil, err
+		return err
 	}
-	return st, nil
+	return nil
 }

-func verifyBlobCommitmentCount(body interfaces.ReadOnlyBeaconBlockBody) error {
+func verifyBlobCommitmentCount(slot primitives.Slot, body interfaces.ReadOnlyBeaconBlockBody) error {
 	if body.Version() < version.Deneb {
 		return nil
 	}
@@ -230,7 +234,8 @@ func verifyBlobCommitmentCount(body interfaces.ReadOnlyBeaconBlockBody) error {
 	if err != nil {
 		return err
 	}
-	if len(kzgs) > field_params.MaxBlobsPerBlock {
+	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
+	if len(kzgs) > maxBlobsPerBlock {
 		return fmt.Errorf("too many kzg commitments in block: %d", len(kzgs))
 	}
 	return nil
--- a/beacon-chain/core/blocks/payload_test.go
+++ b/beacon-chain/core/blocks/payload_test.go
@@ -9,6 +9,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
 	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
@@ -253,7 +254,8 @@ func Test_IsExecutionBlockCapella(t *testing.T) {
 	require.NoError(t, err)
 	got, err := blocks.IsExecutionBlock(wrappedBlock.Body())
 	require.NoError(t, err)
-	require.Equal(t, false, got)
+	// #14614
+	require.Equal(t, true, got)
 }

 func Test_IsExecutionEnabled(t *testing.T) {
@@ -587,8 +589,7 @@ func Test_ProcessPayload(t *testing.T) {
 				ExecutionPayload: tt.payload,
 			})
 			require.NoError(t, err)
-			st, err := blocks.ProcessPayload(st, body)
-			if err != nil {
+			if err := blocks.ProcessPayload(st, body); err != nil {
 				require.Equal(t, tt.err.Error(), err.Error())
 			} else {
 				require.Equal(t, tt.err, err)
@@ -619,8 +620,7 @@ func Test_ProcessPayloadCapella(t *testing.T) {
 		ExecutionPayload: payload,
 	})
 	require.NoError(t, err)
-	_, err = blocks.ProcessPayload(st, body)
-	require.NoError(t, err)
+	require.NoError(t, blocks.ProcessPayload(st, body))
 }

 func Test_ProcessPayload_Blinded(t *testing.T) {
@@ -677,8 +677,7 @@ func Test_ProcessPayload_Blinded(t *testing.T) {
 				ExecutionPayloadHeader: p,
 			})
 			require.NoError(t, err)
-			st, err := blocks.ProcessPayload(st, body)
-			if err != nil {
+			if err := blocks.ProcessPayload(st, body); err != nil {
 				require.Equal(t, tt.err.Error(), err.Error())
 			} else {
 				require.Equal(t, tt.err, err)
@@ -925,10 +924,10 @@ func TestVerifyBlobCommitmentCount(t *testing.T) {
 	b := &ethpb.BeaconBlockDeneb{Body: &ethpb.BeaconBlockBodyDeneb{}}
 	rb, err := consensusblocks.NewBeaconBlock(b)
 	require.NoError(t, err)
-	require.NoError(t, blocks.VerifyBlobCommitmentCount(rb.Body()))
+	require.NoError(t, blocks.VerifyBlobCommitmentCount(rb.Slot(), rb.Body()))

-	b = &ethpb.BeaconBlockDeneb{Body: &ethpb.BeaconBlockBodyDeneb{BlobKzgCommitments: make([][]byte, fieldparams.MaxBlobsPerBlock+1)}}
+	b = &ethpb.BeaconBlockDeneb{Body: &ethpb.BeaconBlockBodyDeneb{BlobKzgCommitments: make([][]byte, params.BeaconConfig().MaxBlobsPerBlock(rb.Slot())+1)}}
 	rb, err = consensusblocks.NewBeaconBlock(b)
 	require.NoError(t, err)
-	require.ErrorContains(t, fmt.Sprintf("too many kzg commitments in block: %d", fieldparams.MaxBlobsPerBlock+1), blocks.VerifyBlobCommitmentCount(rb.Body()))
+	require.ErrorContains(t, fmt.Sprintf("too many kzg commitments in block: %d", params.BeaconConfig().MaxBlobsPerBlock(rb.Slot())+1), blocks.VerifyBlobCommitmentCount(rb.Slot(), rb.Body()))
 }
--- a/beacon-chain/core/blocks/signature.go
+++ b/beacon-chain/core/blocks/signature.go
@@ -96,6 +96,24 @@ func VerifyBlockHeaderSignature(beaconState state.BeaconState, header *ethpb.Sig
 	return signing.VerifyBlockHeaderSigningRoot(header.Header, proposerPubKey, header.Signature, domain)
 }

+func VerifyBlockHeaderSignatureUsingCurrentFork(beaconState state.BeaconState, header *ethpb.SignedBeaconBlockHeader) error {
+	currentEpoch := slots.ToEpoch(header.Header.Slot)
+	fork, err := forks.Fork(currentEpoch)
+	if err != nil {
+		return err
+	}
+	domain, err := signing.Domain(fork, currentEpoch, params.BeaconConfig().DomainBeaconProposer, beaconState.GenesisValidatorsRoot())
+	if err != nil {
+		return err
+	}
+	proposer, err := beaconState.ValidatorAtIndex(header.Header.ProposerIndex)
+	if err != nil {
+		return err
+	}
+	proposerPubKey := proposer.PublicKey
+	return signing.VerifyBlockHeaderSigningRoot(header.Header, proposerPubKey, header.Signature, domain)
+}
+
 // VerifyBlockSignatureUsingCurrentFork verifies the proposer signature of a beacon block. This differs
 // from the above method by not using fork data from the state and instead retrieving it
 // via the respective epoch.
--- a/beacon-chain/core/blocks/withdrawals.go
+++ b/beacon-chain/core/blocks/withdrawals.go
@@ -100,8 +100,11 @@ func ValidateBLSToExecutionChange(st state.ReadOnlyBeaconState, signed *ethpb.Si
 	if err != nil {
 		return nil, err
 	}
+	if val == nil {
+		return nil, errors.Wrap(errInvalidWithdrawalCredentials, "validator is nil") // This should not be possible.
+	}
 	cred := val.WithdrawalCredentials
-	if cred[0] != params.BeaconConfig().BLSWithdrawalPrefixByte {
+	if len(cred) < 2 || cred[0] != params.BeaconConfig().BLSWithdrawalPrefixByte {
 		return nil, errInvalidBLSPrefix
 	}

@@ -120,35 +123,36 @@ func ValidateBLSToExecutionChange(st state.ReadOnlyBeaconState, signed *ethpb.Si
 //
 // Spec pseudocode definition:
 //
-//	def process_withdrawals(state: BeaconState, payload: ExecutionPayload) -> None:
-//	    expected_withdrawals, partial_withdrawals_count = get_expected_withdrawals(state)  # [Modified in Electra:EIP7251]
+// def process_withdrawals(state: BeaconState, payload: ExecutionPayload) -> None:
 //
-//	    assert len(payload.withdrawals) == len(expected_withdrawals)
+//	expected_withdrawals, processed_partial_withdrawals_count = get_expected_withdrawals(state) # [Modified in Electra:EIP7251]
 //
-//	    for expected_withdrawal, withdrawal in zip(expected_withdrawals, payload.withdrawals):
-//	        assert withdrawal == expected_withdrawal
-//	        decrease_balance(state, withdrawal.validator_index, withdrawal.amount)
+//	assert len(payload.withdrawals) == len(expected_withdrawals)
 //
-//	    # Update pending partial withdrawals [New in Electra:EIP7251]
-//	    state.pending_partial_withdrawals = state.pending_partial_withdrawals[partial_withdrawals_count:]
+//	for expected_withdrawal, withdrawal in zip(expected_withdrawals, payload.withdrawals):
+//	     assert withdrawal == expected_withdrawal
+//	     decrease_balance(state, withdrawal.validator_index, withdrawal.amount)
 //
-//	    # Update the next withdrawal index if this block contained withdrawals
-//	    if len(expected_withdrawals) != 0:
-//	        latest_withdrawal = expected_withdrawals[-1]
-//	        state.next_withdrawal_index = WithdrawalIndex(latest_withdrawal.index + 1)
+//	# Update pending partial withdrawals [New in Electra:EIP7251]
+//	state.pending_partial_withdrawals = state.pending_partial_withdrawals[processed_partial_withdrawals_count:]
 //
-//	    # Update the next validator index to start the next withdrawal sweep
-//	    if len(expected_withdrawals) == MAX_WITHDRAWALS_PER_PAYLOAD:
-//	        # Next sweep starts after the latest withdrawal's validator index
-//	        next_validator_index = ValidatorIndex((expected_withdrawals[-1].validator_index + 1) % len(state.validators))
-//	        state.next_withdrawal_validator_index = next_validator_index
-//	    else:
-//	        # Advance sweep by the max length of the sweep if there was not a full set of withdrawals
-//	        next_index = state.next_withdrawal_validator_index + MAX_VALIDATORS_PER_WITHDRAWALS_SWEEP
-//	        next_validator_index = ValidatorIndex(next_index % len(state.validators))
-//	        state.next_withdrawal_validator_index = next_validator_index
+//	# Update the next withdrawal index if this block contained withdrawals
+//	if len(expected_withdrawals) != 0:
+//	    latest_withdrawal = expected_withdrawals[-1]
+//	    state.next_withdrawal_index = WithdrawalIndex(latest_withdrawal.index + 1)
+//
+//	# Update the next validator index to start the next withdrawal sweep
+//	if len(expected_withdrawals) == MAX_WITHDRAWALS_PER_PAYLOAD:
+//	    # Next sweep starts after the latest withdrawal's validator index
+//	    next_validator_index = ValidatorIndex((expected_withdrawals[-1].validator_index + 1) % len(state.validators))
+//	    state.next_withdrawal_validator_index = next_validator_index
+//	else:
+//	    # Advance sweep by the max length of the sweep if there was not a full set of withdrawals
+//	    next_index = state.next_withdrawal_validator_index + MAX_VALIDATORS_PER_WITHDRAWALS_SWEEP
+//	    next_validator_index = ValidatorIndex(next_index % len(state.validators))
+//	    state.next_withdrawal_validator_index = next_validator_index
 func ProcessWithdrawals(st state.BeaconState, executionData interfaces.ExecutionData) (state.BeaconState, error) {
-	expectedWithdrawals, partialWithdrawalsCount, err := st.ExpectedWithdrawals()
+	expectedWithdrawals, processedPartialWithdrawalsCount, err := st.ExpectedWithdrawals()
 	if err != nil {
 		return nil, errors.Wrap(err, "could not get expected withdrawals")
 	}
@@ -192,7 +196,7 @@ func ProcessWithdrawals(st state.BeaconState, executionData interfaces.Execution
 	}

 	if st.Version() >= version.Electra {
-		if err := st.DequeuePartialWithdrawals(partialWithdrawalsCount); err != nil {
+		if err := st.DequeuePendingPartialWithdrawals(processedPartialWithdrawalsCount); err != nil {
 			return nil, fmt.Errorf("unable to dequeue partial withdrawals from state: %w", err)
 		}
 	}
--- a/beacon-chain/core/blocks/withdrawals_test.go
+++ b/beacon-chain/core/blocks/withdrawals_test.go
@@ -113,7 +113,42 @@ func TestProcessBLSToExecutionChange(t *testing.T) {
 		require.NoError(t, err)
 		require.DeepEqual(t, digest[:], val.WithdrawalCredentials)
 	})
+	t.Run("nil validator does not panic", func(t *testing.T) {
+		priv, err := bls.RandKey()
+		require.NoError(t, err)
+		pubkey := priv.PublicKey().Marshal()

+		message := &ethpb.BLSToExecutionChange{
+			ToExecutionAddress: []byte{0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13},
+			ValidatorIndex:     0,
+			FromBlsPubkey:      pubkey,
+		}
+
+		registry := []*ethpb.Validator{
+			nil,
+		}
+		st, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
+			Validators: registry,
+			Fork: &ethpb.Fork{
+				CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
+				PreviousVersion: params.BeaconConfig().GenesisForkVersion,
+			},
+			Slot: params.BeaconConfig().SlotsPerEpoch * 5,
+		})
+		require.NoError(t, err)
+
+		signature, err := signing.ComputeDomainAndSign(st, time.CurrentEpoch(st), message, params.BeaconConfig().DomainBLSToExecutionChange, priv)
+		require.NoError(t, err)
+
+		signed := &ethpb.SignedBLSToExecutionChange{
+			Message:   message,
+			Signature: signature,
+		}
+		_, err = blocks.ValidateBLSToExecutionChange(st, signed)
+		// The state should return an empty validator, even when the validator object in the registry is
+		// nil. This error should return when the withdrawal credentials are invalid or too short.
+		require.ErrorIs(t, err, blocks.ErrInvalidBLSPrefix)
+	})
 	t.Run("non-existent validator", func(t *testing.T) {
 		priv, err := bls.RandKey()
 		require.NoError(t, err)
@@ -1117,7 +1152,7 @@ func TestProcessWithdrawals(t *testing.T) {
 						}
 						st, err = state_native.InitializeFromProtoUnsafeElectra(spb)
 						require.NoError(t, err)
-						p, err = consensusblocks.WrappedExecutionPayloadElectra(&enginev1.ExecutionPayloadElectra{Withdrawals: test.Args.Withdrawals})
+						p, err = consensusblocks.WrappedExecutionPayloadDeneb(&enginev1.ExecutionPayloadDeneb{Withdrawals: test.Args.Withdrawals})
 						require.NoError(t, err)
 					default:
 						t.Fatalf("Add a beacon state setup for version %s", version.String(fork))
--- a/beacon-chain/core/electra/BUILD.bazel
+++ b/beacon-chain/core/electra/BUILD.bazel
@@ -32,13 +32,16 @@ go_library(
        "//consensus-types/interfaces:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//contracts/deposit:go_default_library",
+        "//crypto/bls/common:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//math:go_default_library",
        "//monitoring/tracing/trace:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
+        "//runtime/version:go_default_library",
        "//time/slots:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/math:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
        "@com_github_sirupsen_logrus//:go_default_library",
    ],
@@ -52,24 +55,27 @@ go_test(
        "deposit_fuzz_test.go",
        "deposits_test.go",
        "effective_balance_updates_test.go",
+        "export_test.go",
        "registry_updates_test.go",
        "transition_test.go",
        "upgrade_test.go",
        "validator_test.go",
        "withdrawals_test.go",
    ],
+    embed = [":go_default_library"],
    deps = [
-        ":go_default_library",
        "//beacon-chain/core/helpers:go_default_library",
        "//beacon-chain/core/signing:go_default_library",
        "//beacon-chain/core/time:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//beacon-chain/state/state-native:go_default_library",
+        "//beacon-chain/state/testing:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//crypto/bls:go_default_library",
+        "//crypto/bls/common:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
--- a/beacon-chain/core/electra/churn_test.go
+++ b/beacon-chain/core/electra/churn_test.go
@@ -20,7 +20,7 @@ func createValidatorsWithTotalActiveBalance(totalBal primitives.Gwei) []*eth.Val
 	vals := make([]*eth.Validator, num)
 	for i := range vals {
 		wd := make([]byte, 32)
-		wd[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+		wd[0] = params.BeaconConfig().CompoundingWithdrawalPrefixByte
 		wd[31] = byte(i)

 		vals[i] = &eth.Validator{
--- a/beacon-chain/core/electra/consolidations.go
+++ b/beacon-chain/core/electra/consolidations.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"

+	"github.com/ethereum/go-ethereum/common/math"
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
@@ -15,6 +16,7 @@ import (
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	log "github.com/sirupsen/logrus"
 )

 // ProcessPendingConsolidations implements the spec definition below. This method makes mutating
@@ -22,25 +24,27 @@ import (
 //
 // Spec definition:
 //
-//	def process_pending_consolidations(state: BeaconState) -> None:
-//	    next_pending_consolidation = 0
-//	    for pending_consolidation in state.pending_consolidations:
-//	        source_validator = state.validators[pending_consolidation.source_index]
-//	        if source_validator.slashed:
-//	            next_pending_consolidation += 1
-//	            continue
-//	        if source_validator.withdrawable_epoch > get_current_epoch(state):
-//	            break
+// def process_pending_consolidations(state: BeaconState) -> None:
 //
-//	        # Churn any target excess active balance of target and raise its max
-//	        switch_to_compounding_validator(state, pending_consolidation.target_index)
-//	        # Move active balance to target. Excess balance is withdrawable.
-//	        active_balance = get_active_balance(state, pending_consolidation.source_index)
-//	        decrease_balance(state, pending_consolidation.source_index, active_balance)
-//	        increase_balance(state, pending_consolidation.target_index, active_balance)
+//	next_epoch = Epoch(get_current_epoch(state) + 1)
+//	next_pending_consolidation = 0
+//	for pending_consolidation in state.pending_consolidations:
+//	    source_validator = state.validators[pending_consolidation.source_index]
+//	    if source_validator.slashed:
 //	        next_pending_consolidation += 1
+//	        continue
+//	    if source_validator.withdrawable_epoch > next_epoch:
+//	        break
 //
-//	    state.pending_consolidations = state.pending_consolidations[next_pending_consolidation:]
+//	    # Calculate the consolidated balance
+//	    source_effective_balance = min(state.balances[pending_consolidation.source_index], source_validator.effective_balance)
+//
+//	    # Move active balance to target. Excess balance is withdrawable.
+//	    decrease_balance(state, pending_consolidation.source_index, source_effective_balance)
+//	    increase_balance(state, pending_consolidation.target_index, source_effective_balance)
+//	    next_pending_consolidation += 1
+//
+//	state.pending_consolidations = state.pending_consolidations[next_pending_consolidation:]
 func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) error {
 	_, span := trace.StartSpan(ctx, "electra.ProcessPendingConsolidations")
 	defer span.End()
@@ -51,37 +55,34 @@ func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) err

 	nextEpoch := slots.ToEpoch(st.Slot()) + 1

-	var nextPendingConsolidation uint64
 	pendingConsolidations, err := st.PendingConsolidations()
 	if err != nil {
 		return err
 	}
-
+	var nextPendingConsolidation uint64
 	for _, pc := range pendingConsolidations {
-		sourceValidator, err := st.ValidatorAtIndex(pc.SourceIndex)
+		sourceValidator, err := st.ValidatorAtIndexReadOnly(pc.SourceIndex)
 		if err != nil {
 			return err
 		}
-		if sourceValidator.Slashed {
+		if sourceValidator.Slashed() {
 			nextPendingConsolidation++
 			continue
 		}
-		if sourceValidator.WithdrawableEpoch > nextEpoch {
+		if sourceValidator.WithdrawableEpoch() > nextEpoch {
 			break
 		}

-		if err := SwitchToCompoundingValidator(st, pc.TargetIndex); err != nil {
-			return err
-		}
-
-		activeBalance, err := st.ActiveBalanceAtIndex(pc.SourceIndex)
+		validatorBalance, err := st.BalanceAtIndex(pc.SourceIndex)
 		if err != nil {
 			return err
 		}
-		if err := helpers.DecreaseBalance(st, pc.SourceIndex, activeBalance); err != nil {
+		b := min(validatorBalance, sourceValidator.EffectiveBalance())
+
+		if err := helpers.DecreaseBalance(st, pc.SourceIndex, b); err != nil {
 			return err
 		}
-		if err := helpers.IncreaseBalance(st, pc.TargetIndex, activeBalance); err != nil {
+		if err := helpers.IncreaseBalance(st, pc.TargetIndex, b); err != nil {
 			return err
 		}
 		nextPendingConsolidation++
@@ -101,6 +102,16 @@ func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) err
 //	    state: BeaconState,
 //	    consolidation_request: ConsolidationRequest
 //	) -> None:
+//	    if is_valid_switch_to_compounding_request(state, consolidation_request):
+//	        validator_pubkeys = [v.pubkey for v in state.validators]
+//	        request_source_pubkey = consolidation_request.source_pubkey
+//	        source_index = ValidatorIndex(validator_pubkeys.index(request_source_pubkey))
+//	        switch_to_compounding_validator(state, source_index)
+//	        return
+//
+//	    # Verify that source != target, so a consolidation cannot be used as an exit.
+//	    if consolidation_request.source_pubkey == consolidation_request.target_pubkey:
+//	        return
 //	    # If the pending consolidations queue is full, consolidation requests are ignored
 //	    if len(state.pending_consolidations) == PENDING_CONSOLIDATIONS_LIMIT:
 //	        return
@@ -121,10 +132,6 @@ func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) err
 //	    source_validator = state.validators[source_index]
 //	    target_validator = state.validators[target_index]
 //
-//	    # Verify that source != target, so a consolidation cannot be used as an exit.
-//	    if source_index == target_index:
-//	        return
-//
 //	    # Verify source withdrawal credentials
 //	    has_correct_credential = has_execution_withdrawal_credential(source_validator)
 //	    is_correct_source_address = (
@@ -133,8 +140,8 @@ func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) err
 //	    if not (has_correct_credential and is_correct_source_address):
 //	        return
 //
-//	    # Verify that target has execution withdrawal credentials
-//	    if not has_execution_withdrawal_credential(target_validator):
+//	    # Verify that target has compounding withdrawal credentials
+//	    if not has_compounding_withdrawal_credential(target_validator):
 //	        return
 //
 //	    # Verify the source and the target are active
@@ -149,6 +156,13 @@ func ProcessPendingConsolidations(ctx context.Context, st state.BeaconState) err
 //	    if target_validator.exit_epoch != FAR_FUTURE_EPOCH:
 //	        return
 //
+//	    # Verify the source has been active long enough
+//	    if current_epoch < source_validator.activation_epoch + SHARD_COMMITTEE_PERIOD:
+//	        return
+//
+//	    # Verify the source has no pending withdrawals in the queue
+//	    if get_pending_balance_to_withdraw(state, source_index) > 0:
+//	        return
 //	    # Initiate source validator exit and append pending consolidation
 //	    source_validator.exit_epoch = compute_consolidation_epoch_and_update_churn(
 //	        state, source_validator.effective_balance
@@ -164,15 +178,6 @@ func ProcessConsolidationRequests(ctx context.Context, st state.BeaconState, req
 	if len(reqs) == 0 || st == nil {
 		return nil
 	}
-
-	activeBal, err := helpers.TotalActiveBalance(st)
-	if err != nil {
-		return err
-	}
-	churnLimit := helpers.ConsolidationChurnLimit(primitives.Gwei(activeBal))
-	if churnLimit <= primitives.Gwei(params.BeaconConfig().MinActivationBalance) {
-		return nil
-	}
 	curEpoch := slots.ToEpoch(st.Slot())
 	ffe := params.BeaconConfig().FarFutureEpoch
 	minValWithdrawDelay := params.BeaconConfig().MinValidatorWithdrawabilityDelay
@@ -182,22 +187,44 @@ func ProcessConsolidationRequests(ctx context.Context, st state.BeaconState, req
 		if ctx.Err() != nil {
 			return fmt.Errorf("cannot process consolidation requests: %w", ctx.Err())
 		}
+		if IsValidSwitchToCompoundingRequest(st, cr) {
+			srcIdx, ok := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(cr.SourcePubkey))
+			if !ok {
+				log.Error("failed to find source validator index")
+				continue
+			}
+			if err := SwitchToCompoundingValidator(st, srcIdx); err != nil {
+				log.WithError(err).Error("failed to switch to compounding validator")
+			}
+			continue
+		}
+		sourcePubkey := bytesutil.ToBytes48(cr.SourcePubkey)
+		targetPubkey := bytesutil.ToBytes48(cr.TargetPubkey)
+		if sourcePubkey == targetPubkey {
+			continue
+		}
+
 		if npc, err := st.NumPendingConsolidations(); err != nil {
 			return fmt.Errorf("failed to fetch number of pending consolidations: %w", err) // This should never happen.
 		} else if npc >= pcLimit {
 			return nil
 		}

-		srcIdx, ok := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(cr.SourcePubkey))
-		if !ok {
-			continue
+		activeBal, err := helpers.TotalActiveBalance(st)
+		if err != nil {
+			return err
 		}
-		tgtIdx, ok := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(cr.TargetPubkey))
-		if !ok {
-			continue
+		churnLimit := helpers.ConsolidationChurnLimit(primitives.Gwei(activeBal))
+		if churnLimit <= primitives.Gwei(params.BeaconConfig().MinActivationBalance) {
+			return nil
 		}

-		if srcIdx == tgtIdx {
+		srcIdx, ok := st.ValidatorIndexByPubkey(sourcePubkey)
+		if !ok {
+			continue
+		}
+		tgtIdx, ok := st.ValidatorIndexByPubkey(targetPubkey)
+		if !ok {
 			continue
 		}

@@ -221,7 +248,7 @@ func ProcessConsolidationRequests(ctx context.Context, st state.BeaconState, req
 		}

 		// Target validator must have their withdrawal credentials set appropriately.
-		if !helpers.HasExecutionWithdrawalCredentials(tgtV) {
+		if !helpers.HasCompoundingWithdrawalCredential(tgtV) {
 			continue
 		}

@@ -234,10 +261,28 @@ func ProcessConsolidationRequests(ctx context.Context, st state.BeaconState, req
 			continue
 		}

+		e, overflow := math.SafeAdd(uint64(srcV.ActivationEpoch), uint64(params.BeaconConfig().ShardCommitteePeriod))
+		if overflow {
+			log.Error("Overflow when adding activation epoch and shard committee period")
+			continue
+		}
+		if uint64(curEpoch) < e {
+			continue
+		}
+		bal, err := st.PendingBalanceToWithdraw(srcIdx)
+		if err != nil {
+			log.WithError(err).Error("failed to fetch pending balance to withdraw")
+			continue
+		}
+		if bal > 0 {
+			continue
+		}
+
 		// Initiate the exit of the source validator.
 		exitEpoch, err := ComputeConsolidationEpochAndUpdateChurn(ctx, st, primitives.Gwei(srcV.EffectiveBalance))
 		if err != nil {
-			return fmt.Errorf("failed to compute consolidaiton epoch: %w", err)
+			log.WithError(err).Error("failed to compute consolidation epoch")
+			continue
 		}
 		srcV.ExitEpoch = exitEpoch
 		srcV.WithdrawableEpoch = exitEpoch + minValWithdrawDelay
@@ -252,3 +297,84 @@ func ProcessConsolidationRequests(ctx context.Context, st state.BeaconState, req

 	return nil
 }
+
+// IsValidSwitchToCompoundingRequest returns true if the given consolidation request is valid for switching to compounding.
+//
+// Spec code:
+//
+// def is_valid_switch_to_compounding_request(
+//
+//	state: BeaconState,
+//	consolidation_request: ConsolidationRequest
+//
+// ) -> bool:
+//
+//	# Switch to compounding requires source and target be equal
+//	if consolidation_request.source_pubkey != consolidation_request.target_pubkey:
+//	    return False
+//
+//	# Verify pubkey exists
+//	source_pubkey = consolidation_request.source_pubkey
+//	validator_pubkeys = [v.pubkey for v in state.validators]
+//	if source_pubkey not in validator_pubkeys:
+//	    return False
+//
+//	source_validator = state.validators[ValidatorIndex(validator_pubkeys.index(source_pubkey))]
+//
+//	# Verify request has been authorized
+//	if source_validator.withdrawal_credentials[12:] != consolidation_request.source_address:
+//	    return False
+//
+//	# Verify source withdrawal credentials
+//	if not has_eth1_withdrawal_credential(source_validator):
+//	    return False
+//
+//	# Verify the source is active
+//	current_epoch = get_current_epoch(state)
+//	if not is_active_validator(source_validator, current_epoch):
+//	    return False
+//
+//	# Verify exit for source has not been initiated
+//	if source_validator.exit_epoch != FAR_FUTURE_EPOCH:
+//	    return False
+//
+//	return True
+func IsValidSwitchToCompoundingRequest(st state.BeaconState, req *enginev1.ConsolidationRequest) bool {
+	if req.SourcePubkey == nil || req.TargetPubkey == nil {
+		return false
+	}
+
+	if !bytes.Equal(req.SourcePubkey, req.TargetPubkey) {
+		return false
+	}
+
+	srcIdx, ok := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(req.SourcePubkey))
+	if !ok {
+		return false
+	}
+	// As per the consensus specification, this error is not considered an assertion.
+	// Therefore, if the source_pubkey is not found in validator_pubkeys, we simply return false.
+	srcV, err := st.ValidatorAtIndexReadOnly(srcIdx)
+	if err != nil {
+		return false
+	}
+	sourceAddress := req.SourceAddress
+	withdrawalCreds := srcV.GetWithdrawalCredentials()
+	if len(withdrawalCreds) != 32 || len(sourceAddress) != 20 || !bytes.HasSuffix(withdrawalCreds, sourceAddress) {
+		return false
+	}
+
+	if !helpers.HasETH1WithdrawalCredential(srcV) {
+		return false
+	}
+
+	curEpoch := slots.ToEpoch(st.Slot())
+	if !helpers.IsActiveValidatorUsingTrie(srcV, curEpoch) {
+		return false
+	}
+
+	if srcV.ExitEpoch() != params.BeaconConfig().FarFutureEpoch {
+		return false
+	}
+	return true
+}
--- a/beacon-chain/core/electra/consolidations_test.go
+++ b/beacon-chain/core/electra/consolidations_test.go
@@ -13,6 +13,7 @@ import (
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/prysmaticlabs/prysm/v5/testing/util"
 )

 func TestProcessPendingConsolidations(t *testing.T) {
@@ -45,6 +46,7 @@ func TestProcessPendingConsolidations(t *testing.T) {
 					Validators: []*eth.Validator{
 						{
 							WithdrawalCredentials: []byte{0x01, 0xFF},
+							EffectiveBalance:      params.BeaconConfig().MinActivationBalance,
 						},
 						{
 							WithdrawalCredentials: []byte{0x01, 0xAB},
@@ -80,10 +82,10 @@ func TestProcessPendingConsolidations(t *testing.T) {
 				require.NoError(t, err)
 				require.Equal(t, uint64(0), num)

-				// v1 is switched to compounding validator.
+				// v1 withdrawal credentials should not be updated.
 				v1, err := st.ValidatorAtIndex(1)
 				require.NoError(t, err)
-				require.Equal(t, params.BeaconConfig().CompoundingWithdrawalPrefixByte, v1.WithdrawalCredentials[0])
+				require.Equal(t, params.BeaconConfig().ETH1AddressWithdrawalPrefixByte, v1.WithdrawalCredentials[0])
 			},
 			wantErr: false,
 		},
@@ -201,38 +203,6 @@ func TestProcessPendingConsolidations(t *testing.T) {
 	}
 }

-func stateWithActiveBalanceETH(t *testing.T, balETH uint64) state.BeaconState {
-	gwei := balETH * 1_000_000_000
-	balPerVal := params.BeaconConfig().MinActivationBalance
-	numVals := gwei / balPerVal
-
-	vals := make([]*eth.Validator, numVals)
-	bals := make([]uint64, numVals)
-	for i := uint64(0); i < numVals; i++ {
-		wc := make([]byte, 32)
-		wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
-		wc[31] = byte(i)
-		vals[i] = &eth.Validator{
-			ActivationEpoch:       0,
-			ExitEpoch:             params.BeaconConfig().FarFutureEpoch,
-			EffectiveBalance:      balPerVal,
-			WithdrawalCredentials: wc,
-		}
-		bals[i] = balPerVal
-	}
-	st, err := state_native.InitializeFromProtoUnsafeElectra(&eth.BeaconStateElectra{
-		Slot:       10 * params.BeaconConfig().SlotsPerEpoch,
-		Validators: vals,
-		Balances:   bals,
-		Fork: &eth.Fork{
-			CurrentVersion: params.BeaconConfig().ElectraForkVersion,
-		},
-	})
-	require.NoError(t, err)
-
-	return st
-}
-
 func TestProcessConsolidationRequests(t *testing.T) {
 	tests := []struct {
 		name     string
@@ -244,15 +214,22 @@ func TestProcessConsolidationRequests(t *testing.T) {
 			name: "one valid request",
 			state: func() state.BeaconState {
 				st := &eth.BeaconStateElectra{
+					Slot:       params.BeaconConfig().SlotsPerEpoch.Mul(uint64(params.BeaconConfig().ShardCommitteePeriod)),
 					Validators: createValidatorsWithTotalActiveBalance(32000000000000000), // 32M ETH
 				}
 				// Validator scenario setup. See comments in reqs section.
 				st.Validators[3].WithdrawalCredentials = bytesutil.Bytes32(0)
-				st.Validators[8].WithdrawalCredentials = bytesutil.Bytes32(0)
+				st.Validators[8].WithdrawalCredentials = bytesutil.Bytes32(1)
 				st.Validators[9].ActivationEpoch = params.BeaconConfig().FarFutureEpoch
 				st.Validators[12].ActivationEpoch = params.BeaconConfig().FarFutureEpoch
 				st.Validators[13].ExitEpoch = 10
 				st.Validators[16].ExitEpoch = 10
+				st.PendingPartialWithdrawals = []*eth.PendingPartialWithdrawal{
+					{
+						Index:  17,
+						Amount: 100,
+					},
+				}
 				s, err := state_native.InitializeFromProtoElectra(st)
 				require.NoError(t, err)
 				return s
@@ -270,7 +247,7 @@ func TestProcessConsolidationRequests(t *testing.T) {
 					SourcePubkey:  []byte("val_5"),
 					TargetPubkey:  []byte("val_6"),
 				},
-				// Target does not have their withdrawal credentials set appropriately.
+				// Target does not have their withdrawal credentials set appropriately. (Using eth1 address prefix)
 				{
 					SourceAddress: append(bytesutil.PadTo(nil, 19), byte(7)),
 					SourcePubkey:  []byte("val_7"),
@@ -318,6 +295,12 @@ func TestProcessConsolidationRequests(t *testing.T) {
 					SourcePubkey:  []byte("val_0"),
 					TargetPubkey:  []byte("val_0"),
 				},
+				// Has pending partial withdrawal
+				{
+					SourceAddress: append(bytesutil.PadTo(nil, 19), byte(0)),
+					SourcePubkey:  []byte("val_17"),
+					TargetPubkey:  []byte("val_1"),
+				},
 				// Valid consolidation request. This should be last to ensure invalid requests do
 				// not end the processing early.
 				{
@@ -378,6 +361,7 @@ func TestProcessConsolidationRequests(t *testing.T) {
 			name: "pending consolidations limit reached during processing",
 			state: func() state.BeaconState {
 				st := &eth.BeaconStateElectra{
+					Slot:                  params.BeaconConfig().SlotsPerEpoch.Mul(uint64(params.BeaconConfig().ShardCommitteePeriod)),
 					Validators:            createValidatorsWithTotalActiveBalance(32000000000000000), // 32M ETH
 					PendingConsolidations: make([]*eth.PendingConsolidation, params.BeaconConfig().PendingConsolidationsLimit-1),
 				}
@@ -428,3 +412,87 @@ func TestProcessConsolidationRequests(t *testing.T) {
 		})
 	}
 }
+
+func TestIsValidSwitchToCompoundingRequest(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateElectra(t, 1)
+	t.Run("nil source pubkey", func(t *testing.T) {
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourcePubkey: nil,
+			TargetPubkey: []byte{'a'},
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("nil target pubkey", func(t *testing.T) {
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			TargetPubkey: nil,
+			SourcePubkey: []byte{'a'},
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("different source and target pubkey", func(t *testing.T) {
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			TargetPubkey: []byte{'a'},
+			SourcePubkey: []byte{'b'},
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("source validator not found in state", func(t *testing.T) {
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourceAddress: make([]byte, 20),
+			TargetPubkey:  []byte{'a'},
+			SourcePubkey:  []byte{'a'},
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("incorrect source address", func(t *testing.T) {
+		v, err := st.ValidatorAtIndex(0)
+		require.NoError(t, err)
+		pubkey := v.PublicKey
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourceAddress: make([]byte, 20),
+			TargetPubkey:  pubkey,
+			SourcePubkey:  pubkey,
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("incorrect eth1 withdrawal credential", func(t *testing.T) {
+		v, err := st.ValidatorAtIndex(0)
+		require.NoError(t, err)
+		pubkey := v.PublicKey
+		wc := v.WithdrawalCredentials
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourceAddress: wc[12:],
+			TargetPubkey:  pubkey,
+			SourcePubkey:  pubkey,
+		})
+		require.Equal(t, false, ok)
+	})
+	t.Run("is valid compounding request", func(t *testing.T) {
+		v, err := st.ValidatorAtIndex(0)
+		require.NoError(t, err)
+		pubkey := v.PublicKey
+		wc := v.WithdrawalCredentials
+		v.WithdrawalCredentials[0] = 1
+		require.NoError(t, st.UpdateValidatorAtIndex(0, v))
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourceAddress: wc[12:],
+			TargetPubkey:  pubkey,
+			SourcePubkey:  pubkey,
+		})
+		require.Equal(t, true, ok)
+	})
+	t.Run("already has an exit epoch", func(t *testing.T) {
+		v, err := st.ValidatorAtIndex(0)
+		require.NoError(t, err)
+		pubkey := v.PublicKey
+		wc := v.WithdrawalCredentials
+		v.ExitEpoch = 100
+		require.NoError(t, st.UpdateValidatorAtIndex(0, v))
+		ok := electra.IsValidSwitchToCompoundingRequest(st, &enginev1.ConsolidationRequest{
+			SourceAddress: wc[12:],
+			TargetPubkey:  pubkey,
+			SourcePubkey:  pubkey,
+		})
+		require.Equal(t, false, ok)
+	})
+}
--- a/beacon-chain/core/electra/deposits.go
+++ b/beacon-chain/core/electra/deposits.go
@@ -2,21 +2,21 @@ package electra

 import (
 	"context"
-	"fmt"

 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/signing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/contracts/deposit"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
 	log "github.com/sirupsen/logrus"
 )
@@ -38,7 +38,7 @@ func ProcessDeposits(
 	defer span.End()
 	// Attempt to verify all deposit signatures at once, if this fails then fall back to processing
 	// individual deposits with signature verification enabled.
-	batchVerified, err := blocks.BatchVerifyDepositsSignatures(ctx, deposits)
+	allSignaturesVerified, err := blocks.BatchVerifyDepositsSignatures(ctx, deposits)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not verify deposit signatures in batch")
 	}
@@ -47,7 +47,7 @@ func ProcessDeposits(
 		if d == nil || d.Data == nil {
 			return nil, errors.New("got a nil deposit in block")
 		}
-		beaconState, err = ProcessDeposit(beaconState, d, batchVerified)
+		beaconState, err = ProcessDeposit(beaconState, d, allSignaturesVerified)
 		if err != nil {
 			return nil, errors.Wrapf(err, "could not process deposit from %#x", bytesutil.Trunc(d.Data.PublicKey))
 		}
@@ -82,7 +82,7 @@ func ProcessDeposits(
 //	  amount=deposit.data.amount,
 //	  signature=deposit.data.signature,
 //	 )
-func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verifySignature bool) (state.BeaconState, error) {
+func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, allSignaturesVerified bool) (state.BeaconState, error) {
 	if err := blocks.VerifyDeposit(beaconState, deposit); err != nil {
 		if deposit == nil || deposit.Data == nil {
 			return nil, err
@@ -92,37 +92,49 @@ func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verif
 	if err := beaconState.SetEth1DepositIndex(beaconState.Eth1DepositIndex() + 1); err != nil {
 		return nil, err
 	}
-	return ApplyDeposit(beaconState, deposit.Data, verifySignature)
+	return ApplyDeposit(beaconState, deposit.Data, allSignaturesVerified)
 }

-// ApplyDeposit
-// def apply_deposit(state: BeaconState, pubkey: BLSPubkey, withdrawal_credentials: Bytes32, amount: uint64, signature: BLSSignature) -> None:
-// validator_pubkeys = [v.pubkey for v in state.validators]
-// if pubkey not in validator_pubkeys:
+// ApplyDeposit adds the incoming deposit as a pending deposit on the state
 //
-//	# Verify the deposit signature (proof of possession) which is not checked by the deposit contract
-//	if is_valid_deposit_signature(pubkey, withdrawal_credentials, amount, signature):
-//	  add_validator_to_registry(state, pubkey, withdrawal_credentials, amount)
+// Spec pseudocode definition:
+// def apply_deposit(state: BeaconState,
 //
-// else:
-//
-//	# Increase balance by deposit amount
-//	index = ValidatorIndex(validator_pubkeys.index(pubkey))
-//	state.pending_balance_deposits.append(PendingBalanceDeposit(index=index, amount=amount))  # [Modified in Electra:EIP-7251]
-//	# Check if valid deposit switch to compounding credentials
-//
-// if ( is_compounding_withdrawal_credential(withdrawal_credentials) and has_eth1_withdrawal_credential(state.validators[index])
-//
-//	 and is_valid_deposit_signature(pubkey, withdrawal_credentials, amount, signature)
-//	):
-//	 switch_to_compounding_validator(state, index)
-func ApplyDeposit(beaconState state.BeaconState, data *ethpb.Deposit_Data, verifySignature bool) (state.BeaconState, error) {
+//	              pubkey: BLSPubkey,
+//	              withdrawal_credentials: Bytes32,
+//	              amount: uint64,
+//	              signature: BLSSignature) -> None:
+//	validator_pubkeys = [v.pubkey for v in state.validators]
+//	if pubkey not in validator_pubkeys:
+//	    # Verify the deposit signature (proof of possession) which is not checked by the deposit contract
+//	    if is_valid_deposit_signature(pubkey, withdrawal_credentials, amount, signature):
+//	        add_validator_to_registry(state, pubkey, withdrawal_credentials, Gwei(0))  # [Modified in Electra:EIP7251]
+//	        # [New in Electra:EIP7251]
+//	        state.pending_deposits.append(PendingDeposit(
+//	            pubkey=pubkey,
+//	            withdrawal_credentials=withdrawal_credentials,
+//	            amount=amount,
+//	            signature=signature,
+//	            slot=GENESIS_SLOT,  # Use GENESIS_SLOT to distinguish from a pending deposit request
+//	        ))
+//	else:
+//	    # Increase balance by deposit amount
+//	    # [Modified in Electra:EIP7251]
+//	    state.pending_deposits.append(PendingDeposit(
+//	        pubkey=pubkey,
+//	        withdrawal_credentials=withdrawal_credentials,
+//	        amount=amount,
+//	        signature=signature,
+//	        slot=GENESIS_SLOT  # Use GENESIS_SLOT to distinguish from a pending deposit request
+//	    ))
+func ApplyDeposit(beaconState state.BeaconState, data *ethpb.Deposit_Data, allSignaturesVerified bool) (state.BeaconState, error) {
 	pubKey := data.PublicKey
 	amount := data.Amount
 	withdrawalCredentials := data.WithdrawalCredentials
-	index, ok := beaconState.ValidatorIndexByPubkey(bytesutil.ToBytes48(pubKey))
+	signature := data.Signature
+	_, ok := beaconState.ValidatorIndexByPubkey(bytesutil.ToBytes48(pubKey))
 	if !ok {
-		if verifySignature {
+		if !allSignaturesVerified {
 			valid, err := IsValidDepositSignature(data)
 			if err != nil {
 				return nil, errors.Wrap(err, "could not verify deposit signature")
@@ -131,32 +143,20 @@ func ApplyDeposit(beaconState state.BeaconState, data *ethpb.Deposit_Data, verif
 				return beaconState, nil
 			}
 		}
-		if err := AddValidatorToRegistry(beaconState, pubKey, withdrawalCredentials, amount); err != nil {
+
+		if err := AddValidatorToRegistry(beaconState, pubKey, withdrawalCredentials, 0); err != nil { // # [Modified in Electra:EIP7251]
 			return nil, errors.Wrap(err, "could not add validator to registry")
 		}
-	} else {
-		// no validation on top-ups (phase0 feature). no validation before state change
-		if err := beaconState.AppendPendingBalanceDeposit(index, amount); err != nil {
-			return nil, err
-		}
-		val, err := beaconState.ValidatorAtIndex(index)
-		if err != nil {
-			return nil, err
-		}
-		if helpers.IsCompoundingWithdrawalCredential(withdrawalCredentials) && helpers.HasETH1WithdrawalCredential(val) {
-			if verifySignature {
-				valid, err := IsValidDepositSignature(data)
-				if err != nil {
-					return nil, errors.Wrap(err, "could not verify deposit signature")
-				}
-				if !valid {
-					return beaconState, nil
-				}
-			}
-			if err := SwitchToCompoundingValidator(beaconState, index); err != nil {
-				return nil, errors.Wrap(err, "could not switch to compound validator")
-			}
-		}
+	}
+	// no validation on top-ups (phase0 feature). no validation before state change
+	if err := beaconState.AppendPendingDeposit(&ethpb.PendingDeposit{
+		PublicKey:             pubKey,
+		WithdrawalCredentials: withdrawalCredentials,
+		Amount:                amount,
+		Signature:             signature,
+		Slot:                  params.BeaconConfig().GenesisSlot,
+	}); err != nil {
+		return nil, err
 	}
 	return beaconState, nil
 }
@@ -185,152 +185,386 @@ func verifyDepositDataSigningRoot(obj *ethpb.Deposit_Data, domain []byte) error
 	return deposit.VerifyDepositSignature(obj, domain)
 }

-// ProcessPendingBalanceDeposits implements the spec definition below. This method mutates the state.
+// ProcessPendingDeposits implements the spec definition below. This method mutates the state.
+// Iterating over `pending_deposits` queue this function runs the following checks before applying pending deposit:
+// 1. All Eth1 bridge deposits are processed before the first deposit request gets processed.
+// 2. Deposit position in the queue is finalized.
+// 3. Deposit does not exceed the `MAX_PENDING_DEPOSITS_PER_EPOCH` limit.
+// 4. Deposit does not exceed the activation churn limit.
 //
 // Spec definition:
 //
-//	def process_pending_balance_deposits(state: BeaconState) -> None:
-//	    available_for_processing = state.deposit_balance_to_consume + get_activation_exit_churn_limit(state)
-//	    processed_amount = 0
-//	    next_deposit_index = 0
-//	    deposits_to_postpone = []
+// def process_pending_deposits(state: BeaconState) -> None:
 //
-//	    for deposit in state.pending_balance_deposits:
-//	        validator = state.validators[deposit.index]
+//	next_epoch = Epoch(get_current_epoch(state) + 1)
+//	available_for_processing = state.deposit_balance_to_consume + get_activation_exit_churn_limit(state)
+//	processed_amount = 0
+//	next_deposit_index = 0
+//	deposits_to_postpone = []
+//	is_churn_limit_reached = False
+//	finalized_slot = compute_start_slot_at_epoch(state.finalized_checkpoint.epoch)
+//
+//	for deposit in state.pending_deposits:
+//	    # Do not process deposit requests if Eth1 bridge deposits are not yet applied.
+//	    if (
+//	        # Is deposit request
+//	        deposit.slot > GENESIS_SLOT and
+//	        # There are pending Eth1 bridge deposits
+//	        state.eth1_deposit_index < state.deposit_requests_start_index
+//	    ):
+//	        break
+//
+//	    # Check if deposit has been finalized, otherwise, stop processing.
+//	    if deposit.slot > finalized_slot:
+//	        break
+//
+//	    # Check if number of processed deposits has not reached the limit, otherwise, stop processing.
+//	    if next_deposit_index >= MAX_PENDING_DEPOSITS_PER_EPOCH:
+//	        break
+//
+//	    # Read validator state
+//	    is_validator_exited = False
+//	    is_validator_withdrawn = False
+//	    validator_pubkeys = [v.pubkey for v in state.validators]
+//	    if deposit.pubkey in validator_pubkeys:
+//	        validator = state.validators[ValidatorIndex(validator_pubkeys.index(deposit.pubkey))]
+//	        is_validator_exited = validator.exit_epoch < FAR_FUTURE_EPOCH
+//	        is_validator_withdrawn = validator.withdrawable_epoch < next_epoch
+//
+//	    if is_validator_withdrawn:
+//	        # Deposited balance will never become active. Increase balance but do not consume churn
+//	        apply_pending_deposit(state, deposit)
+//	    elif is_validator_exited:
 //	        # Validator is exiting, postpone the deposit until after withdrawable epoch
-//	        if validator.exit_epoch < FAR_FUTURE_EPOCH:
-//	            if get_current_epoch(state) <= validator.withdrawable_epoch:
-//	                deposits_to_postpone.append(deposit)
-//	            # Deposited balance will never become active. Increase balance but do not consume churn
-//	            else:
-//	                increase_balance(state, deposit.index, deposit.amount)
-//	        # Validator is not exiting, attempt to process deposit
-//	        else:
-//	            # Deposit does not fit in the churn, no more deposit processing in this epoch.
-//	            if processed_amount + deposit.amount > available_for_processing:
-//	                break
-//	            # Deposit fits in the churn, process it. Increase balance and consume churn.
-//	            else:
-//	                increase_balance(state, deposit.index, deposit.amount)
-//	                processed_amount += deposit.amount
-//	        # Regardless of how the deposit was handled, we move on in the queue.
-//	        next_deposit_index += 1
-//
-//	    state.pending_balance_deposits = state.pending_balance_deposits[next_deposit_index:]
-//
-//	    if len(state.pending_balance_deposits) == 0:
-//	        state.deposit_balance_to_consume = Gwei(0)
+//	        deposits_to_postpone.append(deposit)
 //	    else:
-//	        state.deposit_balance_to_consume = available_for_processing - processed_amount
+//	        # Check if deposit fits in the churn, otherwise, do no more deposit processing in this epoch.
+//	        is_churn_limit_reached = processed_amount + deposit.amount > available_for_processing
+//	        if is_churn_limit_reached:
+//	            break
 //
-//	    state.pending_balance_deposits += deposits_to_postpone
-func ProcessPendingBalanceDeposits(ctx context.Context, st state.BeaconState, activeBalance primitives.Gwei) error {
-	_, span := trace.StartSpan(ctx, "electra.ProcessPendingBalanceDeposits")
+//	        # Consume churn and apply deposit.
+//	        processed_amount += deposit.amount
+//	        apply_pending_deposit(state, deposit)
+//
+//	    # Regardless of how the deposit was handled, we move on in the queue.
+//	    next_deposit_index += 1
+//
+//	state.pending_deposits = state.pending_deposits[next_deposit_index:] + deposits_to_postpone
+//
+//	# Accumulate churn only if the churn limit has been hit.
+//	if is_churn_limit_reached:
+//	    state.deposit_balance_to_consume = available_for_processing - processed_amount
+//	else:
+//	    state.deposit_balance_to_consume = Gwei(0)
+func ProcessPendingDeposits(ctx context.Context, st state.BeaconState, activeBalance primitives.Gwei) error {
+	_, span := trace.StartSpan(ctx, "electra.ProcessPendingDeposits")
 	defer span.End()

 	if st == nil || st.IsNil() {
 		return errors.New("nil state")
 	}

+	// constants & initializations
+	nextEpoch := slots.ToEpoch(st.Slot()) + 1
+	processedAmount := uint64(0)
+	nextDepositIndex := uint64(0)
+	isChurnLimitReached := false
+
+	var pendingDepositsToBatchVerify []*ethpb.PendingDeposit
+	var pendingDepositsToPostpone []*ethpb.PendingDeposit
+
 	depBalToConsume, err := st.DepositBalanceToConsume()
 	if err != nil {
-		return err
+		return errors.Wrap(err, "could not get deposit balance to consume")
 	}
 	availableForProcessing := depBalToConsume + helpers.ActivationExitChurnLimit(activeBalance)
-	processedAmount := uint64(0)
-	nextDepositIndex := 0
-	var depositsToPostpone []*eth.PendingBalanceDeposit

-	deposits, err := st.PendingBalanceDeposits()
+	finalizedSlot, err := slots.EpochStart(st.FinalizedCheckpoint().Epoch)
+	if err != nil {
+		return errors.Wrap(err, "could not get finalized slot")
+	}
+
+	startIndex, err := st.DepositRequestsStartIndex()
+	if err != nil {
+		return errors.Wrap(err, "could not get starting pendingDeposit index")
+	}
+
+	pendingDeposits, err := st.PendingDeposits()
 	if err != nil {
 		return err
 	}
-
-	// constants
-	ffe := params.BeaconConfig().FarFutureEpoch
-	nextEpoch := slots.ToEpoch(st.Slot()) + 1
-
-	for _, balanceDeposit := range deposits {
-		v, err := st.ValidatorAtIndexReadOnly(balanceDeposit.Index)
-		if err != nil {
-			return fmt.Errorf("failed to fetch validator at index: %w", err)
+	for _, pendingDeposit := range pendingDeposits {
+		// Do not process pendingDeposit requests if Eth1 bridge deposits are not yet applied.
+		if pendingDeposit.Slot > params.BeaconConfig().GenesisSlot && st.Eth1DepositIndex() < startIndex {
+			break
 		}

-		// If the validator is currently exiting, postpone the deposit until after the withdrawable
-		// epoch.
-		if v.ExitEpoch() < ffe {
-			if nextEpoch <= v.WithdrawableEpoch() {
-				depositsToPostpone = append(depositsToPostpone, balanceDeposit)
-			} else {
-				// The deposited balance will never become active. Therefore, we increase the balance but do
-				// not consume the churn.
-				if err := helpers.IncreaseBalance(st, balanceDeposit.Index, balanceDeposit.Amount); err != nil {
-					return err
-				}
+		// Check if pendingDeposit has been finalized, otherwise, stop processing.
+		if pendingDeposit.Slot > finalizedSlot {
+			break
+		}
+
+		// Check if number of processed deposits has not reached the limit, otherwise, stop processing.
+		if nextDepositIndex >= params.BeaconConfig().MaxPendingDepositsPerEpoch {
+			break
+		}
+
+		var isValidatorExited bool
+		var isValidatorWithdrawn bool
+		index, found := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(pendingDeposit.PublicKey))
+		if found {
+			val, err := st.ValidatorAtIndexReadOnly(index)
+			if err != nil {
+				return errors.Wrap(err, "could not get validator")
 			}
+			isValidatorExited = val.ExitEpoch() < params.BeaconConfig().FarFutureEpoch
+			isValidatorWithdrawn = val.WithdrawableEpoch() < nextEpoch
+		}
+
+		if isValidatorWithdrawn {
+			// note: the validator will never be active, just increase the balance
+			if err := helpers.IncreaseBalance(st, index, pendingDeposit.Amount); err != nil {
+				return errors.Wrap(err, "could not increase balance")
+			}
+		} else if isValidatorExited {
+			pendingDepositsToPostpone = append(pendingDepositsToPostpone, pendingDeposit)
 		} else {
-			// Validator is not exiting, attempt to process deposit.
-			if primitives.Gwei(processedAmount+balanceDeposit.Amount) > availableForProcessing {
+			isChurnLimitReached = primitives.Gwei(processedAmount+pendingDeposit.Amount) > availableForProcessing
+			if isChurnLimitReached {
 				break
 			}
-			// Deposit fits in churn, process it. Increase balance and consume churn.
-			if err := helpers.IncreaseBalance(st, balanceDeposit.Index, balanceDeposit.Amount); err != nil {
-				return err
+			processedAmount += pendingDeposit.Amount
+
+			// note: the following code deviates from the spec in order to perform batch signature verification
+			if found {
+				if err := helpers.IncreaseBalance(st, index, pendingDeposit.Amount); err != nil {
+					return errors.Wrap(err, "could not increase balance")
+				}
+			} else {
+				// Collect deposit for batch signature verification
+				pendingDepositsToBatchVerify = append(pendingDepositsToBatchVerify, pendingDeposit)
 			}
-			processedAmount += balanceDeposit.Amount
 		}

-		// Regardless of how the deposit was handled, we move on in the queue.
+		// Regardless of how the pendingDeposit was handled, we move on in the queue.
 		nextDepositIndex++
 	}

+	// Perform batch signature verification on pending deposits that require validator registration
+	if err = batchProcessNewPendingDeposits(ctx, st, pendingDepositsToBatchVerify); err != nil {
+		return errors.Wrap(err, "could not process pending deposits with new public keys")
+	}
+
 	// Combined operation:
-	// - state.pending_balance_deposits = state.pending_balance_deposits[next_deposit_index:]
-	// - state.pending_balance_deposits += deposits_to_postpone
-	// However, the number of remaining deposits must be maintained to properly update the deposit
+	// - state.pending_deposits = state.pending_deposits[next_deposit_index:]
+	// - state.pending_deposits += deposits_to_postpone
+	// However, the number of remaining deposits must be maintained to properly update the pendingDeposit
 	// balance to consume.
-	numRemainingDeposits := len(deposits[nextDepositIndex:])
-	deposits = append(deposits[nextDepositIndex:], depositsToPostpone...)
-	if err := st.SetPendingBalanceDeposits(deposits); err != nil {
+	pendingDeposits = append(pendingDeposits[nextDepositIndex:], pendingDepositsToPostpone...)
+	if err := st.SetPendingDeposits(pendingDeposits); err != nil {
+		return errors.Wrap(err, "could not set pending deposits")
+	}
+	// Accumulate churn only if the churn limit has been hit.
+	if isChurnLimitReached {
+		return st.SetDepositBalanceToConsume(availableForProcessing - primitives.Gwei(processedAmount))
+	}
+	return st.SetDepositBalanceToConsume(0)
+}
+
+// batchProcessNewPendingDeposits should only be used to process new deposits that require validator registration
+func batchProcessNewPendingDeposits(ctx context.Context, state state.BeaconState, pendingDeposits []*ethpb.PendingDeposit) error {
+	// Return early if there are no deposits to process
+	if len(pendingDeposits) == 0 {
+		return nil
+	}
+
+	// Try batch verification of all deposit signatures
+	allSignaturesVerified, err := blocks.BatchVerifyPendingDepositsSignatures(ctx, pendingDeposits)
+	if err != nil {
+		return errors.Wrap(err, "batch signature verification failed")
+	}
+
+	pubKeyMap := make(map[[48]byte]struct{}, len(pendingDeposits))
+
+	// Process each deposit individually
+	for _, pendingDeposit := range pendingDeposits {
+		_, found := pubKeyMap[bytesutil.ToBytes48(pendingDeposit.PublicKey)]
+		if !found {
+			pubKeyMap[bytesutil.ToBytes48(pendingDeposit.PublicKey)] = struct{}{}
+		}
+		validSignature := allSignaturesVerified
+
+		// If batch verification failed, check the individual deposit signature
+		if !allSignaturesVerified {
+			validSignature, err = blocks.IsValidDepositSignature(&ethpb.Deposit_Data{
+				PublicKey:             bytesutil.SafeCopyBytes(pendingDeposit.PublicKey),
+				WithdrawalCredentials: bytesutil.SafeCopyBytes(pendingDeposit.WithdrawalCredentials),
+				Amount:                pendingDeposit.Amount,
+				Signature:             bytesutil.SafeCopyBytes(pendingDeposit.Signature),
+			})
+			if err != nil {
+				return errors.Wrap(err, "individual deposit signature verification failed")
+			}
+		}
+
+		// Add validator to the registry if the signature is valid
+		if validSignature {
+			if found {
+				index, _ := state.ValidatorIndexByPubkey(bytesutil.ToBytes48(pendingDeposit.PublicKey))
+				if err := helpers.IncreaseBalance(state, index, pendingDeposit.Amount); err != nil {
+					return errors.Wrap(err, "could not increase balance")
+				}
+			} else {
+				err = AddValidatorToRegistry(state, pendingDeposit.PublicKey, pendingDeposit.WithdrawalCredentials, pendingDeposit.Amount)
+				if err != nil {
+					return errors.Wrap(err, "failed to add validator to registry")
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// ApplyPendingDeposit implements the spec definition below.
+// Note : This function is NOT used by ProcessPendingDeposits due to simplified logic for more readable batch processing
+//
+// Spec Definition:
+//
+// def apply_pending_deposit(state: BeaconState, deposit: PendingDeposit) -> None:
+//
+//	"""
+//	Applies ``deposit`` to the ``state``.
+//	"""
+//	validator_pubkeys = [v.pubkey for v in state.validators]
+//	if deposit.pubkey not in validator_pubkeys:
+//	    # Verify the deposit signature (proof of possession) which is not checked by the deposit contract
+//	    if is_valid_deposit_signature(
+//	        deposit.pubkey,
+//	        deposit.withdrawal_credentials,
+//	        deposit.amount,
+//	        deposit.signature
+//	    ):
+//	        add_validator_to_registry(state, deposit.pubkey, deposit.withdrawal_credentials, deposit.amount)
+//	else:
+//	    validator_index = ValidatorIndex(validator_pubkeys.index(deposit.pubkey))
+//	    # Increase balance
+//	    increase_balance(state, validator_index, deposit.amount)
+func ApplyPendingDeposit(ctx context.Context, st state.BeaconState, deposit *ethpb.PendingDeposit) error {
+	_, span := trace.StartSpan(ctx, "electra.ApplyPendingDeposit")
+	defer span.End()
+	index, ok := st.ValidatorIndexByPubkey(bytesutil.ToBytes48(deposit.PublicKey))
+	if !ok {
+		verified, err := blocks.IsValidDepositSignature(&ethpb.Deposit_Data{
+			PublicKey:             bytesutil.SafeCopyBytes(deposit.PublicKey),
+			WithdrawalCredentials: bytesutil.SafeCopyBytes(deposit.WithdrawalCredentials),
+			Amount:                deposit.Amount,
+			Signature:             bytesutil.SafeCopyBytes(deposit.Signature),
+		})
+		if err != nil {
+			return errors.Wrap(err, "could not verify deposit signature")
+		}
+
+		if verified {
+			if err := AddValidatorToRegistry(st, deposit.PublicKey, deposit.WithdrawalCredentials, deposit.Amount); err != nil {
+				return errors.Wrap(err, "could not add validator to registry")
+			}
+		}
+		return nil
+	}
+	return helpers.IncreaseBalance(st, index, deposit.Amount)
+}
+
+// AddValidatorToRegistry updates the beacon state with validator information
+// def add_validator_to_registry(state: BeaconState, pubkey: BLSPubkey, withdrawal_credentials: Bytes32, amount: uint64) -> None:
+//
+//	index = get_index_for_new_validator(state)
+//	validator = get_validator_from_deposit(pubkey, withdrawal_credentials, amount)  # [Modified in Electra:EIP7251]
+//	set_or_append_list(state.validators, index, validator)
+//	set_or_append_list(state.balances, index, amount)
+//	set_or_append_list(state.previous_epoch_participation, index, ParticipationFlags(0b0000_0000))
+//	set_or_append_list(state.current_epoch_participation, index, ParticipationFlags(0b0000_0000))
+//	set_or_append_list(state.inactivity_scores, index, uint64(0))
+func AddValidatorToRegistry(beaconState state.BeaconState, pubKey []byte, withdrawalCredentials []byte, amount uint64) error {
+	val, err := GetValidatorFromDeposit(pubKey, withdrawalCredentials, amount)
+	if err != nil {
+		return errors.Wrap(err, "could not get validator from deposit")
+	}
+	if err := beaconState.AppendValidator(val); err != nil {
+		return err
+	}
+	if err := beaconState.AppendBalance(amount); err != nil {
 		return err
 	}

-	if numRemainingDeposits == 0 {
-		return st.SetDepositBalanceToConsume(0)
-	} else {
-		return st.SetDepositBalanceToConsume(availableForProcessing - primitives.Gwei(processedAmount))
+	// only active in altair and only when it's a new validator (after append balance)
+	if beaconState.Version() >= version.Altair {
+		if err := beaconState.AppendInactivityScore(0); err != nil {
+			return err
+		}
+		if err := beaconState.AppendPreviousParticipationBits(0); err != nil {
+			return err
+		}
+		if err := beaconState.AppendCurrentParticipationBits(0); err != nil {
+			return err
+		}
 	}
+	return nil
+}
+
+// GetValidatorFromDeposit gets a new validator object with provided parameters
+//
+// def get_validator_from_deposit(pubkey: BLSPubkey, withdrawal_credentials: Bytes32, amount: uint64) -> Validator:
+//
+//	validator = Validator(
+//	    pubkey=pubkey,
+//	    withdrawal_credentials=withdrawal_credentials,
+//	    effective_balance=Gwei(0),
+//	    slashed=False,
+//	    activation_eligibility_epoch=FAR_FUTURE_EPOCH,
+//	    activation_epoch=FAR_FUTURE_EPOCH,
+//	    exit_epoch=FAR_FUTURE_EPOCH,
+//	    withdrawable_epoch=FAR_FUTURE_EPOCH,
+//	)
+//
+//	# [Modified in Electra:EIP7251]
+//	max_effective_balance = get_max_effective_balance(validator)
+//	validator.effective_balance = min(amount - amount % EFFECTIVE_BALANCE_INCREMENT, max_effective_balance)
+//
+//	return validator
+func GetValidatorFromDeposit(pubKey []byte, withdrawalCredentials []byte, amount uint64) (*ethpb.Validator, error) {
+	validator := &ethpb.Validator{
+		PublicKey:                  pubKey,
+		WithdrawalCredentials:      withdrawalCredentials,
+		EffectiveBalance:           0,
+		Slashed:                    false,
+		ActivationEligibilityEpoch: params.BeaconConfig().FarFutureEpoch,
+		ActivationEpoch:            params.BeaconConfig().FarFutureEpoch,
+		ExitEpoch:                  params.BeaconConfig().FarFutureEpoch,
+		WithdrawableEpoch:          params.BeaconConfig().FarFutureEpoch,
+	}
+	v, err := state_native.NewValidator(validator)
+	if err != nil {
+		return nil, err
+	}
+	maxEffectiveBalance := helpers.ValidatorMaxEffectiveBalance(v)
+	validator.EffectiveBalance = min(amount-(amount%params.BeaconConfig().EffectiveBalanceIncrement), maxEffectiveBalance)
+	return validator, nil
 }

 // ProcessDepositRequests is a function as part of electra to process execution layer deposits
 func ProcessDepositRequests(ctx context.Context, beaconState state.BeaconState, requests []*enginev1.DepositRequest) (state.BeaconState, error) {
-	ctx, span := trace.StartSpan(ctx, "electra.ProcessDepositRequests")
+	_, span := trace.StartSpan(ctx, "electra.ProcessDepositRequests")
 	defer span.End()

 	if len(requests) == 0 {
 		return beaconState, nil
 	}

-	deposits := make([]*ethpb.Deposit, 0)
-	for _, req := range requests {
-		if req == nil {
-			return nil, errors.New("got a nil DepositRequest")
-		}
-		deposits = append(deposits, &ethpb.Deposit{
-			Data: &ethpb.Deposit_Data{
-				PublicKey:             req.Pubkey,
-				WithdrawalCredentials: req.WithdrawalCredentials,
-				Amount:                req.Amount,
-				Signature:             req.Signature,
-			},
-		})
-	}
-	batchVerified, err := blocks.BatchVerifyDepositsSignatures(ctx, deposits)
-	if err != nil {
-		return nil, errors.Wrap(err, "could not verify deposit signatures in batch")
-	}
+	var err error
 	for _, receipt := range requests {
-		beaconState, err = processDepositRequest(beaconState, receipt, batchVerified)
+		beaconState, err = processDepositRequest(beaconState, receipt)
 		if err != nil {
 			return nil, errors.Wrap(err, "could not apply deposit request")
 		}
@@ -338,34 +572,42 @@ func ProcessDepositRequests(ctx context.Context, beaconState state.BeaconState,
 	return beaconState, nil
 }

-// processDepositRequest processes the specific deposit receipt
+// processDepositRequest processes the specific deposit request
 // def process_deposit_request(state: BeaconState, deposit_request: DepositRequest) -> None:
 //
 //	# Set deposit request start index
-//	if state.deposit_requests_start_index == UNSET_DEPOSIT_REQUEST_START_INDEX:
+//	if state.deposit_requests_start_index == UNSET_DEPOSIT_REQUESTS_START_INDEX:
 //	    state.deposit_requests_start_index = deposit_request.index
 //
-//	apply_deposit(
-//	    state=state,
+//	# Create pending deposit
+//	state.pending_deposits.append(PendingDeposit(
 //	    pubkey=deposit_request.pubkey,
 //	    withdrawal_credentials=deposit_request.withdrawal_credentials,
 //	    amount=deposit_request.amount,
 //	    signature=deposit_request.signature,
-//	)
-func processDepositRequest(beaconState state.BeaconState, request *enginev1.DepositRequest, verifySignature bool) (state.BeaconState, error) {
+//	    slot=state.slot,
+//	))
+func processDepositRequest(beaconState state.BeaconState, request *enginev1.DepositRequest) (state.BeaconState, error) {
 	requestsStartIndex, err := beaconState.DepositRequestsStartIndex()
 	if err != nil {
 		return nil, errors.Wrap(err, "could not get deposit requests start index")
 	}
 	if requestsStartIndex == params.BeaconConfig().UnsetDepositRequestsStartIndex {
+		if request == nil {
+			return nil, errors.New("nil deposit request")
+		}
 		if err := beaconState.SetDepositRequestsStartIndex(request.Index); err != nil {
 			return nil, errors.Wrap(err, "could not set deposit requests start index")
 		}
 	}
-	return ApplyDeposit(beaconState, &ethpb.Deposit_Data{
+	if err := beaconState.AppendPendingDeposit(&ethpb.PendingDeposit{
 		PublicKey:             bytesutil.SafeCopyBytes(request.Pubkey),
-		Amount:                request.Amount,
 		WithdrawalCredentials: bytesutil.SafeCopyBytes(request.WithdrawalCredentials),
+		Amount:                request.Amount,
 		Signature:             bytesutil.SafeCopyBytes(request.Signature),
-	}, verifySignature)
+		Slot:                  beaconState.Slot(),
+	}); err != nil {
+		return nil, errors.Wrap(err, "could not append deposit request")
+	}
+	return beaconState, nil
 }
--- a/beacon-chain/core/electra/deposits_test.go
+++ b/beacon-chain/core/electra/deposits_test.go
@@ -9,10 +9,12 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/signing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
+	stateTesting "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/testing"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/crypto/bls"
+	"github.com/prysmaticlabs/prysm/v5/crypto/bls/common"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
@@ -20,7 +22,41 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/testing/util"
 )

-func TestProcessPendingBalanceDeposits(t *testing.T) {
+func TestProcessPendingDepositsMultiplesSameDeposits(t *testing.T) {
+	st := stateWithActiveBalanceETH(t, 1000)
+	deps := make([]*eth.PendingDeposit, 2) // Make same deposit twice
+	validators := st.Validators()
+	sk, err := bls.RandKey()
+	require.NoError(t, err)
+	for i := 0; i < len(deps); i += 1 {
+		wc := make([]byte, 32)
+		wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+		wc[31] = byte(i)
+		validators[i].PublicKey = sk.PublicKey().Marshal()
+		validators[i].WithdrawalCredentials = wc
+		deps[i] = stateTesting.GeneratePendingDeposit(t, sk, 32, bytesutil.ToBytes32(wc), 0)
+	}
+	require.NoError(t, st.SetPendingDeposits(deps))
+
+	err = electra.ProcessPendingDeposits(context.TODO(), st, 10000)
+	require.NoError(t, err)
+
+	val := st.Validators()
+	seenPubkeys := make(map[string]struct{})
+	for i := 0; i < len(val); i += 1 {
+		if len(val[i].PublicKey) == 0 {
+			continue
+		}
+		_, ok := seenPubkeys[string(val[i].PublicKey)]
+		if ok {
+			t.Fatalf("duplicated pubkeys")
+		} else {
+			seenPubkeys[string(val[i].PublicKey)] = struct{}{}
+		}
+	}
+}
+
+func TestProcessPendingDeposits(t *testing.T) {
 	tests := []struct {
 		name    string
 		state   state.BeaconState
@@ -48,17 +84,10 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 		{
 			name: "more deposits than balance to consume processes partial deposits",
 			state: func() state.BeaconState {
-				st := stateWithActiveBalanceETH(t, 1_000)
-				require.NoError(t, st.SetDepositBalanceToConsume(100))
 				amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
-				deps := make([]*eth.PendingBalanceDeposit, 20)
-				for i := 0; i < len(deps); i += 1 {
-					deps[i] = &eth.PendingBalanceDeposit{
-						Amount: uint64(amountAvailForProcessing) / 10,
-						Index:  primitives.ValidatorIndex(i),
-					}
-				}
-				require.NoError(t, st.SetPendingBalanceDeposits(deps))
+				depositAmount := uint64(amountAvailForProcessing) / 10
+				st := stateWithPendingDeposits(t, 1_000, 20, depositAmount)
+				require.NoError(t, st.SetDepositBalanceToConsume(100))
 				return st
 			}(),
 			check: func(t *testing.T, st state.BeaconState) {
@@ -74,25 +103,45 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 				}

 				// Half of the balance deposits should have been processed.
-				remaining, err := st.PendingBalanceDeposits()
+				remaining, err := st.PendingDeposits()
 				require.NoError(t, err)
 				require.Equal(t, 10, len(remaining))
 			},
 		},
+		{
+			name: "withdrawn validators should not consume churn",
+			state: func() state.BeaconState {
+				amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
+				depositAmount := uint64(amountAvailForProcessing)
+				// set the pending deposits to the maximum churn limit
+				st := stateWithPendingDeposits(t, 1_000, 2, depositAmount)
+				vals := st.Validators()
+				vals[1].WithdrawableEpoch = 0
+				require.NoError(t, st.SetValidators(vals))
+				return st
+			}(),
+			check: func(t *testing.T, st state.BeaconState) {
+				amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
+				// Validators 0..9 should have their balance increased
+				for i := primitives.ValidatorIndex(0); i < 2; i++ {
+					b, err := st.BalanceAtIndex(i)
+					require.NoError(t, err)
+					require.Equal(t, params.BeaconConfig().MinActivationBalance+uint64(amountAvailForProcessing), b)
+				}
+
+				// All pending deposits should have been processed
+				remaining, err := st.PendingDeposits()
+				require.NoError(t, err)
+				require.Equal(t, 0, len(remaining))
+			},
+		},
 		{
 			name: "less deposits than balance to consume processes all deposits",
 			state: func() state.BeaconState {
-				st := stateWithActiveBalanceETH(t, 1_000)
-				require.NoError(t, st.SetDepositBalanceToConsume(0))
 				amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
-				deps := make([]*eth.PendingBalanceDeposit, 5)
-				for i := 0; i < len(deps); i += 1 {
-					deps[i] = &eth.PendingBalanceDeposit{
-						Amount: uint64(amountAvailForProcessing) / 5,
-						Index:  primitives.ValidatorIndex(i),
-					}
-				}
-				require.NoError(t, st.SetPendingBalanceDeposits(deps))
+				depositAmount := uint64(amountAvailForProcessing) / 5
+				st := stateWithPendingDeposits(t, 1_000, 5, depositAmount)
+				require.NoError(t, st.SetDepositBalanceToConsume(0))
 				return st
 			}(),
 			check: func(t *testing.T, st state.BeaconState) {
@@ -108,7 +157,73 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 				}

 				// All of the balance deposits should have been processed.
-				remaining, err := st.PendingBalanceDeposits()
+				remaining, err := st.PendingDeposits()
+				require.NoError(t, err)
+				require.Equal(t, 0, len(remaining))
+			},
+		},
+		{
+			name: "process pending deposit for unknown key, activates new key",
+			state: func() state.BeaconState {
+				st := stateWithActiveBalanceETH(t, 0)
+				sk, err := bls.RandKey()
+				require.NoError(t, err)
+				wc := make([]byte, 32)
+				wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+				wc[31] = byte(0)
+				dep := stateTesting.GeneratePendingDeposit(t, sk, params.BeaconConfig().MinActivationBalance, bytesutil.ToBytes32(wc), 0)
+				require.NoError(t, st.SetPendingDeposits([]*eth.PendingDeposit{dep}))
+				require.Equal(t, 0, len(st.Validators()))
+				require.Equal(t, 0, len(st.Balances()))
+				return st
+			}(),
+			check: func(t *testing.T, st state.BeaconState) {
+				res, err := st.DepositBalanceToConsume()
+				require.NoError(t, err)
+				require.Equal(t, primitives.Gwei(0), res)
+				b, err := st.BalanceAtIndex(0)
+				require.NoError(t, err)
+				require.Equal(t, params.BeaconConfig().MinActivationBalance, b)
+
+				// All of the balance deposits should have been processed.
+				remaining, err := st.PendingDeposits()
+				require.NoError(t, err)
+				require.Equal(t, 0, len(remaining))
+
+				// validator becomes active
+				require.Equal(t, 1, len(st.Validators()))
+				require.Equal(t, 1, len(st.Balances()))
+			},
+		},
+		{
+			name: "process excess balance that uses a point to infinity signature, processed as a topup",
+			state: func() state.BeaconState {
+				excessBalance := uint64(100)
+				st := stateWithActiveBalanceETH(t, 32)
+				validators := st.Validators()
+				sk, err := bls.RandKey()
+				require.NoError(t, err)
+				wc := make([]byte, 32)
+				wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+				wc[31] = byte(0)
+				validators[0].PublicKey = sk.PublicKey().Marshal()
+				validators[0].WithdrawalCredentials = wc
+				dep := stateTesting.GeneratePendingDeposit(t, sk, excessBalance, bytesutil.ToBytes32(wc), 0)
+				dep.Signature = common.InfiniteSignature[:]
+				require.NoError(t, st.SetValidators(validators))
+				require.NoError(t, st.SetPendingDeposits([]*eth.PendingDeposit{dep}))
+				return st
+			}(),
+			check: func(t *testing.T, st state.BeaconState) {
+				res, err := st.DepositBalanceToConsume()
+				require.NoError(t, err)
+				require.Equal(t, primitives.Gwei(0), res)
+				b, err := st.BalanceAtIndex(0)
+				require.NoError(t, err)
+				require.Equal(t, params.BeaconConfig().MinActivationBalance+uint64(100), b)
+
+				// All of the balance deposits should have been processed.
+				remaining, err := st.PendingDeposits()
 				require.NoError(t, err)
 				require.Equal(t, 0, len(remaining))
 			},
@@ -116,17 +231,10 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 		{
 			name: "exiting validator deposit postponed",
 			state: func() state.BeaconState {
-				st := stateWithActiveBalanceETH(t, 1_000)
-				require.NoError(t, st.SetDepositBalanceToConsume(0))
 				amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
-				deps := make([]*eth.PendingBalanceDeposit, 5)
-				for i := 0; i < len(deps); i += 1 {
-					deps[i] = &eth.PendingBalanceDeposit{
-						Amount: uint64(amountAvailForProcessing) / 5,
-						Index:  primitives.ValidatorIndex(i),
-					}
-				}
-				require.NoError(t, st.SetPendingBalanceDeposits(deps))
+				depositAmount := uint64(amountAvailForProcessing) / 5
+				st := stateWithPendingDeposits(t, 1_000, 5, depositAmount)
+				require.NoError(t, st.SetDepositBalanceToConsume(0))
 				v, err := st.ValidatorAtIndex(0)
 				require.NoError(t, err)
 				v.ExitEpoch = 10
@@ -148,7 +256,7 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {

 				// All of the balance deposits should have been processed, except validator index 0 was
 				// added back to the pending deposits queue.
-				remaining, err := st.PendingBalanceDeposits()
+				remaining, err := st.PendingDeposits()
 				require.NoError(t, err)
 				require.Equal(t, 1, len(remaining))
 			},
@@ -156,15 +264,7 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 		{
 			name: "exited validator balance increased",
 			state: func() state.BeaconState {
-				st := stateWithActiveBalanceETH(t, 1_000)
-				deps := make([]*eth.PendingBalanceDeposit, 1)
-				for i := 0; i < len(deps); i += 1 {
-					deps[i] = &eth.PendingBalanceDeposit{
-						Amount: 1_000_000,
-						Index:  primitives.ValidatorIndex(i),
-					}
-				}
-				require.NoError(t, st.SetPendingBalanceDeposits(deps))
+				st := stateWithPendingDeposits(t, 1_000, 1, 1_000_000)
 				v, err := st.ValidatorAtIndex(0)
 				require.NoError(t, err)
 				v.ExitEpoch = 2
@@ -182,7 +282,7 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 				require.Equal(t, uint64(1_100_000), b)

 				// All of the balance deposits should have been processed.
-				remaining, err := st.PendingBalanceDeposits()
+				remaining, err := st.PendingDeposits()
 				require.NoError(t, err)
 				require.Equal(t, 0, len(remaining))
 			},
@@ -199,7 +299,7 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 				tab, err = helpers.TotalActiveBalance(tt.state)
 			}
 			require.NoError(t, err)
-			err = electra.ProcessPendingBalanceDeposits(context.TODO(), tt.state, primitives.Gwei(tab))
+			err = electra.ProcessPendingDeposits(context.TODO(), tt.state, primitives.Gwei(tab))
 			require.Equal(t, tt.wantErr, err != nil, "wantErr=%v, got err=%s", tt.wantErr, err)
 			if tt.check != nil {
 				tt.check(t, tt.state)
@@ -208,6 +308,27 @@ func TestProcessPendingBalanceDeposits(t *testing.T) {
 	}
 }

+func TestBatchProcessNewPendingDeposits(t *testing.T) {
+	t.Run("invalid batch initiates correct individual validation", func(t *testing.T) {
+		st := stateWithActiveBalanceETH(t, 0)
+		require.Equal(t, 0, len(st.Validators()))
+		require.Equal(t, 0, len(st.Balances()))
+		sk, err := bls.RandKey()
+		require.NoError(t, err)
+		wc := make([]byte, 32)
+		wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+		wc[31] = byte(0)
+		validDep := stateTesting.GeneratePendingDeposit(t, sk, params.BeaconConfig().MinActivationBalance, bytesutil.ToBytes32(wc), 0)
+		invalidDep := &eth.PendingDeposit{PublicKey: make([]byte, 48)}
+		// have a combination of valid and invalid deposits
+		deps := []*eth.PendingDeposit{validDep, invalidDep}
+		require.NoError(t, electra.BatchProcessNewPendingDeposits(context.Background(), st, deps))
+		// successfully added to register
+		require.Equal(t, 1, len(st.Validators()))
+		require.Equal(t, 1, len(st.Balances()))
+	})
+}
+
 func TestProcessDepositRequests(t *testing.T) {
 	st, _ := util.DeterministicGenesisStateElectra(t, 1)
 	sk, err := bls.RandKey()
@@ -220,7 +341,7 @@ func TestProcessDepositRequests(t *testing.T) {
 	})
 	t.Run("nil request errors", func(t *testing.T) {
 		_, err = electra.ProcessDepositRequests(context.Background(), st, []*enginev1.DepositRequest{nil})
-		require.ErrorContains(t, "got a nil DepositRequest", err)
+		require.ErrorContains(t, "nil deposit request", err)
 	})

 	vals := st.Validators()
@@ -230,7 +351,7 @@ func TestProcessDepositRequests(t *testing.T) {
 	bals := st.Balances()
 	bals[0] = params.BeaconConfig().MinActivationBalance + 2000
 	require.NoError(t, st.SetBalances(bals))
-	require.NoError(t, st.SetPendingBalanceDeposits(make([]*eth.PendingBalanceDeposit, 0))) // reset pbd as the determinitstic state populates this already
+	require.NoError(t, st.SetPendingDeposits(make([]*eth.PendingDeposit, 0))) // reset pbd as the determinitstic state populates this already
 	withdrawalCred := make([]byte, 32)
 	withdrawalCred[0] = params.BeaconConfig().CompoundingWithdrawalPrefixByte
 	depositMessage := &eth.DepositMessage{
@@ -255,11 +376,10 @@ func TestProcessDepositRequests(t *testing.T) {
 	st, err = electra.ProcessDepositRequests(context.Background(), st, requests)
 	require.NoError(t, err)

-	pbd, err := st.PendingBalanceDeposits()
+	pbd, err := st.PendingDeposits()
 	require.NoError(t, err)
-	require.Equal(t, 2, len(pbd))
+	require.Equal(t, 1, len(pbd))
 	require.Equal(t, uint64(1000), pbd[0].Amount)
-	require.Equal(t, uint64(2000), pbd[1].Amount)
 }

 func TestProcessDeposit_Electra_Simple(t *testing.T) {
@@ -286,7 +406,7 @@ func TestProcessDeposit_Electra_Simple(t *testing.T) {
 	require.NoError(t, err)
 	pdSt, err := electra.ProcessDeposits(context.Background(), st, deps)
 	require.NoError(t, err)
-	pbd, err := pdSt.PendingBalanceDeposits()
+	pbd, err := pdSt.PendingDeposits()
 	require.NoError(t, err)
 	require.Equal(t, params.BeaconConfig().MinActivationBalance, pbd[2].Amount)
 	require.Equal(t, 3, len(pbd))
@@ -322,7 +442,7 @@ func TestProcessDeposit_SkipsInvalidDeposit(t *testing.T) {
 		},
 	})
 	require.NoError(t, err)
-	newState, err := electra.ProcessDeposit(beaconState, dep[0], true)
+	newState, err := electra.ProcessDeposit(beaconState, dep[0], false)
 	require.NoError(t, err, "Expected invalid block deposit to be ignored without error")

 	if newState.Eth1DepositIndex() != 1 {
@@ -359,42 +479,128 @@ func TestApplyDeposit_TopUps_WithBadSignature(t *testing.T) {
 	vals[0].PublicKey = sk.PublicKey().Marshal()
 	vals[0].WithdrawalCredentials[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
 	require.NoError(t, st.SetValidators(vals))
-	adSt, err := electra.ApplyDeposit(st, depositData, true)
+	adSt, err := electra.ApplyDeposit(st, depositData, false)
 	require.NoError(t, err)
-	pbd, err := adSt.PendingBalanceDeposits()
+	pbd, err := adSt.PendingDeposits()
 	require.NoError(t, err)
 	require.Equal(t, 1, len(pbd))
 	require.Equal(t, topUpAmount, pbd[0].Amount)
 }

-func TestApplyDeposit_Electra_SwitchToCompoundingValidator(t *testing.T) {
-	st, _ := util.DeterministicGenesisStateElectra(t, 3)
+// stateWithActiveBalanceETH generates a mock beacon state given a balance in eth
+func stateWithActiveBalanceETH(t *testing.T, balETH uint64) state.BeaconState {
+	gwei := balETH * 1_000_000_000
+	balPerVal := params.BeaconConfig().MinActivationBalance
+	numVals := gwei / balPerVal
+
+	vals := make([]*eth.Validator, numVals)
+	bals := make([]uint64, numVals)
+	for i := uint64(0); i < numVals; i++ {
+		wc := make([]byte, 32)
+		wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+		wc[31] = byte(i)
+		vals[i] = &eth.Validator{
+			ActivationEpoch:       0,
+			ExitEpoch:             params.BeaconConfig().FarFutureEpoch,
+			EffectiveBalance:      balPerVal,
+			WithdrawalCredentials: wc,
+			WithdrawableEpoch:     params.BeaconConfig().FarFutureEpoch,
+		}
+		bals[i] = balPerVal
+	}
+	st, err := state_native.InitializeFromProtoUnsafeElectra(&eth.BeaconStateElectra{
+		Slot:       10 * params.BeaconConfig().SlotsPerEpoch,
+		Validators: vals,
+		Balances:   bals,
+		Fork: &eth.Fork{
+			CurrentVersion: params.BeaconConfig().ElectraForkVersion,
+		},
+	})
+	require.NoError(t, err)
+	// set some fake finalized checkpoint
+	require.NoError(t, st.SetFinalizedCheckpoint(&eth.Checkpoint{
+		Epoch: 0,
+		Root:  make([]byte, 32),
+	}))
+	return st
+}
+
+// stateWithPendingDeposits with pending deposits and existing ethbalance
+func stateWithPendingDeposits(t *testing.T, balETH uint64, numDeposits, amount uint64) state.BeaconState {
+	st := stateWithActiveBalanceETH(t, balETH)
+	deps := make([]*eth.PendingDeposit, numDeposits)
+	validators := st.Validators()
+	for i := 0; i < len(deps); i += 1 {
+		sk, err := bls.RandKey()
+		require.NoError(t, err)
+		wc := make([]byte, 32)
+		wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+		wc[31] = byte(i)
+		validators[i].PublicKey = sk.PublicKey().Marshal()
+		validators[i].WithdrawalCredentials = wc
+		deps[i] = stateTesting.GeneratePendingDeposit(t, sk, amount, bytesutil.ToBytes32(wc), 0)
+	}
+	require.NoError(t, st.SetValidators(validators))
+	require.NoError(t, st.SetPendingDeposits(deps))
+	return st
+}
+
+func TestApplyPendingDeposit_TopUp(t *testing.T) {
+	excessBalance := uint64(100)
+	st := stateWithActiveBalanceETH(t, 32)
+	validators := st.Validators()
 	sk, err := bls.RandKey()
 	require.NoError(t, err)
-	withdrawalCred := make([]byte, 32)
-	withdrawalCred[0] = params.BeaconConfig().CompoundingWithdrawalPrefixByte
-	depositData := &eth.Deposit_Data{
-		PublicKey:             sk.PublicKey().Marshal(),
-		Amount:                1000,
-		WithdrawalCredentials: withdrawalCred,
-		Signature:             make([]byte, fieldparams.BLSSignatureLength),
-	}
-	vals := st.Validators()
-	vals[0].PublicKey = sk.PublicKey().Marshal()
-	vals[0].WithdrawalCredentials[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
-	require.NoError(t, st.SetValidators(vals))
-	bals := st.Balances()
-	bals[0] = params.BeaconConfig().MinActivationBalance + 2000
-	require.NoError(t, st.SetBalances(bals))
-	sr, err := signing.ComputeSigningRoot(depositData, bytesutil.ToBytes(3, 32))
+	wc := make([]byte, 32)
+	wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+	wc[31] = byte(0)
+	validators[0].PublicKey = sk.PublicKey().Marshal()
+	validators[0].WithdrawalCredentials = wc
+	dep := stateTesting.GeneratePendingDeposit(t, sk, excessBalance, bytesutil.ToBytes32(wc), 0)
+	dep.Signature = common.InfiniteSignature[:]
+	require.NoError(t, st.SetValidators(validators))
+
+	require.NoError(t, electra.ApplyPendingDeposit(context.Background(), st, dep))
+
+	b, err := st.BalanceAtIndex(0)
 	require.NoError(t, err)
-	sig := sk.Sign(sr[:])
-	depositData.Signature = sig.Marshal()
-	adSt, err := electra.ApplyDeposit(st, depositData, false)
-	require.NoError(t, err)
-	pbd, err := adSt.PendingBalanceDeposits()
-	require.NoError(t, err)
-	require.Equal(t, 2, len(pbd))
-	require.Equal(t, uint64(1000), pbd[0].Amount)
-	require.Equal(t, uint64(2000), pbd[1].Amount)
+	require.Equal(t, params.BeaconConfig().MinActivationBalance+uint64(excessBalance), b)
+}
+
+func TestApplyPendingDeposit_UnknownKey(t *testing.T) {
+	st := stateWithActiveBalanceETH(t, 0)
+	sk, err := bls.RandKey()
+	require.NoError(t, err)
+	wc := make([]byte, 32)
+	wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+	wc[31] = byte(0)
+	dep := stateTesting.GeneratePendingDeposit(t, sk, params.BeaconConfig().MinActivationBalance, bytesutil.ToBytes32(wc), 0)
+	require.Equal(t, 0, len(st.Validators()))
+	require.NoError(t, electra.ApplyPendingDeposit(context.Background(), st, dep))
+	// activates new validator
+	require.Equal(t, 1, len(st.Validators()))
+	b, err := st.BalanceAtIndex(0)
+	require.NoError(t, err)
+	require.Equal(t, params.BeaconConfig().MinActivationBalance, b)
+}
+
+func TestApplyPendingDeposit_InvalidSignature(t *testing.T) {
+	st := stateWithActiveBalanceETH(t, 0)
+
+	sk, err := bls.RandKey()
+	require.NoError(t, err)
+	wc := make([]byte, 32)
+	wc[0] = params.BeaconConfig().ETH1AddressWithdrawalPrefixByte
+	wc[31] = byte(0)
+	dep := &eth.PendingDeposit{
+		PublicKey:             sk.PublicKey().Marshal(),
+		WithdrawalCredentials: wc,
+		Amount:                100,
+	}
+	require.Equal(t, 0, len(st.Validators()))
+	require.NoError(t, electra.ApplyPendingDeposit(context.Background(), st, dep))
+	// no validator added
+	require.Equal(t, 0, len(st.Validators()))
+	// no topup either
+	require.Equal(t, 0, len(st.Balances()))
 }
--- a/beacon-chain/core/electra/export_test.go
+++ b/beacon-chain/core/electra/export_test.go
@@ -0,0 +1,3 @@
+package electra
+
+var BatchProcessNewPendingDeposits = batchProcessNewPendingDeposits
--- a/beacon-chain/core/electra/registry_updates.go
+++ b/beacon-chain/core/electra/registry_updates.go
@@ -18,23 +18,24 @@ import (
 //
 // Spec pseudocode definition:
 //
-//		def process_registry_updates(state: BeaconState) -> None:
-//		    # Process activation eligibility and ejections
-//		    for index, validator in enumerate(state.validators):
-//		        if is_eligible_for_activation_queue(validator):
-//		            validator.activation_eligibility_epoch = get_current_epoch(state) + 1
+//	def process_registry_updates(state: BeaconState) -> None:
+//	    # Process activation eligibility and ejections
+//	    for index, validator in enumerate(state.validators):
+//	        if is_eligible_for_activation_queue(validator):  # [Modified in Electra:EIP7251]
+//	            validator.activation_eligibility_epoch = get_current_epoch(state) + 1
 //
-//		        if (
-//		            is_active_validator(validator, get_current_epoch(state))
-//		            and validator.effective_balance <= EJECTION_BALANCE
-//		        ):
-//		            initiate_validator_exit(state, ValidatorIndex(index))
+//	        if (
+//	            is_active_validator(validator, get_current_epoch(state))
+//	            and validator.effective_balance <= EJECTION_BALANCE
+//	        ):
+//	            initiate_validator_exit(state, ValidatorIndex(index))  # [Modified in Electra:EIP7251]
 //
-//	         # Activate all eligible validators
-//	         activation_epoch = compute_activation_exit_epoch(get_current_epoch(state))
-//	         for validator in state.validators:
-//	             if is_eligible_for_activation(state, validator):
-//	                 validator.activation_epoch = activation_epoch
+//	    # Activate all eligible validators
+//	    # [Modified in Electra:EIP7251]
+//	    activation_epoch = compute_activation_exit_epoch(get_current_epoch(state))
+//	    for validator in state.validators:
+//	        if is_eligible_for_activation(state, validator):
+//	            validator.activation_epoch = activation_epoch
 func ProcessRegistryUpdates(ctx context.Context, st state.BeaconState) error {
 	currentEpoch := time.CurrentEpoch(st)
 	ejectionBal := params.BeaconConfig().EjectionBalance
@@ -90,8 +91,8 @@ func ProcessRegistryUpdates(ctx context.Context, st state.BeaconState) error {
 		}
 	}

+	// Activate all eligible validators.
 	for _, idx := range eligibleForActivation {
-		// Activate all eligible validators.
 		v, err := st.ValidatorAtIndex(idx)
 		if err != nil {
 			return err
--- a/beacon-chain/core/electra/transition.go
+++ b/beacon-chain/core/electra/transition.go
@@ -29,7 +29,6 @@ var (
 	ProcessParticipationFlagUpdates      = altair.ProcessParticipationFlagUpdates
 	ProcessSyncCommitteeUpdates          = altair.ProcessSyncCommitteeUpdates
 	AttestationsDelta                    = altair.AttestationsDelta
-	ProcessSyncAggregate                 = altair.ProcessSyncAggregate
 )

 // ProcessEpoch describes the per epoch operations that are performed on the beacon state.
@@ -41,14 +40,17 @@ var (
 //	    process_justification_and_finalization(state)
 //	    process_inactivity_updates(state)
 //	    process_rewards_and_penalties(state)
-//	    process_registry_updates(state)
-//	    process_slashings(state)
+//	    process_registry_updates(state)  # [Modified in Electra:EIP7251]
+//	    process_slashings(state)  # [Modified in Electra:EIP7251]
 //	    process_eth1_data_reset(state)
-//	    process_pending_balance_deposits(state)  # New in EIP7251
-//	    process_pending_consolidations(state)  # New in EIP7251
-//	    process_effective_balance_updates(state)
+//	    process_pending_deposits(state)  # [New in Electra:EIP7251]
+//	    process_pending_consolidations(state)  # [New in Electra:EIP7251]
+//	    process_effective_balance_updates(state)  # [Modified in Electra:EIP7251]
 //	    process_slashings_reset(state)
 //	    process_randao_mixes_reset(state)
+//	    process_historical_summaries_update(state)
+//	    process_participation_flag_updates(state)
+//	    process_sync_committee_updates(state)
 func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
 	_, span := trace.StartSpan(ctx, "electra.ProcessEpoch")
 	defer span.End()
@@ -76,25 +78,17 @@ func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
 	if err != nil {
 		return errors.Wrap(err, "could not process rewards and penalties")
 	}
-
 	if err := ProcessRegistryUpdates(ctx, state); err != nil {
 		return errors.Wrap(err, "could not process registry updates")
 	}
-
-	proportionalSlashingMultiplier, err := state.ProportionalSlashingMultiplier()
-	if err != nil {
-		return err
-	}
-	state, err = ProcessSlashings(state, proportionalSlashingMultiplier)
-	if err != nil {
+	if err := ProcessSlashings(state); err != nil {
 		return err
 	}
 	state, err = ProcessEth1DataReset(state)
 	if err != nil {
 		return err
 	}
-
-	if err = ProcessPendingBalanceDeposits(ctx, state, primitives.Gwei(bp.ActiveCurrentEpoch)); err != nil {
+	if err = ProcessPendingDeposits(ctx, state, primitives.Gwei(bp.ActiveCurrentEpoch)); err != nil {
 		return err
 	}
 	if err = ProcessPendingConsolidations(ctx, state); err != nil {
@@ -103,7 +97,6 @@ func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
 	if err = ProcessEffectiveBalanceUpdates(state); err != nil {
 		return err
 	}
-
 	state, err = ProcessSlashingsReset(state)
 	if err != nil {
 		return err
@@ -116,17 +109,14 @@ func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
 	if err != nil {
 		return err
 	}
-
 	state, err = ProcessParticipationFlagUpdates(state)
 	if err != nil {
 		return err
 	}
-
 	_, err = ProcessSyncCommitteeUpdates(ctx, state)
 	if err != nil {
 		return err
 	}
-
 	return nil
 }

--- a/beacon-chain/core/electra/transition_no_verify_sig.go
+++ b/beacon-chain/core/electra/transition_no_verify_sig.go
@@ -78,23 +78,19 @@ func ProcessOperations(
 		return nil, errors.Wrap(err, "could not process bls-to-execution changes")
 	}
 	// new in electra
-	e, err := bb.Execution()
+	requests, err := bb.ExecutionRequests()
 	if err != nil {
-		return nil, errors.Wrap(err, "could not get execution data from block")
+		return nil, errors.Wrap(err, "could not get execution requests")
 	}
-	exe, ok := e.(interfaces.ExecutionDataElectra)
-	if !ok {
-		return nil, errors.New("could not cast execution data to electra execution data")
-	}
-	st, err = ProcessDepositRequests(ctx, st, exe.DepositRequests())
+	st, err = ProcessDepositRequests(ctx, st, requests.Deposits)
 	if err != nil {
-		return nil, errors.Wrap(err, "could not process deposit receipts")
+		return nil, errors.Wrap(err, "could not process deposit requests")
 	}
-	st, err = ProcessWithdrawalRequests(ctx, st, exe.WithdrawalRequests())
+	st, err = ProcessWithdrawalRequests(ctx, st, requests.Withdrawals)
 	if err != nil {
-		return nil, errors.Wrap(err, "could not process execution layer withdrawal requests")
+		return nil, errors.Wrap(err, "could not process withdrawal requests")
 	}
-	if err := ProcessConsolidationRequests(ctx, st, exe.ConsolidationRequests()); err != nil {
+	if err := ProcessConsolidationRequests(ctx, st, requests.Consolidations); err != nil {
 		return nil, fmt.Errorf("could not process consolidation requests: %w", err)
 	}
 	return st, nil
--- a/beacon-chain/core/electra/transition_test.go
+++ b/beacon-chain/core/electra/transition_test.go
@@ -57,14 +57,17 @@ func TestProcessEpoch_CanProcessElectra(t *testing.T) {
 	require.NoError(t, st.SetSlot(10*params.BeaconConfig().SlotsPerEpoch))
 	require.NoError(t, st.SetDepositBalanceToConsume(100))
 	amountAvailForProcessing := helpers.ActivationExitChurnLimit(1_000 * 1e9)
-	deps := make([]*ethpb.PendingBalanceDeposit, 20)
+	validators := st.Validators()
+	deps := make([]*ethpb.PendingDeposit, 20)
 	for i := 0; i < len(deps); i += 1 {
-		deps[i] = &ethpb.PendingBalanceDeposit{
-			Amount: uint64(amountAvailForProcessing) / 10,
-			Index:  primitives.ValidatorIndex(i),
+		deps[i] = &ethpb.PendingDeposit{
+			PublicKey:             validators[i].PublicKey,
+			WithdrawalCredentials: validators[i].WithdrawalCredentials,
+			Amount:                uint64(amountAvailForProcessing) / 10,
+			Slot:                  0,
 		}
 	}
-	require.NoError(t, st.SetPendingBalanceDeposits(deps))
+	require.NoError(t, st.SetPendingDeposits(deps))
 	require.NoError(t, st.SetPendingConsolidations([]*ethpb.PendingConsolidation{
 		{
 			SourceIndex: 2,
@@ -108,7 +111,7 @@ func TestProcessEpoch_CanProcessElectra(t *testing.T) {
 	require.Equal(t, primitives.Gwei(100), res)

 	// Half of the balance deposits should have been processed.
-	remaining, err := st.PendingBalanceDeposits()
+	remaining, err := st.PendingDeposits()
 	require.NoError(t, err)
 	require.Equal(t, 10, len(remaining))

--- a/Show More
+++ b/Show More