Update go to 1.19.4 (#11727 )

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>
Fix DeepSource errors in the Validator's REST API (#11726 )
2026-01-10 05:47:59 -05:00 · 2022-12-06 21:20:25 +00:00 · 2022-12-06 20:31:56 +00:00 · 2022-12-06 16:01:17 +00:00 · 2022-12-06 14:54:45 +00:00 · 2022-12-06 12:27:26 +00:00
1318 changed files with 47005 additions and 36328 deletions
--- a/.bazelrc
+++ b/.bazelrc
@@ -13,7 +13,6 @@ coverage --define=coverage_enabled=1

 # Fix for rules_docker. See: https://github.com/bazelbuild/rules_docker/issues/842
 build --host_force_python=PY2
-test --host_force_python=PY2
 run --host_force_python=PY2

 # Networking is blocked for tests by default, add "requires-network" tag to your test if networking
@@ -22,15 +21,12 @@ build --sandbox_default_allow_network=false

 # Stamp binaries with git information
 build --workspace_status_command=./hack/workspace_status.sh
-build --stamp

 # Prevent PATH changes from rebuilding when switching from IDE to command line.
 build --incompatible_strict_action_env
-test --incompatible_strict_action_env
 run --incompatible_strict_action_env

 build --define blst_disabled=false
-test --define blst_disabled=false
 run --define blst_disabled=false

 build:blst_disabled --define blst_disabled=true
@@ -41,7 +37,6 @@ build:minimal --@io_bazel_rules_go//go/config:tags=minimal

 # Release flags
 build:release --compilation_mode=opt
-build:release --config=llvm

 # LLVM compiler for building C/C++ dependencies.
 build:llvm --define compiler=llvm
@@ -235,3 +230,9 @@ build --modify_execution_info='GoStdlib.*=+no-remote-cache'

 # Set bazel gotag
 build --define gotags=bazel
+
+# Build the binary with Beacon API calls for the validator
+build --flag_alias=use_beacon_api=//validator/client/validator-client-factory:use_beacon_api
+
+build:beacon_api --use_beacon_api
+build:beacon_api --define=gotags=use_beacon_api
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-5.0.0
+5.3.0
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -5,12 +5,4 @@
 *.bzl @prestonvanloon

 # Anyone on prylabs team can approve dependency updates.
-deps.bzl @prysmaticlabs/core-team
-
-# Radek and Nishant are responsible for changes that can affect the native state feature.
-# See https://www.notion.so/prysmaticlabs/Native-Beacon-State-Redesign-6cc9744b4ec1439bb34fa829b36a35c1
-/beacon-chain/state/fieldtrie/ @rkapka @nisdas @rauljordan
-/beacon-chain/state/v1/ @rkapka @nisdas @rauljordan
-/beacon-chain/state/v2/ @rkapka @nisdas @rauljordan
-/beacon-chain/state/v3/ @rkapka @nisdas @rauljordan
-/beacon-chain/state/state-native/ @rkapka @nisdas @rauljordan
+deps.bzl @prysmaticlabs/core-team
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -26,14 +26,14 @@ jobs:
    steps:
      - name: Checkout
        uses: actions/checkout@v2
-      - name: Set up Go 1.18
+      - name: Set up Go 1.19
        uses: actions/setup-go@v3
        with:
-          go-version: 1.18
+          go-version: 1.19
      - name: Run Gosec Security Scanner
        run: | # https://github.com/securego/gosec/issues/469
          export PATH=$PATH:$(go env GOPATH)/bin
-          go install github.com/securego/gosec/v2/cmd/gosec@latest
+          go install github.com/securego/gosec/v2/cmd/gosec@v2.12.0
          gosec -exclude=G307 -exclude-dir=crypto/bls/herumi ./...

  lint:
@@ -43,16 +43,17 @@ jobs:
      - name: Checkout
        uses: actions/checkout@v2

-      - name: Set up Go 1.18
+      - name: Set up Go 1.19
        uses: actions/setup-go@v3
        with:
-          go-version: 1.18
+          go-version: 1.19
          id: go

      - name: Golangci-lint
        uses: golangci/golangci-lint-action@v3
        with:
-          version: v1.47.2
+          version: v1.50.1
+          args: --config=.golangci.yml --out-${NO_FUTURE}format colored-line-number

  build:
    name: Build
@@ -61,7 +62,7 @@ jobs:
      - name: Set up Go 1.x
        uses: actions/setup-go@v2
        with:
-          go-version: 1.18
+          go-version: 1.19
        id: go

      - name: Check out code into the Go module directory
--- a/.gitignore
+++ b/.gitignore
@@ -38,3 +38,6 @@ metaData

 # execution API authentication
 jwt.hex
+
+# manual testing
+tmp
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -6,14 +6,14 @@ run:
    - proto
    - tools/analyzers
  timeout: 10m
-  go: '1.18'
+  go: '1.19'

 linters:
  disable-all: true
  enable:
    - gofmt
    - goimports
-    - deadcode
+    - unused
    - errcheck
    - gosimple
    - gocognit
--- a/README.md
+++ b/README.md
@@ -2,8 +2,8 @@

 [![Build status](https://badge.buildkite.com/b555891daf3614bae4284dcf365b2340cefc0089839526f096.svg?branch=master)](https://buildkite.com/prysmatic-labs/prysm)
 [![Go Report Card](https://goreportcard.com/badge/github.com/prysmaticlabs/prysm)](https://goreportcard.com/report/github.com/prysmaticlabs/prysm)
-[![Consensus_Spec_Version 1.2.0-rc.1](https://img.shields.io/badge/Consensus%20Spec%20Version-v1.2.0.rc.1-blue.svg)](https://github.com/ethereum/consensus-specs/tree/v1.2.0-rc.1)
-[![Execution_API_Version 1.0.0-alpha.9](https://img.shields.io/badge/Execution%20API%20Version-v1.0.0.alpha.9-blue.svg)](https://github.com/ethereum/execution-apis/tree/v1.0.0-alpha.9/src/engine)
+[![Consensus_Spec_Version 1.2.0](https://img.shields.io/badge/Consensus%20Spec%20Version-v1.2.0-blue.svg)](https://github.com/ethereum/consensus-specs/tree/v1.2.0)
+[![Execution_API_Version 1.0.0-beta.1](https://img.shields.io/badge/Execution%20API%20Version-v1.0.0.beta.1-blue.svg)](https://github.com/ethereum/execution-apis/tree/v1.0.0-beta.1/src/engine)
 [![Discord](https://user-images.githubusercontent.com/7288322/34471967-1df7808a-efbb-11e7-9088-ed0b04151291.png)](https://discord.gg/CTYGPUJ)
 [![GitPOAP Badge](https://public-api.gitpoap.io/v1/repo/prysmaticlabs/prysm/badge)](https://www.gitpoap.io/gh/prysmaticlabs/prysm)

--- a/51
+++ b/51
@@ -28,7 +28,7 @@ load("@com_grail_bazel_toolchain//toolchain:rules.bzl", "llvm_toolchain")

 llvm_toolchain(
    name = "llvm_toolchain",
-    llvm_version = "10.0.0",
+    llvm_version = "13.0.1",
 )

 load("@llvm_toolchain//:toolchains.bzl", "llvm_register_toolchains")
@@ -88,10 +88,10 @@ http_archive(
        # Expose internals of go_test for custom build transitions.
        "//third_party:io_bazel_rules_go_test.patch",
    ],
-    sha256 = "16e9fca53ed6bd4ff4ad76facc9b7b651a89db1689a2877d6fd7b82aa824e366",
+    sha256 = "ae013bf35bd23234d1dea46b079f1e05ba74ac0321423830119d3e787ec73483",
    urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.34.0/rules_go-v0.34.0.zip",
-        "https://github.com/bazelbuild/rules_go/releases/download/v0.34.0/rules_go-v0.34.0.zip",
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.36.0/rules_go-v0.36.0.zip",
+        "https://github.com/bazelbuild/rules_go/releases/download/v0.36.0/rules_go-v0.36.0.zip",
    ],
 )

@@ -110,13 +110,6 @@ git_repository(
    # gazelle args: -go_prefix github.com/gogo/protobuf -proto legacy
 )

-http_archive(
-    name = "fuzzit_linux",
-    build_file_content = "exports_files([\"fuzzit\"])",
-    sha256 = "9ca76ac1c22d9360936006efddf992977ebf8e4788ded8e5f9d511285c9ac774",
-    urls = ["https://github.com/fuzzitdev/fuzzit/releases/download/v2.4.76/fuzzit_Linux_x86_64.zip"],
-)
-
 load(
    "@io_bazel_rules_docker//repositories:repositories.bzl",
    container_repositories = "repositories",
@@ -164,35 +157,15 @@ container_pull(
    repository = "pinglamb/alpine-glibc",
 )

-container_pull(
-    name = "fuzzit_base",
-    digest = "sha256:24a39a4360b07b8f0121eb55674a2e757ab09f0baff5569332fefd227ee4338f",
-    registry = "gcr.io",
-    repository = "fuzzit-public/stretch-llvm8",
-)
-
 load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_dependencies")

 go_rules_dependencies()

 go_register_toolchains(
-    go_version = "1.18.5",
+    go_version = "1.19.4",
    nogo = "@//:nogo",
 )

-http_archive(
-    name = "prysm_testnet_site",
-    build_file_content = """
-proto_library(
-  name = "faucet_proto",
-  srcs = ["src/proto/faucet.proto"],
-  visibility = ["//visibility:public"],
-)""",
-    sha256 = "29742136ff9faf47343073c4569a7cf21b8ed138f726929e09e3c38ab83544f7",
-    strip_prefix = "prysm-testnet-site-5c711600f0a77fc553b18cf37b880eaffef4afdb",
-    url = "https://github.com/prestonvanloon/prysm-testnet-site/archive/5c711600f0a77fc553b18cf37b880eaffef4afdb.tar.gz",
-)
-
 http_archive(
    name = "io_kubernetes_build",
    sha256 = "b84fbd1173acee9d02a7d3698ad269fdf4f7aa081e9cecd40e012ad0ad8cfa2a",
@@ -215,7 +188,7 @@ filegroup(
    url = "https://github.com/eth-clients/slashing-protection-interchange-tests/archive/b8413ca42dc92308019d0d4db52c87e9e125c4e9.tar.gz",
 )

-consensus_spec_version = "v1.2.0-rc.2"
+consensus_spec_version = "v1.3.0-alpha.1"

 bls_test_version = "v0.1.1"

@@ -231,7 +204,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "eff52923eebbed6e37a5282db5290abe67c68d6aa54302e3db2b0718c3edf867",
+    sha256 = "b5a65eb5ecef1c4fca82ff29739936fee019e8a529ef392ea5e46aa39f40a0b2",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
 )

@@ -247,7 +220,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "6183d39d40ae659347e8bcfa435cbbe6de8c19ab327b61d47f906bb087bc7a67",
+    sha256 = "b381bb0184e69cb17d05fbbe75f48c6aec7726957d073e3a65c26671d5d27d37",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
 )

@@ -263,7 +236,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "894d16608d7d37a8f6206165e6c2b6ffcc45b13152b5f411e9283b005ca9793f",
+    sha256 = "9466f2a5a2dea039a2deb953f0b5dce5399400028bf3f218ffef03f8ef9c446c",
    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
 )

@@ -278,7 +251,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "006674e5d7eee613f1155e154ab97f6b57589ec92e6e3e5f7affd2b53581e907",
+    sha256 = "3cc3141651a320a1f5767d15826e85aaa96eb4459d9e1a1d3f5a0cdbc79b8f56",
    strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
    url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
@@ -342,9 +315,9 @@ filegroup(
    visibility = ["//visibility:public"],
 )
 """,
-    sha256 = "e0c0b5dc609b3a221e74c720f483c595441f2ad5e38bb8aa3522636039945a6f",
+    sha256 = "b2226874526805d64c29e5053fa28e511b57c0860585d6d59777ee81ff4859ca",
    urls = [
-        "https://github.com/prysmaticlabs/prysm-web-ui/releases/download/v2.0.1/prysm-web-ui.tar.gz",
+        "https://github.com/prysmaticlabs/prysm-web-ui/releases/download/v2.0.2/prysm-web-ui.tar.gz",
    ],
 )

--- a/api/client/beacon/checkpoint.go
+++ b/api/client/beacon/checkpoint.go
@@ -21,14 +21,13 @@ import (
 // OriginData represents the BeaconState and SignedBeaconBlock necessary to start an empty Beacon Node
 // using Checkpoint Sync.
 type OriginData struct {
-	wsd *WeakSubjectivityData
-	sb  []byte
-	bb  []byte
-	st  state.BeaconState
-	b   interfaces.SignedBeaconBlock
-	vu  *detect.VersionedUnmarshaler
-	br  [32]byte
-	sr  [32]byte
+	sb []byte
+	bb []byte
+	st state.BeaconState
+	b  interfaces.SignedBeaconBlock
+	vu *detect.VersionedUnmarshaler
+	br [32]byte
+	sr [32]byte
 }

 // SaveBlock saves the downloaded block to a unique file in the given path.
@@ -75,6 +74,9 @@ func DownloadFinalizedData(ctx context.Context, client *Client) (*OriginData, er
 	if err != nil {
 		return nil, errors.Wrap(err, "error unmarshaling finalized state to correct version")
 	}
+	if s.Slot() != s.LatestBlockHeader().Slot {
+		return nil, fmt.Errorf("finalized state slot does not match latest block header slot %d != %d", s.Slot(), s.LatestBlockHeader().Slot)
+	}

 	sr, err := s.HashTreeRoot(ctx)
 	if err != nil {
--- a/api/client/beacon/checkpoint_test.go
+++ b/api/client/beacon/checkpoint_test.go
@@ -418,6 +418,7 @@ func TestDownloadFinalizedData(t *testing.T) {
 	require.NoError(t, err)
 	fork, err := forkForEpoch(cfg, epoch)
 	require.NoError(t, st.SetFork(fork))
+	require.NoError(t, st.SetSlot(slot))

 	// set up checkpoint block
 	b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
--- a/api/client/beacon/client.go
+++ b/api/client/beacon/client.go
@@ -95,8 +95,6 @@ func WithTimeout(timeout time.Duration) ClientOpt {
 // Client provides a collection of helper methods for calling the Eth Beacon Node API endpoints.
 type Client struct {
 	hc      *http.Client
-	host    string
-	scheme  string
 	baseURL *url.URL
 }

--- a/api/client/beacon/doc.go
+++ b/api/client/beacon/doc.go
@@ -1,6 +1,5 @@
 /*
 Package beacon provides a client for interacting with the standard Eth Beacon Node API.
 Interactive swagger documentation for the API is available here: https://ethereum.github.io/beacon-APIs/
-
 */
 package beacon
--- a/api/client/builder/BUILD.bazel
+++ b/api/client/builder/BUILD.bazel
@@ -13,6 +13,8 @@ go_library(
        "//consensus-types/primitives:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//monitoring/tracing:go_default_library",
+        "//network:go_default_library",
+        "//network/authorization:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
--- a/api/client/builder/client.go
+++ b/api/client/builder/client.go
@@ -15,6 +15,8 @@ import (
 	"github.com/pkg/errors"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/monitoring/tracing"
+	"github.com/prysmaticlabs/prysm/v3/network"
+	"github.com/prysmaticlabs/prysm/v3/network/authorization"
 	v1 "github.com/prysmaticlabs/prysm/v3/proto/engine/v1"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	log "github.com/sirupsen/logrus"
@@ -30,17 +32,11 @@ const (

 var errMalformedHostname = errors.New("hostname must include port, separated by one colon, like example.com:3500")
 var errMalformedRequest = errors.New("required request data are missing")
+var submitBlindedBlockTimeout = 3 * time.Second

 // ClientOpt is a functional option for the Client type (http.Client wrapper)
 type ClientOpt func(*Client)

-// WithTimeout sets the .Timeout attribute of the wrapped http.Client.
-func WithTimeout(timeout time.Duration) ClientOpt {
-	return func(c *Client) {
-		c.hc.Timeout = timeout
-	}
-}
-
 type observer interface {
 	observe(r *http.Request) error
 }
@@ -83,6 +79,15 @@ func (*requestLogger) observe(r *http.Request) (e error) {

 var _ observer = &requestLogger{}

+// BuilderClient provides a collection of helper methods for calling Builder API endpoints.
+type BuilderClient interface {
+	NodeURL() string
+	GetHeader(ctx context.Context, slot types.Slot, parentHash [32]byte, pubkey [48]byte) (*ethpb.SignedBuilderBid, error)
+	RegisterValidator(ctx context.Context, svr []*ethpb.SignedValidatorRegistrationV1) error
+	SubmitBlindedBlock(ctx context.Context, sb *ethpb.SignedBlindedBeaconBlockBellatrix) (*v1.ExecutionPayload, error)
+	Status(ctx context.Context) error
+}
+
 // Client provides a collection of helper methods for calling Builder API endpoints.
 type Client struct {
 	hc      *http.Client
@@ -94,7 +99,8 @@ type Client struct {
 // `host` is the base host + port used to construct request urls. This value can be
 // a URL string, or NewClient will assume an http endpoint if just `host:port` is used.
 func NewClient(host string, opts ...ClientOpt) (*Client, error) {
-	u, err := urlForHost(host)
+	endpoint := covertEndPoint(host)
+	u, err := urlForHost(endpoint.Url)
 	if err != nil {
 		return nil, err
 	}
@@ -248,7 +254,11 @@ func (c *Client) SubmitBlindedBlock(ctx context.Context, sb *ethpb.SignedBlinded
 	if err != nil {
 		return nil, errors.Wrap(err, "error encoding the SignedBlindedBeaconBlockBellatrix value body in SubmitBlindedBlock")
 	}
+
+	ctx, cancel := context.WithTimeout(ctx, submitBlindedBlockTimeout)
+	defer cancel()
 	rb, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body))
+
 	if err != nil {
 		return nil, errors.Wrap(err, "error posting the SignedBlindedBeaconBlockBellatrix to the builder api")
 	}
@@ -274,9 +284,6 @@ func non200Err(response *http.Response) error {
 	if err != nil {
 		body = "(Unable to read response body.)"
 	} else {
-		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
-			return errors.Wrap(jsonErr, "unable to read response body")
-		}
 		body = "response body:\n" + string(bodyBytes)
 	}
 	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
@@ -285,13 +292,34 @@ func non200Err(response *http.Response) error {
 		log.WithError(ErrNoContent).Debug(msg)
 		return ErrNoContent
 	case 400:
+		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
+			return errors.Wrap(jsonErr, "unable to read response body")
+		}
 		log.WithError(ErrBadRequest).Debug(msg)
 		return errors.Wrap(ErrBadRequest, errMessage.Message)
 	case 404:
+		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
+			return errors.Wrap(jsonErr, "unable to read response body")
+		}
 		log.WithError(ErrNotFound).Debug(msg)
 		return errors.Wrap(ErrNotFound, errMessage.Message)
-	default:
+	case 500:
+		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
+			return errors.Wrap(jsonErr, "unable to read response body")
+		}
 		log.WithError(ErrNotOK).Debug(msg)
 		return errors.Wrap(ErrNotOK, errMessage.Message)
+	default:
+		log.WithError(ErrNotOK).Debug(msg)
+		return errors.Wrap(ErrNotOK, fmt.Sprintf("unsupported error code: %d", response.StatusCode))
 	}
 }
+
+func covertEndPoint(ep string) network.Endpoint {
+	return network.Endpoint{
+		Url: ep,
+		Auth: network.AuthorizationData{ // Auth is not used for builder.
+			Method: authorization.None,
+			Value:  "",
+		}}
+}
--- a/api/client/builder/client_test.go
+++ b/api/client/builder/client_test.go
@@ -81,7 +81,7 @@ func TestClient_Status(t *testing.T) {

 func TestClient_RegisterValidator(t *testing.T) {
 	ctx := context.Background()
-	expectedBody := `[{"message":{"fee_recipient":"0x0000000000000000000000000000000000000000","gas_limit":"23","timestamp":"42","pubkey":"0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"}}]`
+	expectedBody := `[{"message":{"fee_recipient":"0x0000000000000000000000000000000000000000","gas_limit":"23","timestamp":"42","pubkey":"0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}]`
 	expectedPath := "/eth/v1/builder/validators"
 	hc := &http.Client{
 		Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
@@ -111,6 +111,7 @@ func TestClient_RegisterValidator(t *testing.T) {
 			Timestamp:    42,
 			Pubkey:       ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
 		},
+		Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
 	}
 	require.NoError(t, c.RegisterValidator(ctx, []*eth.SignedValidatorRegistrationV1{reg}))
 }
@@ -144,6 +145,23 @@ func TestClient_GetHeader(t *testing.T) {
 	_, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
 	require.ErrorIs(t, err, ErrNotOK)

+	hc = &http.Client{
+		Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+			require.Equal(t, expectedPath, r.URL.Path)
+			return &http.Response{
+				StatusCode: http.StatusNoContent,
+				Body:       io.NopCloser(bytes.NewBuffer([]byte("No header is available."))),
+				Request:    r.Clone(ctx),
+			}, nil
+		}),
+	}
+	c = &Client{
+		hc:      hc,
+		baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
+	}
+	_, err = c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
+	require.ErrorIs(t, err, ErrNoContent)
+
 	hc = &http.Client{
 		Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
 			require.Equal(t, expectedPath, r.URL.Path)
@@ -165,7 +183,8 @@ func TestClient_GetHeader(t *testing.T) {
 	expectedTxRoot := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
 	require.Equal(t, true, bytes.Equal(expectedTxRoot, h.Message.Header.TransactionsRoot))
 	require.Equal(t, uint64(1), h.Message.Header.GasUsed)
-	value := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+	value, err := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
 	require.Equal(t, fmt.Sprintf("%#x", value.SSZBytes()), fmt.Sprintf("%#x", h.Message.Value))
 }

@@ -189,7 +208,8 @@ func TestSubmitBlindedBlock(t *testing.T) {
 	ep, err := c.SubmitBlindedBlock(ctx, sbbb)
 	require.NoError(t, err)
 	require.Equal(t, true, bytes.Equal(ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"), ep.ParentHash))
-	bfpg := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
 	require.Equal(t, fmt.Sprintf("%#x", bfpg.SSZBytes()), fmt.Sprintf("%#x", ep.BaseFeePerGas))
 	require.Equal(t, uint64(1), ep.GasLimit)
 }
--- a/api/client/builder/testing/BUILD.bazel
+++ b/api/client/builder/testing/BUILD.bazel
@@ -0,0 +1,14 @@
+load("@prysm//tools/go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["mock.go"],
+    importpath = "github.com/prysmaticlabs/prysm/v3/api/client/builder/testing",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//consensus-types/primitives:go_default_library",
+        "//encoding/bytesutil:go_default_library",
+        "//proto/engine/v1:go_default_library",
+        "//proto/prysm/v1alpha1:go_default_library",
+    ],
+)
--- a/api/client/builder/testing/mock.go
+++ b/api/client/builder/testing/mock.go
@@ -0,0 +1,49 @@
+package testing
+
+import (
+	"context"
+
+	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
+	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
+	v1 "github.com/prysmaticlabs/prysm/v3/proto/engine/v1"
+	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
+)
+
+// MockClient is a mock implementation of BuilderClient.
+type MockClient struct {
+	RegisteredVals map[[48]byte]bool
+}
+
+// NewClient creates a new, correctly initialized mock.
+func NewClient() MockClient {
+	return MockClient{RegisteredVals: map[[48]byte]bool{}}
+}
+
+// NodeURL --
+func (MockClient) NodeURL() string {
+	return ""
+}
+
+// GetHeader --
+func (MockClient) GetHeader(_ context.Context, _ types.Slot, _ [32]byte, _ [48]byte) (*ethpb.SignedBuilderBid, error) {
+	return nil, nil
+}
+
+// RegisterValidator --
+func (m MockClient) RegisterValidator(_ context.Context, svr []*ethpb.SignedValidatorRegistrationV1) error {
+	for _, r := range svr {
+		b := bytesutil.ToBytes48(r.Message.Pubkey)
+		m.RegisteredVals[b] = true
+	}
+	return nil
+}
+
+// SubmitBlindedBlock --
+func (MockClient) SubmitBlindedBlock(_ context.Context, _ *ethpb.SignedBlindedBeaconBlockBellatrix) (*v1.ExecutionPayload, error) {
+	return nil, nil
+}
+
+// Status --
+func (MockClient) Status(_ context.Context) error {
+	return nil
+}
--- a/api/client/builder/types.go
+++ b/api/client/builder/types.go
@@ -23,8 +23,8 @@ type ValidatorRegistration struct {

 func (r *SignedValidatorRegistration) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Message   *ValidatorRegistration `json:"message,omitempty"`
-		Signature hexutil.Bytes          `json:"signature,omitempty"`
+		Message   *ValidatorRegistration `json:"message"`
+		Signature hexutil.Bytes          `json:"signature"`
 	}{
 		Message:   &ValidatorRegistration{r.Message},
 		Signature: r.SignedValidatorRegistrationV1.Signature,
@@ -36,8 +36,8 @@ func (r *SignedValidatorRegistration) UnmarshalJSON(b []byte) error {
 		r.SignedValidatorRegistrationV1 = &eth.SignedValidatorRegistrationV1{}
 	}
 	o := struct {
-		Message   *ValidatorRegistration `json:"message,omitempty"`
-		Signature hexutil.Bytes          `json:"signature,omitempty"`
+		Message   *ValidatorRegistration `json:"message"`
+		Signature hexutil.Bytes          `json:"signature"`
 	}{}
 	if err := json.Unmarshal(b, &o); err != nil {
 		return err
@@ -49,10 +49,10 @@ func (r *SignedValidatorRegistration) UnmarshalJSON(b []byte) error {

 func (r *ValidatorRegistration) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		FeeRecipient hexutil.Bytes `json:"fee_recipient,omitempty"`
-		GasLimit     string        `json:"gas_limit,omitempty"`
-		Timestamp    string        `json:"timestamp,omitempty"`
-		Pubkey       hexutil.Bytes `json:"pubkey,omitempty"`
+		FeeRecipient hexutil.Bytes `json:"fee_recipient"`
+		GasLimit     string        `json:"gas_limit"`
+		Timestamp    string        `json:"timestamp"`
+		Pubkey       hexutil.Bytes `json:"pubkey"`
 	}{
 		FeeRecipient: r.FeeRecipient,
 		GasLimit:     fmt.Sprintf("%d", r.GasLimit),
@@ -66,10 +66,10 @@ func (r *ValidatorRegistration) UnmarshalJSON(b []byte) error {
 		r.ValidatorRegistrationV1 = &eth.ValidatorRegistrationV1{}
 	}
 	o := struct {
-		FeeRecipient hexutil.Bytes `json:"fee_recipient,omitempty"`
-		GasLimit     string        `json:"gas_limit,omitempty"`
-		Timestamp    string        `json:"timestamp,omitempty"`
-		Pubkey       hexutil.Bytes `json:"pubkey,omitempty"`
+		FeeRecipient hexutil.Bytes `json:"fee_recipient"`
+		GasLimit     string        `json:"gas_limit"`
+		Timestamp    string        `json:"timestamp"`
+		Pubkey       hexutil.Bytes `json:"pubkey"`
 	}{}
 	if err := json.Unmarshal(b, &o); err != nil {
 		return err
@@ -88,29 +88,44 @@ func (r *ValidatorRegistration) UnmarshalJSON(b []byte) error {
 	return nil
 }

+var errInvalidUint256 = errors.New("invalid Uint256")
+var errDecodeUint256 = errors.New("unable to decode into Uint256")
+
 type Uint256 struct {
 	*big.Int
 }

-func stringToUint256(s string) Uint256 {
+func isValidUint256(bi *big.Int) bool {
+	return bi.Cmp(big.NewInt(0)) >= 0 && bi.BitLen() <= 256
+}
+
+func stringToUint256(s string) (Uint256, error) {
 	bi := new(big.Int)
-	bi.SetString(s, 10)
-	return Uint256{Int: bi}
+	_, ok := bi.SetString(s, 10)
+	if !ok || !isValidUint256(bi) {
+		return Uint256{}, errors.Wrapf(errDecodeUint256, "value=%s", s)
+	}
+	return Uint256{Int: bi}, nil
 }

 // sszBytesToUint256 creates a Uint256 from a ssz-style (little-endian byte slice) representation.
-func sszBytesToUint256(b []byte) Uint256 {
+func sszBytesToUint256(b []byte) (Uint256, error) {
 	bi := new(big.Int)
-	return Uint256{Int: bi.SetBytes(bytesutil.ReverseByteOrder(b))}
+	bi.SetBytes(bytesutil.ReverseByteOrder(b))
+	if !isValidUint256(bi) {
+		return Uint256{}, errors.Wrapf(errDecodeUint256, "value=%s", b)
+	}
+	return Uint256{Int: bi}, nil
 }

 // SSZBytes creates an ssz-style (little-endian byte slice) representation of the Uint256
 func (s Uint256) SSZBytes() []byte {
+	if !isValidUint256(s.Int) {
+		return []byte{}
+	}
 	return bytesutil.PadTo(bytesutil.ReverseByteOrder(s.Int.Bytes()), 32)
 }

-var errUnmarshalUint256Failed = errors.New("unable to UnmarshalText into a Uint256 value")
-
 func (s *Uint256) UnmarshalJSON(t []byte) error {
 	start := 0
 	end := len(t)
@@ -129,7 +144,10 @@ func (s *Uint256) UnmarshalText(t []byte) error {
 	}
 	z, ok := s.SetString(string(t), 10)
 	if !ok {
-		return errors.Wrapf(errUnmarshalUint256Failed, "value=%s", string(t))
+		return errors.Wrapf(errDecodeUint256, "value=%s", t)
+	}
+	if !isValidUint256(z) {
+		return errors.Wrapf(errDecodeUint256, "value=%s", t)
 	}
 	s.Int = z
 	return nil
@@ -146,6 +164,9 @@ func (s Uint256) MarshalJSON() ([]byte, error) {
 }

 func (s Uint256) MarshalText() ([]byte, error) {
+	if !isValidUint256(s.Int) {
+		return nil, errors.Wrapf(errInvalidUint256, "value=%s", s.Int)
+	}
 	return []byte(s.String()), nil
 }

@@ -162,11 +183,11 @@ func (s Uint64String) MarshalText() ([]byte, error) {
 }

 type ExecHeaderResponse struct {
-	Version string `json:"version,omitempty"`
+	Version string `json:"version"`
 	Data    struct {
-		Signature hexutil.Bytes `json:"signature,omitempty"`
-		Message   *BuilderBid   `json:"message,omitempty"`
-	} `json:"data,omitempty"`
+		Signature hexutil.Bytes `json:"signature"`
+		Message   *BuilderBid   `json:"message"`
+	} `json:"data"`
 }

 func (ehr *ExecHeaderResponse) ToProto() (*eth.SignedBuilderBid, error) {
@@ -212,31 +233,35 @@ func (h *ExecutionPayloadHeader) ToProto() (*v1.ExecutionPayloadHeader, error) {
 }

 type BuilderBid struct {
-	Header *ExecutionPayloadHeader `json:"header,omitempty"`
-	Value  Uint256                 `json:"value,omitempty"`
-	Pubkey hexutil.Bytes           `json:"pubkey,omitempty"`
+	Header *ExecutionPayloadHeader `json:"header"`
+	Value  Uint256                 `json:"value"`
+	Pubkey hexutil.Bytes           `json:"pubkey"`
 }

 type ExecutionPayloadHeader struct {
-	ParentHash       hexutil.Bytes `json:"parent_hash,omitempty"`
-	FeeRecipient     hexutil.Bytes `json:"fee_recipient,omitempty"`
-	StateRoot        hexutil.Bytes `json:"state_root,omitempty"`
-	ReceiptsRoot     hexutil.Bytes `json:"receipts_root,omitempty"`
-	LogsBloom        hexutil.Bytes `json:"logs_bloom,omitempty"`
-	PrevRandao       hexutil.Bytes `json:"prev_randao,omitempty"`
-	BlockNumber      Uint64String  `json:"block_number,omitempty"`
-	GasLimit         Uint64String  `json:"gas_limit,omitempty"`
-	GasUsed          Uint64String  `json:"gas_used,omitempty"`
-	Timestamp        Uint64String  `json:"timestamp,omitempty"`
-	ExtraData        hexutil.Bytes `json:"extra_data,omitempty"`
-	BaseFeePerGas    Uint256       `json:"base_fee_per_gas,omitempty"`
-	BlockHash        hexutil.Bytes `json:"block_hash,omitempty"`
-	TransactionsRoot hexutil.Bytes `json:"transactions_root,omitempty"`
+	ParentHash       hexutil.Bytes `json:"parent_hash"`
+	FeeRecipient     hexutil.Bytes `json:"fee_recipient"`
+	StateRoot        hexutil.Bytes `json:"state_root"`
+	ReceiptsRoot     hexutil.Bytes `json:"receipts_root"`
+	LogsBloom        hexutil.Bytes `json:"logs_bloom"`
+	PrevRandao       hexutil.Bytes `json:"prev_randao"`
+	BlockNumber      Uint64String  `json:"block_number"`
+	GasLimit         Uint64String  `json:"gas_limit"`
+	GasUsed          Uint64String  `json:"gas_used"`
+	Timestamp        Uint64String  `json:"timestamp"`
+	ExtraData        hexutil.Bytes `json:"extra_data"`
+	BaseFeePerGas    Uint256       `json:"base_fee_per_gas"`
+	BlockHash        hexutil.Bytes `json:"block_hash"`
+	TransactionsRoot hexutil.Bytes `json:"transactions_root"`
 	*v1.ExecutionPayloadHeader
 }

 func (h *ExecutionPayloadHeader) MarshalJSON() ([]byte, error) {
 	type MarshalCaller ExecutionPayloadHeader
+	baseFeePerGas, err := sszBytesToUint256(h.ExecutionPayloadHeader.BaseFeePerGas)
+	if err != nil {
+		return []byte{}, errors.Wrapf(err, "invalid BaseFeePerGas")
+	}
 	return json.Marshal(&MarshalCaller{
 		ParentHash:       h.ExecutionPayloadHeader.ParentHash,
 		FeeRecipient:     h.ExecutionPayloadHeader.FeeRecipient,
@@ -249,7 +274,7 @@ func (h *ExecutionPayloadHeader) MarshalJSON() ([]byte, error) {
 		GasUsed:          Uint64String(h.ExecutionPayloadHeader.GasUsed),
 		Timestamp:        Uint64String(h.ExecutionPayloadHeader.Timestamp),
 		ExtraData:        h.ExecutionPayloadHeader.ExtraData,
-		BaseFeePerGas:    sszBytesToUint256(h.ExecutionPayloadHeader.BaseFeePerGas),
+		BaseFeePerGas:    baseFeePerGas,
 		BlockHash:        h.ExecutionPayloadHeader.BlockHash,
 		TransactionsRoot: h.ExecutionPayloadHeader.TransactionsRoot,
 	})
@@ -269,25 +294,25 @@ func (h *ExecutionPayloadHeader) UnmarshalJSON(b []byte) error {
 }

 type ExecPayloadResponse struct {
-	Version string           `json:"version,omitempty"`
-	Data    ExecutionPayload `json:"data,omitempty"`
+	Version string           `json:"version"`
+	Data    ExecutionPayload `json:"data"`
 }

 type ExecutionPayload struct {
-	ParentHash    hexutil.Bytes   `json:"parent_hash,omitempty"`
-	FeeRecipient  hexutil.Bytes   `json:"fee_recipient,omitempty"`
-	StateRoot     hexutil.Bytes   `json:"state_root,omitempty"`
-	ReceiptsRoot  hexutil.Bytes   `json:"receipts_root,omitempty"`
-	LogsBloom     hexutil.Bytes   `json:"logs_bloom,omitempty"`
-	PrevRandao    hexutil.Bytes   `json:"prev_randao,omitempty"`
-	BlockNumber   Uint64String    `json:"block_number,omitempty"`
-	GasLimit      Uint64String    `json:"gas_limit,omitempty"`
-	GasUsed       Uint64String    `json:"gas_used,omitempty"`
-	Timestamp     Uint64String    `json:"timestamp,omitempty"`
-	ExtraData     hexutil.Bytes   `json:"extra_data,omitempty"`
-	BaseFeePerGas Uint256         `json:"base_fee_per_gas,omitempty"`
-	BlockHash     hexutil.Bytes   `json:"block_hash,omitempty"`
-	Transactions  []hexutil.Bytes `json:"transactions,omitempty"`
+	ParentHash    hexutil.Bytes   `json:"parent_hash"`
+	FeeRecipient  hexutil.Bytes   `json:"fee_recipient"`
+	StateRoot     hexutil.Bytes   `json:"state_root"`
+	ReceiptsRoot  hexutil.Bytes   `json:"receipts_root"`
+	LogsBloom     hexutil.Bytes   `json:"logs_bloom"`
+	PrevRandao    hexutil.Bytes   `json:"prev_randao"`
+	BlockNumber   Uint64String    `json:"block_number"`
+	GasLimit      Uint64String    `json:"gas_limit"`
+	GasUsed       Uint64String    `json:"gas_used"`
+	Timestamp     Uint64String    `json:"timestamp"`
+	ExtraData     hexutil.Bytes   `json:"extra_data"`
+	BaseFeePerGas Uint256         `json:"base_fee_per_gas"`
+	BlockHash     hexutil.Bytes   `json:"block_hash"`
+	Transactions  []hexutil.Bytes `json:"transactions"`
 }

 func (r *ExecPayloadResponse) ToProto() (*v1.ExecutionPayload, error) {
@@ -331,8 +356,8 @@ type BlindedBeaconBlockBodyBellatrix struct {

 func (r *SignedBlindedBeaconBlockBellatrix) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Message   *BlindedBeaconBlockBellatrix `json:"message,omitempty"`
-		Signature hexutil.Bytes                `json:"signature,omitempty"`
+		Message   *BlindedBeaconBlockBellatrix `json:"message"`
+		Signature hexutil.Bytes                `json:"signature"`
 	}{
 		Message:   &BlindedBeaconBlockBellatrix{r.SignedBlindedBeaconBlockBellatrix.Block},
 		Signature: r.SignedBlindedBeaconBlockBellatrix.Signature,
@@ -342,10 +367,10 @@ func (r *SignedBlindedBeaconBlockBellatrix) MarshalJSON() ([]byte, error) {
 func (b *BlindedBeaconBlockBellatrix) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
 		Slot          string                           `json:"slot"`
-		ProposerIndex string                           `json:"proposer_index,omitempty"`
-		ParentRoot    hexutil.Bytes                    `json:"parent_root,omitempty"`
-		StateRoot     hexutil.Bytes                    `json:"state_root,omitempty"`
-		Body          *BlindedBeaconBlockBodyBellatrix `json:"body,omitempty"`
+		ProposerIndex string                           `json:"proposer_index"`
+		ParentRoot    hexutil.Bytes                    `json:"parent_root"`
+		StateRoot     hexutil.Bytes                    `json:"state_root"`
+		Body          *BlindedBeaconBlockBodyBellatrix `json:"body"`
 	}{
 		Slot:          fmt.Sprintf("%d", b.Slot),
 		ProposerIndex: fmt.Sprintf("%d", b.ProposerIndex),
@@ -361,8 +386,8 @@ type ProposerSlashing struct {

 func (s *ProposerSlashing) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		SignedHeader1 *SignedBeaconBlockHeader `json:"signed_header_1,omitempty"`
-		SignedHeader2 *SignedBeaconBlockHeader `json:"signed_header_2,omitempty"`
+		SignedHeader1 *SignedBeaconBlockHeader `json:"signed_header_1"`
+		SignedHeader2 *SignedBeaconBlockHeader `json:"signed_header_2"`
 	}{
 		SignedHeader1: &SignedBeaconBlockHeader{s.ProposerSlashing.Header_1},
 		SignedHeader2: &SignedBeaconBlockHeader{s.ProposerSlashing.Header_2},
@@ -375,8 +400,8 @@ type SignedBeaconBlockHeader struct {

 func (h *SignedBeaconBlockHeader) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Header    *BeaconBlockHeader `json:"message,omitempty"`
-		Signature hexutil.Bytes      `json:"signature,omitempty"`
+		Header    *BeaconBlockHeader `json:"message"`
+		Signature hexutil.Bytes      `json:"signature"`
 	}{
 		Header:    &BeaconBlockHeader{h.SignedBeaconBlockHeader.Header},
 		Signature: h.SignedBeaconBlockHeader.Signature,
@@ -389,11 +414,11 @@ type BeaconBlockHeader struct {

 func (h *BeaconBlockHeader) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Slot          string        `json:"slot,omitempty"`
-		ProposerIndex string        `json:"proposer_index,omitempty"`
-		ParentRoot    hexutil.Bytes `json:"parent_root,omitempty"`
-		StateRoot     hexutil.Bytes `json:"state_root,omitempty"`
-		BodyRoot      hexutil.Bytes `json:"body_root,omitempty"`
+		Slot          string        `json:"slot"`
+		ProposerIndex string        `json:"proposer_index"`
+		ParentRoot    hexutil.Bytes `json:"parent_root"`
+		StateRoot     hexutil.Bytes `json:"state_root"`
+		BodyRoot      hexutil.Bytes `json:"body_root"`
 	}{
 		Slot:          fmt.Sprintf("%d", h.BeaconBlockHeader.Slot),
 		ProposerIndex: fmt.Sprintf("%d", h.BeaconBlockHeader.ProposerIndex),
@@ -413,9 +438,9 @@ func (a *IndexedAttestation) MarshalJSON() ([]byte, error) {
 		indices[i] = fmt.Sprintf("%d", a.AttestingIndices[i])
 	}
 	return json.Marshal(struct {
-		AttestingIndices []string         `json:"attesting_indices,omitempty"`
-		Data             *AttestationData `json:"data,omitempty"`
-		Signature        hexutil.Bytes    `json:"signature,omitempty"`
+		AttestingIndices []string         `json:"attesting_indices"`
+		Data             *AttestationData `json:"data"`
+		Signature        hexutil.Bytes    `json:"signature"`
 	}{
 		AttestingIndices: indices,
 		Data:             &AttestationData{a.IndexedAttestation.Data},
@@ -429,8 +454,8 @@ type AttesterSlashing struct {

 func (s *AttesterSlashing) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Attestation1 *IndexedAttestation `json:"attestation_1,omitempty"`
-		Attestation2 *IndexedAttestation `json:"attestation_2,omitempty"`
+		Attestation1 *IndexedAttestation `json:"attestation_1"`
+		Attestation2 *IndexedAttestation `json:"attestation_2"`
 	}{
 		Attestation1: &IndexedAttestation{s.Attestation_1},
 		Attestation2: &IndexedAttestation{s.Attestation_2},
@@ -443,8 +468,8 @@ type Checkpoint struct {

 func (c *Checkpoint) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Epoch string        `json:"epoch,omitempty"`
-		Root  hexutil.Bytes `json:"root,omitempty"`
+		Epoch string        `json:"epoch"`
+		Root  hexutil.Bytes `json:"root"`
 	}{
 		Epoch: fmt.Sprintf("%d", c.Checkpoint.Epoch),
 		Root:  c.Checkpoint.Root,
@@ -457,11 +482,11 @@ type AttestationData struct {

 func (a *AttestationData) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Slot            string        `json:"slot,omitempty"`
-		Index           string        `json:"index,omitempty"`
-		BeaconBlockRoot hexutil.Bytes `json:"beacon_block_root,omitempty"`
-		Source          *Checkpoint   `json:"source,omitempty"`
-		Target          *Checkpoint   `json:"target,omitempty"`
+		Slot            string        `json:"slot"`
+		Index           string        `json:"index"`
+		BeaconBlockRoot hexutil.Bytes `json:"beacon_block_root"`
+		Source          *Checkpoint   `json:"source"`
+		Target          *Checkpoint   `json:"target"`
 	}{
 		Slot:            fmt.Sprintf("%d", a.AttestationData.Slot),
 		Index:           fmt.Sprintf("%d", a.AttestationData.CommitteeIndex),
@@ -477,9 +502,9 @@ type Attestation struct {

 func (a *Attestation) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		AggregationBits hexutil.Bytes    `json:"aggregation_bits,omitempty"`
-		Data            *AttestationData `json:"data,omitempty"`
-		Signature       hexutil.Bytes    `json:"signature,omitempty" ssz-size:"96"`
+		AggregationBits hexutil.Bytes    `json:"aggregation_bits"`
+		Data            *AttestationData `json:"data"`
+		Signature       hexutil.Bytes    `json:"signature" ssz-size:"96"`
 	}{
 		AggregationBits: hexutil.Bytes(a.Attestation.AggregationBits),
 		Data:            &AttestationData{a.Attestation.Data},
@@ -493,10 +518,10 @@ type DepositData struct {

 func (d *DepositData) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		PublicKey             hexutil.Bytes `json:"pubkey,omitempty"`
-		WithdrawalCredentials hexutil.Bytes `json:"withdrawal_credentials,omitempty"`
-		Amount                string        `json:"amount,omitempty"`
-		Signature             hexutil.Bytes `json:"signature,omitempty"`
+		PublicKey             hexutil.Bytes `json:"pubkey"`
+		WithdrawalCredentials hexutil.Bytes `json:"withdrawal_credentials"`
+		Amount                string        `json:"amount"`
+		Signature             hexutil.Bytes `json:"signature"`
 	}{
 		PublicKey:             d.PublicKey,
 		WithdrawalCredentials: d.WithdrawalCredentials,
@@ -529,8 +554,8 @@ type SignedVoluntaryExit struct {

 func (sve *SignedVoluntaryExit) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Message   *VoluntaryExit `json:"message,omitempty"`
-		Signature hexutil.Bytes  `json:"signature,omitempty"`
+		Message   *VoluntaryExit `json:"message"`
+		Signature hexutil.Bytes  `json:"signature"`
 	}{
 		Signature: sve.SignedVoluntaryExit.Signature,
 		Message:   &VoluntaryExit{sve.SignedVoluntaryExit.Exit},
@@ -543,8 +568,8 @@ type VoluntaryExit struct {

 func (ve *VoluntaryExit) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		Epoch          string `json:"epoch,omitempty"`
-		ValidatorIndex string `json:"validator_index,omitempty"`
+		Epoch          string `json:"epoch"`
+		ValidatorIndex string `json:"validator_index"`
 	}{
 		Epoch:          fmt.Sprintf("%d", ve.Epoch),
 		ValidatorIndex: fmt.Sprintf("%d", ve.ValidatorIndex),
@@ -557,8 +582,8 @@ type SyncAggregate struct {

 func (s *SyncAggregate) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		SyncCommitteeBits      hexutil.Bytes `json:"sync_committee_bits,omitempty"`
-		SyncCommitteeSignature hexutil.Bytes `json:"sync_committee_signature,omitempty"`
+		SyncCommitteeBits      hexutil.Bytes `json:"sync_committee_bits"`
+		SyncCommitteeSignature hexutil.Bytes `json:"sync_committee_signature"`
 	}{
 		SyncCommitteeBits:      hexutil.Bytes(s.SyncAggregate.SyncCommitteeBits),
 		SyncCommitteeSignature: s.SyncAggregate.SyncCommitteeSignature,
@@ -571,9 +596,9 @@ type Eth1Data struct {

 func (e *Eth1Data) MarshalJSON() ([]byte, error) {
 	return json.Marshal(struct {
-		DepositRoot  hexutil.Bytes `json:"deposit_root,omitempty"`
-		DepositCount string        `json:"deposit_count,omitempty"`
-		BlockHash    hexutil.Bytes `json:"block_hash,omitempty"`
+		DepositRoot  hexutil.Bytes `json:"deposit_root"`
+		DepositCount string        `json:"deposit_count"`
+		BlockHash    hexutil.Bytes `json:"block_hash"`
 	}{
 		DepositRoot:  e.DepositRoot,
 		DepositCount: fmt.Sprintf("%d", e.DepositCount),
@@ -603,16 +628,16 @@ func (b *BlindedBeaconBlockBodyBellatrix) MarshalJSON() ([]byte, error) {
 		pros[i] = &ProposerSlashing{ProposerSlashing: b.BlindedBeaconBlockBodyBellatrix.ProposerSlashings[i]}
 	}
 	return json.Marshal(struct {
-		RandaoReveal           hexutil.Bytes           `json:"randao_reveal,omitempty"`
-		Eth1Data               *Eth1Data               `json:"eth1_data,omitempty"`
-		Graffiti               hexutil.Bytes           `json:"graffiti,omitempty"`
-		ProposerSlashings      []*ProposerSlashing     `json:"proposer_slashings,omitempty"`
-		AttesterSlashings      []*AttesterSlashing     `json:"attester_slashings,omitempty"`
-		Attestations           []*Attestation          `json:"attestations,omitempty"`
-		Deposits               []*Deposit              `json:"deposits,omitempty"`
-		VoluntaryExits         []*SignedVoluntaryExit  `json:"voluntary_exits,omitempty"`
-		SyncAggregate          *SyncAggregate          `json:"sync_aggregate,omitempty"`
-		ExecutionPayloadHeader *ExecutionPayloadHeader `json:"execution_payload_header,omitempty"`
+		RandaoReveal           hexutil.Bytes           `json:"randao_reveal"`
+		Eth1Data               *Eth1Data               `json:"eth1_data"`
+		Graffiti               hexutil.Bytes           `json:"graffiti"`
+		ProposerSlashings      []*ProposerSlashing     `json:"proposer_slashings"`
+		AttesterSlashings      []*AttesterSlashing     `json:"attester_slashings"`
+		Attestations           []*Attestation          `json:"attestations"`
+		Deposits               []*Deposit              `json:"deposits"`
+		VoluntaryExits         []*SignedVoluntaryExit  `json:"voluntary_exits"`
+		SyncAggregate          *SyncAggregate          `json:"sync_aggregate"`
+		ExecutionPayloadHeader *ExecutionPayloadHeader `json:"execution_payload_header"`
 	}{
 		RandaoReveal:           b.RandaoReveal,
 		Eth1Data:               &Eth1Data{b.BlindedBeaconBlockBodyBellatrix.Eth1Data},
--- a/api/client/builder/types_test.go
+++ b/api/client/builder/types_test.go
@@ -187,8 +187,10 @@ func TestExecutionHeaderResponseUnmarshal(t *testing.T) {
 }

 func TestExecutionHeaderResponseToProto(t *testing.T) {
-	bfpg := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
-	v := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+	bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
+	v, err := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
 	hr := &ExecHeaderResponse{}
 	require.NoError(t, json.Unmarshal([]byte(testExampleHeaderResponse), hr))
 	p, err := hr.ToProto()
@@ -373,7 +375,8 @@ func TestExecutionPayloadResponseToProto(t *testing.T) {
 	require.NoError(t, err)
 	txList := [][]byte{tx}

-	bfpg := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
 	expected := &v1.ExecutionPayload{
 		ParentHash:    parentHash,
 		FeeRecipient:  feeRecipient,
@@ -581,7 +584,8 @@ func TestProposerSlashings(t *testing.T) {
 }

 func pbExecutionPayloadHeader(t *testing.T) *v1.ExecutionPayloadHeader {
-	bfpg := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+	require.NoError(t, err)
 	return &v1.ExecutionPayloadHeader{
 		ParentHash:       ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
 		FeeRecipient:     ezDecode(t, "0xabcf8e0d4e9587369b2301d0790347320302cc09"),
@@ -661,6 +665,49 @@ func TestMathBigUnmarshal(t *testing.T) {
 	require.NoError(t, u256.UnmarshalText([]byte("452312848583266388373324160190187140051835877600158453279131187530910662656")))
 }

+func TestIsValidUint256(t *testing.T) {
+	value, ok := new(big.Int), false
+
+	// negative uint256.max - 1
+	_, ok = value.SetString("-10000000000000000000000000000000000000000000000000000000000000000", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, 257, value.BitLen())
+	require.Equal(t, false, isValidUint256(value))
+
+	// negative uint256.max
+	_, ok = value.SetString("-ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, 256, value.BitLen())
+	require.Equal(t, false, isValidUint256(value))
+
+	// negative number
+	_, ok = value.SetString("-1", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, false, isValidUint256(value))
+
+	// uint256.min
+	_, ok = value.SetString("0", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, true, isValidUint256(value))
+
+	// positive number
+	_, ok = value.SetString("1", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, true, isValidUint256(value))
+
+	// uint256.max
+	_, ok = value.SetString("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, 256, value.BitLen())
+	require.Equal(t, true, isValidUint256(value))
+
+	// uint256.max + 1
+	_, ok = value.SetString("10000000000000000000000000000000000000000000000000000000000000000", 16)
+	require.Equal(t, true, ok)
+	require.Equal(t, 257, value.BitLen())
+	require.Equal(t, false, isValidUint256(value))
+}
+
 func TestUint256Unmarshal(t *testing.T) {
 	base10 := "452312848583266388373324160190187140051835877600158453279131187530910662656"
 	bi := new(big.Int)
@@ -677,6 +724,36 @@ func TestUint256Unmarshal(t *testing.T) {
 	require.Equal(t, expected, string(m))
 }

+func TestUint256UnmarshalNegative(t *testing.T) {
+	m := "-1"
+	var value Uint256
+	err := value.UnmarshalText([]byte(m))
+	require.ErrorContains(t, "unable to decode into Uint256", err)
+}
+
+func TestUint256UnmarshalMin(t *testing.T) {
+	m := "0"
+	var value Uint256
+	err := value.UnmarshalText([]byte(m))
+	require.NoError(t, err)
+}
+
+func TestUint256UnmarshalMax(t *testing.T) {
+	// 2**256-1 (uint256.max)
+	m := "115792089237316195423570985008687907853269984665640564039457584007913129639935"
+	var value Uint256
+	err := value.UnmarshalText([]byte(m))
+	require.NoError(t, err)
+}
+
+func TestUint256UnmarshalTooBig(t *testing.T) {
+	// 2**256 (one more than uint256.max)
+	m := "115792089237316195423570985008687907853269984665640564039457584007913129639936"
+	var value Uint256
+	err := value.UnmarshalText([]byte(m))
+	require.ErrorContains(t, "unable to decode into Uint256", err)
+}
+
 func TestMarshalBlindedBeaconBlockBodyBellatrix(t *testing.T) {
 	expected, err := os.ReadFile("testdata/blinded-block.json")
 	require.NoError(t, err)
@@ -708,10 +785,12 @@ func TestMarshalBlindedBeaconBlockBodyBellatrix(t *testing.T) {

 func TestRoundTripUint256(t *testing.T) {
 	vs := "4523128485832663883733241601901871400518358776001584532791311875309106626"
-	u := stringToUint256(vs)
+	u, err := stringToUint256(vs)
+	require.NoError(t, err)
 	sb := u.SSZBytes()
 	require.Equal(t, 32, len(sb))
-	uu := sszBytesToUint256(sb)
+	uu, err := sszBytesToUint256(sb)
+	require.NoError(t, err)
 	require.Equal(t, true, bytes.Equal(u.SSZBytes(), uu.SSZBytes()))
 	require.Equal(t, vs, uu.String())
 }
--- a/async/multilock.go
+++ b/async/multilock.go
@@ -3,7 +3,9 @@ Copyright 2017 Albert Tedja
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
-    http://www.apache.org/licenses/LICENSE-2.0
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
--- a/async/multilock_test.go
+++ b/async/multilock_test.go
@@ -3,7 +3,9 @@ Copyright 2017 Albert Tedja
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
-    http://www.apache.org/licenses/LICENSE-2.0
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
--- a/beacon-chain/blockchain/BUILD.bazel
+++ b/beacon-chain/blockchain/BUILD.bazel
@@ -51,9 +51,9 @@ go_library(
        "//beacon-chain/execution:go_default_library",
        "//beacon-chain/forkchoice:go_default_library",
        "//beacon-chain/forkchoice/doubly-linked-tree:go_default_library",
-        "//beacon-chain/forkchoice/protoarray:go_default_library",
        "//beacon-chain/forkchoice/types:go_default_library",
        "//beacon-chain/operations/attestations:go_default_library",
+        "//beacon-chain/operations/blstoexec:go_default_library",
        "//beacon-chain/operations/slashings:go_default_library",
        "//beacon-chain/operations/voluntaryexits:go_default_library",
        "//beacon-chain/p2p:go_default_library",
@@ -132,9 +132,8 @@ go_test(
        "//beacon-chain/execution/testing:go_default_library",
        "//beacon-chain/forkchoice/types:go_default_library",
        "//beacon-chain/p2p:go_default_library",
+        "//beacon-chain/state/state-native:go_default_library",
        "//beacon-chain/state/stateutil:go_default_library",
-        "//beacon-chain/state/v1:go_default_library",
-        "//beacon-chain/state/v3:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
--- a/beacon-chain/blockchain/chain_info.go
+++ b/beacon-chain/blockchain/chain_info.go
@@ -5,10 +5,10 @@ import (
 	"context"
 	"time"

+	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
@@ -314,7 +314,7 @@ func (s *Service) IsOptimistic(ctx context.Context) (bool, error) {
 	if err == nil {
 		return optimistic, nil
 	}
-	if err != protoarray.ErrUnknownNodeRoot && err != doublylinkedtree.ErrNilNode {
+	if !errors.Is(err, doublylinkedtree.ErrNilNode) {
 		return true, err
 	}
 	// If fockchoice does not have the headroot, then the node is considered
@@ -338,7 +338,7 @@ func (s *Service) IsOptimisticForRoot(ctx context.Context, root [32]byte) (bool,
 	if err == nil {
 		return optimistic, nil
 	}
-	if err != protoarray.ErrUnknownNodeRoot && err != doublylinkedtree.ErrNilNode {
+	if !errors.Is(err, doublylinkedtree.ErrNilNode) {
 		return false, err
 	}
 	// if the requested root is the headroot and the root is not found in
--- a/beacon-chain/blockchain/chain_info_norace_test.go
+++ b/beacon-chain/blockchain/chain_info_norace_test.go
@@ -5,6 +5,7 @@ import (
 	"testing"

 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -32,7 +33,7 @@ func TestHeadSlot_DataRace(t *testing.T) {
 func TestHeadRoot_DataRace(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	s := &Service{
-		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
+		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB, doublylinkedtree.New())},
 		head: &head{root: [32]byte{'A'}},
 	}
 	b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
@@ -54,7 +55,7 @@ func TestHeadBlock_DataRace(t *testing.T) {
 	wsb, err := blocks.NewSignedBeaconBlock(&ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Body: &ethpb.BeaconBlockBody{}}})
 	require.NoError(t, err)
 	s := &Service{
-		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
+		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB, doublylinkedtree.New())},
 		head: &head{block: wsb},
 	}
 	b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
@@ -74,7 +75,7 @@ func TestHeadBlock_DataRace(t *testing.T) {
 func TestHeadState_DataRace(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	s := &Service{
-		cfg: &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
+		cfg: &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB, doublylinkedtree.New())},
 	}
 	b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
 	require.NoError(t, err)
--- a/beacon-chain/blockchain/chain_info_test.go
+++ b/beacon-chain/blockchain/chain_info_test.go
@@ -7,12 +7,10 @@ import (

 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
-	v3 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v3"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
@@ -61,7 +59,7 @@ func prepareForkchoiceState(
 	}

 	base.BlockRoots[0] = append(base.BlockRoots[0], blockRoot[:]...)
-	st, err := v3.InitializeFromProto(base)
+	st, err := state_native.InitializeFromProtoBellatrix(base)
 	return st, blockRoot, err
 }

@@ -86,7 +84,7 @@ func TestFinalizedCheckpt_GenesisRootOk(t *testing.T) {
 	opts := []Option{
 		WithDatabase(beaconDB),
 		WithForkChoiceStore(fcs),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -111,7 +109,7 @@ func TestCurrentJustifiedCheckpt_CanRetrieve(t *testing.T) {
 	opts := []Option{
 		WithDatabase(beaconDB),
 		WithForkChoiceStore(fcs),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -125,7 +123,7 @@ func TestCurrentJustifiedCheckpt_CanRetrieve(t *testing.T) {

 func TestHeadSlot_CanRetrieve(t *testing.T) {
 	c := &Service{}
-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{})
 	require.NoError(t, err)
 	c.head = &head{slot: 100, state: s}
 	assert.Equal(t, types.Slot(100), c.HeadSlot())
@@ -138,7 +136,7 @@ func TestHeadRoot_CanRetrieve(t *testing.T) {
 	opts := []Option{
 		WithDatabase(beaconDB),
 		WithForkChoiceStore(fcs),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -157,7 +155,7 @@ func TestHeadRoot_UseDB(t *testing.T) {
 	opts := []Option{
 		WithDatabase(beaconDB),
 		WithForkChoiceStore(fcs),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -179,7 +177,7 @@ func TestHeadRoot_UseDB(t *testing.T) {
 func TestHeadBlock_CanRetrieve(t *testing.T) {
 	b := util.NewBeaconBlock()
 	b.Block.Slot = 1
-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{})
 	require.NoError(t, err)
 	wsb, err := blocks.NewSignedBeaconBlock(b)
 	require.NoError(t, err)
@@ -194,13 +192,13 @@ func TestHeadBlock_CanRetrieve(t *testing.T) {
 }

 func TestHeadState_CanRetrieve(t *testing.T) {
-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{Slot: 2, GenesisValidatorsRoot: params.BeaconConfig().ZeroHash[:]})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{Slot: 2, GenesisValidatorsRoot: params.BeaconConfig().ZeroHash[:]})
 	require.NoError(t, err)
 	c := &Service{}
 	c.head = &head{state: s}
 	headState, err := c.HeadState(context.Background())
 	require.NoError(t, err)
-	assert.DeepEqual(t, headState.InnerStateUnsafe(), s.InnerStateUnsafe(), "Incorrect head state received")
+	assert.DeepEqual(t, headState.ToProtoUnsafe(), s.ToProtoUnsafe(), "Incorrect head state received")
 }

 func TestGenesisTime_CanRetrieve(t *testing.T) {
@@ -211,7 +209,7 @@ func TestGenesisTime_CanRetrieve(t *testing.T) {

 func TestCurrentFork_CanRetrieve(t *testing.T) {
 	f := &ethpb.Fork{Epoch: 999}
-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{Fork: f})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{Fork: f})
 	require.NoError(t, err)
 	c := &Service{}
 	c.head = &head{state: s}
@@ -236,7 +234,7 @@ func TestGenesisValidatorsRoot_CanRetrieve(t *testing.T) {
 	c := &Service{}
 	assert.Equal(t, [32]byte{}, c.GenesisValidatorsRoot(), "Did not get correct genesis validators root")

-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{GenesisValidatorsRoot: []byte{'a'}})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{GenesisValidatorsRoot: []byte{'a'}})
 	require.NoError(t, err)
 	c.head = &head{state: s}
 	assert.Equal(t, [32]byte{'a'}, c.GenesisValidatorsRoot(), "Did not get correct genesis validators root")
@@ -250,7 +248,7 @@ func TestHeadETH1Data_Nil(t *testing.T) {

 func TestHeadETH1Data_CanRetrieve(t *testing.T) {
 	d := &ethpb.Eth1Data{DepositCount: 999}
-	s, err := v1.InitializeFromProto(&ethpb.BeaconState{Eth1Data: d})
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{Eth1Data: d})
 	require.NoError(t, err)
 	c := &Service{}
 	c.head = &head{state: s}
@@ -306,31 +304,6 @@ func TestService_HeadGenesisValidatorsRoot(t *testing.T) {
 	root = c.HeadGenesisValidatorsRoot()
 	require.DeepEqual(t, root[:], s.GenesisValidatorsRoot())
 }
-func TestService_ChainHeads_ProtoArray(t *testing.T) {
-	ctx := context.Background()
-	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New()}}
-	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)
-	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, 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, 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, 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, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-
-	roots, slots := c.ChainHeads()
-	require.DeepEqual(t, [][32]byte{{'c'}, {'d'}, {'e'}}, roots)
-	require.DeepEqual(t, []types.Slot{102, 103, 104}, slots)
-}

 //
 //  A <- B <- C
@@ -338,7 +311,7 @@ func TestService_ChainHeads_ProtoArray(t *testing.T) {
 //    \    ---------- E
 //     ---------- D

-func TestService_ChainHeads_DoublyLinkedTree(t *testing.T) {
+func TestService_ChainHeads(t *testing.T) {
 	ctx := context.Background()
 	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}}
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
@@ -430,29 +403,7 @@ func TestService_HeadValidatorIndexToPublicKeyNil(t *testing.T) {
 	require.Equal(t, [fieldparams.BLSPubkeyLength]byte{}, p)
 }

-func TestService_IsOptimistic_ProtoArray(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	cfg := params.BeaconConfig()
-	cfg.BellatrixForkEpoch = 0
-	params.OverrideBeaconConfig(cfg)
-
-	ctx := context.Background()
-	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New()}, head: &head{slot: 101, 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)
-	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, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-
-	opt, err := c.IsOptimistic(ctx)
-	require.NoError(t, err)
-	require.Equal(t, true, opt)
-}
-
-func TestService_IsOptimistic_DoublyLinkedTree(t *testing.T) {
+func TestService_IsOptimistic(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	cfg := params.BeaconConfig()
 	cfg.BellatrixForkEpoch = 0
@@ -482,24 +433,7 @@ func TestService_IsOptimisticBeforeBellatrix(t *testing.T) {
 	require.Equal(t, false, opt)
 }

-func TestService_IsOptimisticForRoot_ProtoArray(t *testing.T) {
-	ctx := context.Background()
-	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New()}, head: &head{slot: 101, 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)
-	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, err)
-	require.NoError(t, c.cfg.ForkChoiceStore.InsertNode(ctx, st, blkRoot))
-
-	opt, err := c.IsOptimisticForRoot(ctx, [32]byte{'a'})
-	require.NoError(t, err)
-	require.Equal(t, true, opt)
-}
-
-func TestService_IsOptimisticForRoot_DoublyLinkedTree(t *testing.T) {
+func TestService_IsOptimisticForRoot(t *testing.T) {
 	ctx := context.Background()
 	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New()}, head: &head{slot: 101, root: [32]byte{'b'}}}
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
@@ -516,66 +450,7 @@ func TestService_IsOptimisticForRoot_DoublyLinkedTree(t *testing.T) {
 	require.Equal(t, true, opt)
 }

-func TestService_IsOptimisticForRoot_DB_ProtoArray(t *testing.T) {
-	beaconDB := testDB.SetupDB(t)
-	ctx := context.Background()
-	c := &Service{cfg: &config{BeaconDB: beaconDB, ForkChoiceStore: protoarray.New()}, head: &head{slot: 101, root: [32]byte{'b'}}}
-	c.head = &head{root: params.BeaconConfig().ZeroHash}
-	b := util.NewBeaconBlock()
-	b.Block.Slot = 10
-	br, err := b.Block.HashTreeRoot()
-	require.NoError(t, err)
-	util.SaveBlock(t, context.Background(), beaconDB, b)
-	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: br[:], Slot: 10}))
-
-	optimisticBlock := util.NewBeaconBlock()
-	optimisticBlock.Block.Slot = 97
-	optimisticRoot, err := optimisticBlock.Block.HashTreeRoot()
-	require.NoError(t, err)
-	util.SaveBlock(t, context.Background(), beaconDB, optimisticBlock)
-
-	validatedBlock := util.NewBeaconBlock()
-	validatedBlock.Block.Slot = 9
-	validatedRoot, err := validatedBlock.Block.HashTreeRoot()
-	require.NoError(t, err)
-	util.SaveBlock(t, context.Background(), beaconDB, validatedBlock)
-
-	validatedCheckpoint := &ethpb.Checkpoint{Root: br[:]}
-	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, validatedCheckpoint))
-
-	_, err = c.IsOptimisticForRoot(ctx, optimisticRoot)
-	require.ErrorContains(t, "nil summary returned from the DB", err)
-
-	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: optimisticRoot[:], Slot: 11}))
-	optimistic, err := c.IsOptimisticForRoot(ctx, optimisticRoot)
-	require.NoError(t, err)
-	require.Equal(t, true, optimistic)
-
-	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: validatedRoot[:], Slot: 9}))
-	cp := &ethpb.Checkpoint{
-		Epoch: 1,
-		Root:  validatedRoot[:],
-	}
-	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, validatedRoot))
-	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, cp))
-
-	validated, err := c.IsOptimisticForRoot(ctx, validatedRoot)
-	require.NoError(t, err)
-	require.Equal(t, false, validated)
-
-	// Before the first finalized epoch, finalized root could be zeros.
-	validatedCheckpoint = &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, br))
-	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: params.BeaconConfig().ZeroHash[:], Slot: 10}))
-	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, validatedCheckpoint))
-
-	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: optimisticRoot[:], Slot: 11}))
-	optimistic, err = c.IsOptimisticForRoot(ctx, optimisticRoot)
-	require.NoError(t, err)
-	require.Equal(t, true, optimistic)
-}
-
-func TestService_IsOptimisticForRoot_DB_DoublyLinkedTree(t *testing.T) {
+func TestService_IsOptimisticForRoot_DB(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	ctx := context.Background()
 	c := &Service{cfg: &config{BeaconDB: beaconDB, ForkChoiceStore: doublylinkedtree.New()}, head: &head{slot: 101, root: [32]byte{'b'}}}
--- a/beacon-chain/blockchain/error.go
+++ b/beacon-chain/blockchain/error.go
@@ -14,7 +14,7 @@ var (
 	// errNilFinalizedCheckpoint is returned when a nil finalized checkpt is returned from a state.
 	errNilFinalizedCheckpoint = errors.New("nil finalized checkpoint returned from state")
 	// errNilJustifiedCheckpoint is returned when a nil justified checkpt is returned from a state.
-	errNilJustifiedCheckpoint = errors.New("nil finalized checkpoint returned from state")
+	errNilJustifiedCheckpoint = errors.New("nil justified checkpoint returned from state")
 	// errInvalidNilSummary is returned when a nil summary is returned from the DB.
 	errInvalidNilSummary = errors.New("nil summary returned from the DB")
 	// errWrongBlockCount is returned when the wrong number of blocks or block roots is used
--- a/beacon-chain/blockchain/execution_engine.go
+++ b/beacon-chain/blockchain/execution_engine.go
@@ -70,7 +70,6 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *notifyForkcho
 	hasAttr, attr, proposerId, err := s.getPayloadAttribute(ctx, arg.headState, nextSlot)
 	if err != nil {
 		log.WithError(err).Error("Could not get head payload attribute")
-		return nil, nil
 	}

 	payloadID, lastValidHash, err := s.cfg.ExecutionEngineCaller.ForkchoiceUpdated(ctx, fcs, attr)
@@ -83,18 +82,14 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *notifyForkcho
 				"headPayloadBlockHash":      fmt.Sprintf("%#x", bytesutil.Trunc(headPayload.BlockHash())),
 				"finalizedPayloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(finalizedHash[:])),
 			}).Info("Called fork choice updated with optimistic block")
-			err := s.optimisticCandidateBlock(ctx, headBlk)
-			if err != nil {
-				log.WithError(err).Error("Optimistic block failed to be candidate")
-			}
 			return payloadID, nil
 		case execution.ErrInvalidPayloadStatus:
-			newPayloadInvalidNodeCount.Inc()
+			forkchoiceUpdatedInvalidNodeCount.Inc()
 			headRoot := arg.headRoot
 			if len(lastValidHash) == 0 {
 				lastValidHash = defaultLatestValidHash
 			}
-			invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, headRoot, bytesutil.ToBytes32(headBlk.ParentRoot()), bytesutil.ToBytes32(lastValidHash))
+			invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, headRoot, headBlk.ParentRoot(), bytesutil.ToBytes32(lastValidHash))
 			if err != nil {
 				log.WithError(err).Error("Could not set head root to invalid")
 				return nil, nil
@@ -107,9 +102,9 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *notifyForkcho
 			r, err := s.cfg.ForkChoiceStore.Head(ctx, s.justifiedBalances.balances)
 			if err != nil {
 				log.WithFields(logrus.Fields{
-					"slot":         headBlk.Slot(),
-					"blockRoot":    fmt.Sprintf("%#x", bytesutil.Trunc(headRoot[:])),
-					"invalidCount": len(invalidRoots),
+					"slot":                 headBlk.Slot(),
+					"blockRoot":            fmt.Sprintf("%#x", bytesutil.Trunc(headRoot[:])),
+					"invalidChildrenCount": len(invalidRoots),
 				}).Warn("Pruned invalid blocks, could not update head root")
 				return nil, invalidBlock{error: ErrInvalidPayload, root: arg.headRoot, invalidAncestorRoots: invalidRoots}
 			}
@@ -137,10 +132,10 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *notifyForkcho
 			}

 			log.WithFields(logrus.Fields{
-				"slot":         headBlk.Slot(),
-				"blockRoot":    fmt.Sprintf("%#x", bytesutil.Trunc(headRoot[:])),
-				"invalidCount": len(invalidRoots),
-				"newHeadRoot":  fmt.Sprintf("%#x", bytesutil.Trunc(r[:])),
+				"slot":                 headBlk.Slot(),
+				"blockRoot":            fmt.Sprintf("%#x", bytesutil.Trunc(headRoot[:])),
+				"invalidChildrenCount": len(invalidRoots),
+				"newHeadRoot":          fmt.Sprintf("%#x", bytesutil.Trunc(r[:])),
 			}).Warn("Pruned invalid blocks")
 			return pid, invalidBlock{error: ErrInvalidPayload, root: arg.headRoot, invalidAncestorRoots: invalidRoots}

@@ -184,10 +179,10 @@ func (s *Service) getPayloadHash(ctx context.Context, root []byte) ([32]byte, er
 	return bytesutil.ToBytes32(payload.BlockHash()), nil
 }

-// notifyForkchoiceUpdate signals execution engine on a new payload.
+// notifyNewPayload signals execution engine on a new payload.
 // It returns true if the EL has returned VALID for the block
 func (s *Service) notifyNewPayload(ctx context.Context, postStateVersion int,
-	postStateHeader *enginev1.ExecutionPayloadHeader, blk interfaces.SignedBeaconBlock) (bool, error) {
+	postStateHeader interfaces.ExecutionData, blk interfaces.SignedBeaconBlock) (bool, error) {
 	ctx, span := trace.StartSpan(ctx, "blockChain.notifyNewPayload")
 	defer span.End()

@@ -222,14 +217,14 @@ func (s *Service) notifyNewPayload(ctx context.Context, postStateVersion int,
 			"slot":             blk.Block().Slot(),
 			"payloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash())),
 		}).Info("Called new payload with optimistic block")
-		return false, s.optimisticCandidateBlock(ctx, blk.Block())
+		return false, nil
 	case execution.ErrInvalidPayloadStatus:
 		newPayloadInvalidNodeCount.Inc()
 		root, err := blk.Block().HashTreeRoot()
 		if err != nil {
 			return false, err
 		}
-		invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, root, bytesutil.ToBytes32(blk.Block().ParentRoot()), bytesutil.ToBytes32(lastValidHash))
+		invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, root, blk.Block().ParentRoot(), bytesutil.ToBytes32(lastValidHash))
 		if err != nil {
 			return false, err
 		}
@@ -237,9 +232,9 @@ func (s *Service) notifyNewPayload(ctx context.Context, postStateVersion int,
 			return false, err
 		}
 		log.WithFields(logrus.Fields{
-			"slot":         blk.Block().Slot(),
-			"blockRoot":    fmt.Sprintf("%#x", root),
-			"invalidCount": len(invalidRoots),
+			"slot":                 blk.Block().Slot(),
+			"blockRoot":            fmt.Sprintf("%#x", root),
+			"invalidChildrenCount": len(invalidRoots),
 		}).Warn("Pruned invalid blocks")
 		return false, invalidBlock{
 			invalidAncestorRoots: invalidRoots,
@@ -253,37 +248,6 @@ func (s *Service) notifyNewPayload(ctx context.Context, postStateVersion int,
 	}
 }

-// optimisticCandidateBlock returns an error if this block can't be optimistically synced.
-// It replaces boolean in spec code with `errNotOptimisticCandidate`.
-//
-// Spec pseudocode definition:
-// def is_optimistic_candidate_block(opt_store: OptimisticStore, current_slot: Slot, block: BeaconBlock) -> bool:
-//    if is_execution_block(opt_store.blocks[block.parent_root]):
-//        return True
-//
-//    if block.slot + SAFE_SLOTS_TO_IMPORT_OPTIMISTICALLY <= current_slot:
-//        return True
-//
-//    return False
-func (s *Service) optimisticCandidateBlock(ctx context.Context, blk interfaces.BeaconBlock) error {
-	if blk.Slot()+params.BeaconConfig().SafeSlotsToImportOptimistically <= s.CurrentSlot() {
-		return nil
-	}
-	parent, err := s.getBlock(ctx, bytesutil.ToBytes32(blk.ParentRoot()))
-	if err != nil {
-		return err
-	}
-	parentIsExecutionBlock, err := blocks.IsExecutionBlock(parent.Block().Body())
-	if err != nil {
-		return err
-	}
-	if parentIsExecutionBlock {
-		return nil
-	}
-
-	return errNotOptimisticCandidate
-}
-
 // getPayloadAttributes returns the payload attributes for the given state and slot.
 // The attribute is required to initiate a payload build process in the context of an `engine_forkchoiceUpdated` call.
 func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState, slot types.Slot) (bool, *enginev1.PayloadAttributes, types.ValidatorIndex, error) {
--- a/beacon-chain/blockchain/execution_engine_test.go
+++ b/beacon-chain/blockchain/execution_engine_test.go
@@ -13,9 +13,9 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/execution"
 	mockExecution "github.com/prysmaticlabs/prysm/v3/beacon-chain/execution/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	bstate "github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
@@ -31,8 +31,7 @@ import (
 	logTest "github.com/sirupsen/logrus/hooks/test"
 )

-func Test_NotifyForkchoiceUpdate(t *testing.T) {
-	params.BeaconConfig().SafeSlotsToImportOptimistically = 0
+func Test_NotifyForkchoiceUpdate_GetPayloadAttrErrorCanContinue(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 	altairBlk := util.SaveBlock(t, ctx, beaconDB, util.NewBeaconBlockAltair())
@@ -44,16 +43,80 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 		WithProposerIdsCache(cache.NewProposerPayloadIDsCache()),
 	}
 	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
 	st, _ := util.DeterministicGenesisState(t, 10)
 	service.head = &head{
 		state: st,
 	}
+
+	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
+	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
+	state, blkRoot, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
+	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
+	state, blkRoot, err = prepareForkchoiceState(ctx, 1, altairBlkRoot, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, err)
+	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
+	state, blkRoot, err = prepareForkchoiceState(ctx, 2, bellatrixBlkRoot, altairBlkRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
+	require.NoError(t, err)
+	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
+
+	b, err := consensusblocks.NewBeaconBlock(&ethpb.BeaconBlockBellatrix{
+		Body: &ethpb.BeaconBlockBodyBellatrix{
+			ExecutionPayload: &v1.ExecutionPayload{},
+		},
+	})
+	require.NoError(t, err)
+
+	pid := &v1.PayloadIDBytes{1}
+	service.cfg.ExecutionEngineCaller = &mockExecution.EngineClient{PayloadIDBytes: pid}
+	st, _ = util.DeterministicGenesisState(t, 1)
+	require.NoError(t, beaconDB.SaveState(ctx, st, bellatrixBlkRoot))
+	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, bellatrixBlkRoot))
+
+	// Intentionally generate a bad state such that `hash_tree_root` fails during `process_slot`
+	s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{})
+	require.NoError(t, err)
+	arg := &notifyForkchoiceUpdateArg{
+		headState: s,
+		headRoot:  [32]byte{},
+		headBlock: b,
+	}
+
+	service.cfg.ProposerSlotIndexCache.SetProposerAndPayloadIDs(1, 0, [8]byte{}, [32]byte{})
+	got, err := service.notifyForkchoiceUpdate(ctx, arg)
+	require.NoError(t, err)
+	require.DeepEqual(t, got, pid) // We still get a payload ID even though the state is bad. This means it returns until the end.
+}
+
+func Test_NotifyForkchoiceUpdate(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	altairBlk := util.SaveBlock(t, ctx, beaconDB, util.NewBeaconBlockAltair())
+	altairBlkRoot, err := altairBlk.Block().HashTreeRoot()
+	require.NoError(t, err)
+	bellatrixBlk := util.SaveBlock(t, ctx, beaconDB, util.NewBeaconBlockBellatrix())
+	bellatrixBlkRoot, err := bellatrixBlk.Block().HashTreeRoot()
+	require.NoError(t, err)
+	fcs := doublylinkedtree.New()
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stategen.New(beaconDB, fcs)),
+		WithForkChoiceStore(fcs),
+		WithProposerIdsCache(cache.NewProposerPayloadIDsCache()),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+	st, _ := util.DeterministicGenesisState(t, 10)
+	service.head = &head{
+		state: st,
+	}
+
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	state, blkRoot, err := prepareForkchoiceState(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, ojc, ofc)
@@ -199,151 +262,6 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 	}
 }

-//
-//
-//  A <- B <- C <- D
-//       \
-//         ---------- E <- F
-//                     \
-//                       ------ G
-// D is the current head, attestations for F and G come late, both are invalid.
-// We switch recursively to F then G and finally to D.
-//
-// We test:
-// 1. forkchoice removes blocks F and G from the forkchoice implementation
-// 2. forkchoice removes the weights of these blocks
-// 3. the blockchain package calls fcu to obtain heads G -> F -> D.
-
-func Test_NotifyForkchoiceUpdateRecursive_Protoarray(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	// Prepare blocks
-	ba := util.NewBeaconBlockBellatrix()
-	ba.Block.Body.ExecutionPayload.BlockNumber = 1
-	wba := util.SaveBlock(t, ctx, beaconDB, ba)
-	bra, err := wba.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	bb := util.NewBeaconBlockBellatrix()
-	bb.Block.Body.ExecutionPayload.BlockNumber = 2
-	wbb := util.SaveBlock(t, ctx, beaconDB, bb)
-	brb, err := wbb.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	bc := util.NewBeaconBlockBellatrix()
-	bc.Block.Body.ExecutionPayload.BlockNumber = 3
-	wbc := util.SaveBlock(t, ctx, beaconDB, bc)
-	brc, err := wbc.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	bd := util.NewBeaconBlockBellatrix()
-	pd := [32]byte{'D'}
-	bd.Block.Body.ExecutionPayload.BlockHash = pd[:]
-	bd.Block.Body.ExecutionPayload.BlockNumber = 4
-	wbd := util.SaveBlock(t, ctx, beaconDB, bd)
-	brd, err := wbd.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	be := util.NewBeaconBlockBellatrix()
-	pe := [32]byte{'E'}
-	be.Block.Body.ExecutionPayload.BlockHash = pe[:]
-	be.Block.Body.ExecutionPayload.BlockNumber = 5
-	wbe := util.SaveBlock(t, ctx, beaconDB, be)
-	bre, err := wbe.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	bf := util.NewBeaconBlockBellatrix()
-	pf := [32]byte{'F'}
-	bf.Block.Body.ExecutionPayload.BlockHash = pf[:]
-	bf.Block.Body.ExecutionPayload.BlockNumber = 6
-	bf.Block.ParentRoot = bre[:]
-	wbf := util.SaveBlock(t, ctx, beaconDB, bf)
-	brf, err := wbf.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	bg := util.NewBeaconBlockBellatrix()
-	bg.Block.Body.ExecutionPayload.BlockNumber = 7
-	pg := [32]byte{'G'}
-	bg.Block.Body.ExecutionPayload.BlockHash = pg[:]
-	bg.Block.ParentRoot = bre[:]
-	wbg := util.SaveBlock(t, ctx, beaconDB, bg)
-	brg, err := wbg.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	// Insert blocks into forkchoice
-	service := setupBeaconChain(t, beaconDB)
-	fcs := protoarray.New()
-	service.cfg.ForkChoiceStore = fcs
-	service.cfg.ProposerSlotIndexCache = cache.NewProposerPayloadIDsCache()
-
-	service.justifiedBalances.balances = []uint64{50, 100, 200}
-	require.NoError(t, err)
-	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	state, blkRoot, err := prepareForkchoiceState(ctx, 1, bra, [32]byte{}, [32]byte{'A'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 2, brb, bra, [32]byte{'B'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 3, brc, brb, [32]byte{'C'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 4, brd, brc, [32]byte{'D'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 5, bre, brb, [32]byte{'E'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 6, brf, bre, [32]byte{'F'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-	state, blkRoot, err = prepareForkchoiceState(ctx, 7, brg, bre, [32]byte{'G'}, ojc, ofc)
-	require.NoError(t, err)
-	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
-
-	// Insert Attestations to D, F and G so that they have higher weight than D
-	// Ensure G is head
-	fcs.ProcessAttestation(ctx, []uint64{0}, brd, 1)
-	fcs.ProcessAttestation(ctx, []uint64{1}, brf, 1)
-	fcs.ProcessAttestation(ctx, []uint64{2}, brg, 1)
-	jc := &forkchoicetypes.Checkpoint{Epoch: 0, Root: bra}
-	require.NoError(t, fcs.UpdateJustifiedCheckpoint(jc))
-	headRoot, err := fcs.Head(ctx, []uint64{50, 100, 200})
-	require.NoError(t, err)
-	require.Equal(t, brg, headRoot)
-
-	// Prepare Engine Mock to return invalid unless head is D, LVH =  E
-	service.cfg.ExecutionEngineCaller = &mockExecution.EngineClient{ErrForkchoiceUpdated: execution.ErrInvalidPayloadStatus, ForkChoiceUpdatedResp: pe[:], OverrideValidHash: [32]byte{'D'}}
-	st, _ := util.DeterministicGenesisState(t, 1)
-	service.head = &head{
-		state: st,
-		block: wba,
-	}
-
-	require.NoError(t, beaconDB.SaveState(ctx, st, bra))
-	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, bra))
-	a := &notifyForkchoiceUpdateArg{
-		headState: st,
-		headBlock: wbg.Block(),
-		headRoot:  brg,
-	}
-	_, err = service.notifyForkchoiceUpdate(ctx, a)
-	require.Equal(t, true, IsInvalidBlock(err))
-	require.Equal(t, brf, InvalidBlockRoot(err))
-
-	// Ensure Head is D
-	headRoot, err = fcs.Head(ctx, service.justifiedBalances.balances)
-	require.NoError(t, err)
-	require.Equal(t, brd, headRoot)
-
-	// Ensure F and G where removed but their parent E wasn't
-	require.Equal(t, false, fcs.HasNode(brf))
-	require.Equal(t, false, fcs.HasNode(brg))
-	require.Equal(t, true, fcs.HasNode(bre))
-}
-
 func Test_NotifyForkchoiceUpdate_NIlLVH(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
@@ -578,7 +496,7 @@ func Test_NotifyNewPayload(t *testing.T) {
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	phase0State, _ := util.DeterministicGenesisState(t, 1)
@@ -824,7 +742,7 @@ func Test_NotifyNewPayload_SetOptimisticToValid(t *testing.T) {
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	bellatrixState, _ := util.DeterministicGenesisStateBellatrix(t, 2)
@@ -862,161 +780,12 @@ func Test_NotifyNewPayload_SetOptimisticToValid(t *testing.T) {
 	require.Equal(t, true, validated)
 }

-func Test_IsOptimisticCandidateBlock(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	params.OverrideBeaconConfig(params.MainnetConfig())
-
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-	fcs := doublylinkedtree.New()
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(fcs),
-	}
-
-	service, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-
-	params.BeaconConfig().SafeSlotsToImportOptimistically = 128
-	service.genesisTime = time.Now().Add(-time.Second * 12 * 2 * 128)
-
-	parentBlk := util.NewBeaconBlockBellatrix()
-	wrappedParentBlock, err := consensusblocks.NewSignedBeaconBlock(parentBlk)
-	require.NoError(t, err)
-	parentRoot, err := wrappedParentBlock.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	tests := []struct {
-		name      string
-		blk       interfaces.BeaconBlock
-		justified interfaces.SignedBeaconBlock
-		err       error
-	}{
-		{
-			name: "deep block",
-			blk: func(tt *testing.T) interfaces.BeaconBlock {
-				blk := util.NewBeaconBlockBellatrix()
-				blk.Block.Slot = 1
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewBeaconBlock(blk.Block)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			justified: func(tt *testing.T) interfaces.SignedBeaconBlock {
-				blk := util.NewBeaconBlockBellatrix()
-				blk.Block.Slot = 32
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewSignedBeaconBlock(blk)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			err: nil,
-		},
-		{
-			name: "shallow block, Altair justified chkpt",
-			blk: func(tt *testing.T) interfaces.BeaconBlock {
-				blk := util.NewBeaconBlockAltair()
-				blk.Block.Slot = 200
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewBeaconBlock(blk.Block)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			justified: func(tt *testing.T) interfaces.SignedBeaconBlock {
-				blk := util.NewBeaconBlockAltair()
-				blk.Block.Slot = 32
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewSignedBeaconBlock(blk)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			err: errNotOptimisticCandidate,
-		},
-		{
-			name: "shallow block, Bellatrix justified chkpt without execution",
-			blk: func(tt *testing.T) interfaces.BeaconBlock {
-				blk := util.NewBeaconBlockBellatrix()
-				blk.Block.Slot = 200
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewBeaconBlock(blk.Block)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			justified: func(tt *testing.T) interfaces.SignedBeaconBlock {
-				blk := util.NewBeaconBlockBellatrix()
-				blk.Block.Slot = 32
-				blk.Block.ParentRoot = parentRoot[:]
-				wr, err := consensusblocks.NewSignedBeaconBlock(blk)
-				require.NoError(tt, err)
-				return wr
-			}(t),
-			err: errNotOptimisticCandidate,
-		},
-	}
-	for _, tt := range tests {
-		require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, tt.justified))
-		require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrappedParentBlock))
-
-		err = service.optimisticCandidateBlock(ctx, tt.blk)
-		if tt.err != nil {
-			require.Equal(t, tt.err.Error(), err.Error())
-		} else {
-			require.NoError(t, err)
-		}
-	}
-}
-
-func Test_IsOptimisticShallowExecutionParent(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	params.OverrideBeaconConfig(params.MainnetConfig())
-
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-	}
-
-	service, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-
-	params.BeaconConfig().SafeSlotsToImportOptimistically = 128
-	service.genesisTime = time.Now().Add(-time.Second * 12 * 2 * 128)
-	payload := &v1.ExecutionPayload{
-		ParentHash:    make([]byte, 32),
-		FeeRecipient:  make([]byte, 20),
-		StateRoot:     make([]byte, 32),
-		ReceiptsRoot:  make([]byte, 32),
-		LogsBloom:     make([]byte, 256),
-		PrevRandao:    make([]byte, 32),
-		BaseFeePerGas: bytesutil.PadTo([]byte{1, 2, 3, 4}, fieldparams.RootLength),
-		BlockHash:     make([]byte, 32),
-		BlockNumber:   100,
-	}
-	body := &ethpb.BeaconBlockBodyBellatrix{ExecutionPayload: payload}
-	b := &ethpb.BeaconBlockBellatrix{Body: body, Slot: 200}
-	rawSigned := &ethpb.SignedBeaconBlockBellatrix{Block: b}
-	blk := util.HydrateSignedBeaconBlockBellatrix(rawSigned)
-	wr := util.SaveBlock(t, ctx, service.cfg.BeaconDB, blk)
-	blkRoot, err := wr.Block().HashTreeRoot()
-	require.NoError(t, err)
-
-	childBlock := util.NewBeaconBlockBellatrix()
-	childBlock.Block.ParentRoot = blkRoot[:]
-	// shallow block
-	childBlock.Block.Slot = 201
-	wrappedChild := util.SaveBlock(t, ctx, service.cfg.BeaconDB, childBlock)
-	err = service.optimisticCandidateBlock(ctx, wrappedChild.Block())
-	require.NoError(t, err)
-}
-
 func Test_GetPayloadAttribute(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, doublylinkedtree.New())),
 		WithProposerIdsCache(cache.NewProposerPayloadIDsCache()),
 	}

@@ -1058,8 +827,8 @@ func Test_UpdateLastValidatedCheckpoint(t *testing.T) {

 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
-	stateGen := stategen.New(beaconDB)
 	fcs := doublylinkedtree.New()
+	stateGen := stategen.New(beaconDB, fcs)
 	opts := []Option{
 		WithDatabase(beaconDB),
 		WithStateGen(stateGen),
@@ -1155,15 +924,28 @@ func Test_UpdateLastValidatedCheckpoint(t *testing.T) {
 	require.Equal(t, false, optimistic)
 	require.DeepEqual(t, validCheckpoint.Root, cp.Root)
 	require.Equal(t, validCheckpoint.Epoch, cp.Epoch)
+
+	// Checkpoint with a lower epoch
+	oldCp, err := service.cfg.BeaconDB.FinalizedCheckpoint(ctx)
+	require.NoError(t, err)
+	invalidCp := &ethpb.Checkpoint{
+		Epoch: oldCp.Epoch - 1,
+	}
+	// Nothing should happen as we no-op on an invalid checkpoint.
+	require.NoError(t, service.updateFinalized(ctx, invalidCp))
+	got, err := service.cfg.BeaconDB.FinalizedCheckpoint(ctx)
+	require.NoError(t, err)
+	require.DeepEqual(t, oldCp, got)
 }

 func TestService_removeInvalidBlockAndState(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
+	fc := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(doublylinkedtree.New()),
+		WithStateGen(stategen.New(beaconDB, fc)),
+		WithForkChoiceStore(fc),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -1212,10 +994,11 @@ func TestService_removeInvalidBlockAndState(t *testing.T) {
 func TestService_getPayloadHash(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
+	fc := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(doublylinkedtree.New()),
+		WithStateGen(stategen.New(beaconDB, fc)),
+		WithForkChoiceStore(fc),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
--- a/beacon-chain/blockchain/head.go
+++ b/beacon-chain/blockchain/head.go
@@ -17,6 +17,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/interfaces"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
+	"github.com/prysmaticlabs/prysm/v3/math"
 	ethpbv1 "github.com/prysmaticlabs/prysm/v3/proto/eth/v1"
 	"github.com/prysmaticlabs/prysm/v3/time/slots"
 	"github.com/sirupsen/logrus"
@@ -87,10 +88,10 @@ func (s *Service) saveHead(ctx context.Context, newHeadRoot [32]byte, headBlock
 		return nil
 	}

-	// A chain re-org occurred, so we fire an event notifying the rest of the services.
 	s.headLock.RLock()
 	oldHeadBlock, err := s.headBlock()
 	if err != nil {
+		s.headLock.RUnlock()
 		return errors.Wrap(err, "could not get old head block")
 	}
 	oldStateRoot := oldHeadBlock.Block().StateRoot()
@@ -98,12 +99,28 @@ func (s *Service) saveHead(ctx context.Context, newHeadRoot [32]byte, headBlock
 	headSlot := s.HeadSlot()
 	newHeadSlot := headBlock.Block().Slot()
 	newStateRoot := headBlock.Block().StateRoot()
-	if bytesutil.ToBytes32(headBlock.Block().ParentRoot()) != oldHeadRoot {
+
+	// A chain re-org occurred, so we fire an event notifying the rest of the services.
+	if headBlock.Block().ParentRoot() != oldHeadRoot {
+		commonRoot, forkSlot, err := s.ForkChoicer().CommonAncestor(ctx, oldHeadRoot, newHeadRoot)
+		if err != nil {
+			log.WithError(err).Error("Could not find common ancestor root")
+			commonRoot = params.BeaconConfig().ZeroHash
+		}
+		dis := headSlot + newHeadSlot - 2*forkSlot
+		dep := math.Max(uint64(headSlot-forkSlot), uint64(newHeadSlot-forkSlot))
 		log.WithFields(logrus.Fields{
-			"newSlot": fmt.Sprintf("%d", newHeadSlot),
-			"oldSlot": fmt.Sprintf("%d", headSlot),
-		}).Debug("Chain reorg occurred")
-		absoluteSlotDifference := slots.AbsoluteValueSlotDifference(newHeadSlot, headSlot)
+			"newSlot":            fmt.Sprintf("%d", newHeadSlot),
+			"newRoot":            fmt.Sprintf("%#x", newHeadRoot),
+			"oldSlot":            fmt.Sprintf("%d", headSlot),
+			"oldRoot":            fmt.Sprintf("%#x", oldHeadRoot),
+			"commonAncestorRoot": fmt.Sprintf("%#x", commonRoot),
+			"distance":           dis,
+			"depth":              dep,
+		}).Info("Chain reorg occurred")
+		reorgDistance.Observe(float64(dis))
+		reorgDepth.Observe(float64(dep))
+
 		isOptimistic, err := s.IsOptimistic(ctx)
 		if err != nil {
 			return errors.Wrap(err, "could not check if node is optimistically synced")
@@ -112,11 +129,11 @@ func (s *Service) saveHead(ctx context.Context, newHeadRoot [32]byte, headBlock
 			Type: statefeed.Reorg,
 			Data: &ethpbv1.EventChainReorg{
 				Slot:                newHeadSlot,
-				Depth:               absoluteSlotDifference,
+				Depth:               math.Max(uint64(headSlot-forkSlot), uint64(newHeadSlot-forkSlot)),
 				OldHeadBlock:        oldHeadRoot[:],
 				NewHeadBlock:        newHeadRoot[:],
-				OldHeadState:        oldStateRoot,
-				NewHeadState:        newStateRoot,
+				OldHeadState:        oldStateRoot[:],
+				NewHeadState:        newStateRoot[:],
 				Epoch:               slots.ToEpoch(newHeadSlot),
 				ExecutionOptimistic: isOptimistic,
 			},
@@ -141,7 +158,7 @@ func (s *Service) saveHead(ctx context.Context, newHeadRoot [32]byte, headBlock
 	// Forward an event capturing a new chain head over a common event feed
 	// done in a goroutine to avoid blocking the critical runtime main routine.
 	go func() {
-		if err := s.notifyNewHeadEvent(ctx, newHeadSlot, headState, newStateRoot, newHeadRoot[:]); err != nil {
+		if err := s.notifyNewHeadEvent(ctx, newHeadSlot, headState, newStateRoot[:], newHeadRoot[:]); err != nil {
 			log.WithError(err).Error("Could not notify event feed of new chain head")
 		}
 	}()
@@ -333,7 +350,7 @@ func (s *Service) notifyNewHeadEvent(
 // This saves the attestations between `orphanedRoot` and the common ancestor root that is derived using `newHeadRoot`.
 // It also filters out the attestations that is one epoch older as a defense so invalid attestations don't flow into the attestation pool.
 func (s *Service) saveOrphanedAtts(ctx context.Context, orphanedRoot [32]byte, newHeadRoot [32]byte) error {
-	commonAncestorRoot, err := s.ForkChoicer().CommonAncestorRoot(ctx, newHeadRoot, orphanedRoot)
+	commonAncestorRoot, _, err := s.ForkChoicer().CommonAncestor(ctx, newHeadRoot, orphanedRoot)
 	switch {
 	// Exit early if there's no common ancestor and root doesn't exist, there would be nothing to save.
 	case errors.Is(err, forkchoice.ErrUnknownCommonAncestor):
@@ -371,7 +388,8 @@ func (s *Service) saveOrphanedAtts(ctx context.Context, orphanedRoot [32]byte, n
 			}
 			saveOrphanedAttCount.Inc()
 		}
-		orphanedRoot = bytesutil.ToBytes32(orphanedBlk.Block().ParentRoot())
+		parentRoot := orphanedBlk.Block().ParentRoot()
+		orphanedRoot = bytesutil.ToBytes32(parentRoot[:])
 	}
 	return nil
 }
--- a/beacon-chain/blockchain/head_sync_committee_info_test.go
+++ b/beacon-chain/blockchain/head_sync_committee_info_test.go
@@ -7,6 +7,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/cache"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
 	dbtest "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
@@ -19,7 +20,7 @@ func TestService_headSyncCommitteeFetcher_Errors(t *testing.T) {
 	beaconDB := dbtest.SetupDB(t)
 	c := &Service{
 		cfg: &config{
-			StateGen: stategen.New(beaconDB),
+			StateGen: stategen.New(beaconDB, doublylinkedtree.New()),
 		},
 	}
 	c.head = &head{}
@@ -37,7 +38,7 @@ func TestService_HeadDomainFetcher_Errors(t *testing.T) {
 	beaconDB := dbtest.SetupDB(t)
 	c := &Service{
 		cfg: &config{
-			StateGen: stategen.New(beaconDB),
+			StateGen: stategen.New(beaconDB, doublylinkedtree.New()),
 		},
 	}
 	c.head = &head{}
--- a/beacon-chain/blockchain/head_test.go
+++ b/beacon-chain/blockchain/head_test.go
@@ -10,7 +10,6 @@ import (
 	mock "github.com/prysmaticlabs/prysm/v3/beacon-chain/blockchain/testing"
 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/v3/config/features"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
@@ -50,7 +49,7 @@ func TestSaveHead_Different(t *testing.T) {
 	require.NoError(t, err)
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	state, blkRoot, err := prepareForkchoiceState(ctx, oldBlock.Block().Slot(), oldRoot, bytesutil.ToBytes32(oldBlock.Block().ParentRoot()), [32]byte{}, ojc, ofc)
+	state, blkRoot, err := prepareForkchoiceState(ctx, oldBlock.Block().Slot(), oldRoot, oldBlock.Block().ParentRoot(), [32]byte{}, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
 	service.head = &head{
@@ -66,11 +65,11 @@ func TestSaveHead_Different(t *testing.T) {
 	wsb := util.SaveBlock(t, context.Background(), service.cfg.BeaconDB, newHeadSignedBlock)
 	newRoot, err := newHeadBlock.HashTreeRoot()
 	require.NoError(t, err)
-	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot()-1, bytesutil.ToBytes32(wsb.Block().ParentRoot()), service.cfg.ForkChoiceStore.CachedHeadRoot(), [32]byte{}, ojc, ofc)
+	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot()-1, wsb.Block().ParentRoot(), service.cfg.ForkChoiceStore.CachedHeadRoot(), [32]byte{}, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))

-	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot(), newRoot, bytesutil.ToBytes32(wsb.Block().ParentRoot()), [32]byte{}, ojc, ofc)
+	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot(), newRoot, wsb.Block().ParentRoot(), [32]byte{}, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
 	headState, err := util.NewBeaconState()
@@ -90,7 +89,7 @@ func TestSaveHead_Different(t *testing.T) {
 	pb, err := headBlock.Proto()
 	require.NoError(t, err)
 	assert.DeepEqual(t, newHeadSignedBlock, pb, "Head did not change")
-	assert.DeepSSZEqual(t, headState.CloneInnerState(), service.headState(ctx).CloneInnerState(), "Head did not change")
+	assert.DeepSSZEqual(t, headState.ToProto(), service.headState(ctx).ToProto(), "Head did not change")
 }

 func TestSaveHead_Different_Reorg(t *testing.T) {
@@ -104,7 +103,7 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	require.NoError(t, err)
 	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
 	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-	state, blkRoot, err := prepareForkchoiceState(ctx, oldBlock.Block().Slot(), oldRoot, bytesutil.ToBytes32(oldBlock.Block().ParentRoot()), [32]byte{}, ojc, ofc)
+	state, blkRoot, err := prepareForkchoiceState(ctx, oldBlock.Block().Slot(), oldRoot, oldBlock.Block().ParentRoot(), [32]byte{}, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
 	service.head = &head{
@@ -114,7 +113,7 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	}

 	reorgChainParent := [32]byte{'B'}
-	state, blkRoot, err = prepareForkchoiceState(ctx, 0, reorgChainParent, oldRoot, bytesutil.ToBytes32(oldBlock.Block().ParentRoot()), ojc, ofc)
+	state, blkRoot, err = prepareForkchoiceState(ctx, 0, reorgChainParent, oldRoot, oldBlock.Block().ParentRoot(), ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))

@@ -126,7 +125,7 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	wsb := util.SaveBlock(t, context.Background(), service.cfg.BeaconDB, newHeadSignedBlock)
 	newRoot, err := newHeadBlock.HashTreeRoot()
 	require.NoError(t, err)
-	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot(), newRoot, bytesutil.ToBytes32(wsb.Block().ParentRoot()), [32]byte{}, ojc, ofc)
+	state, blkRoot, err = prepareForkchoiceState(ctx, wsb.Block().Slot(), newRoot, wsb.Block().ParentRoot(), [32]byte{}, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
 	headState, err := util.NewBeaconState()
@@ -148,8 +147,10 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	pb, err := headBlock.Proto()
 	require.NoError(t, err)
 	assert.DeepEqual(t, newHeadSignedBlock, pb, "Head did not change")
-	assert.DeepSSZEqual(t, headState.CloneInnerState(), service.headState(ctx).CloneInnerState(), "Head did not change")
+	assert.DeepSSZEqual(t, headState.ToProto(), service.headState(ctx).ToProto(), "Head did not change")
 	require.LogsContain(t, hook, "Chain reorg occurred")
+	require.LogsContain(t, hook, "distance=1")
+	require.LogsContain(t, hook, "depth=1")
 }

 func TestCacheJustifiedStateBalances_CanCache(t *testing.T) {
@@ -232,64 +233,6 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 	})
 }

-func TestSaveOrphanedAtts_NoCommonAncestor_Protoarray(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-	service := setupBeaconChain(t, beaconDB)
-	// this test does not make sense in doubly linked tree since it enforces
-	// that the finalized node is a common ancestor
-	service.cfg.ForkChoiceStore = protoarray.New()
-
-	service.genesisTime = time.Now().Add(time.Duration(-10*int64(1)*int64(params.BeaconConfig().SecondsPerSlot)) * time.Second)
-
-	// Chain setup
-	// 0 -- 1 -- 2 -- 3
-	//    -4
-	st, keys := util.DeterministicGenesisState(t, 64)
-	blkG, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 0)
-	assert.NoError(t, err)
-	util.SaveBlock(t, ctx, service.cfg.BeaconDB, blkG)
-	rG, err := blkG.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	blk1, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 1)
-	assert.NoError(t, err)
-	blk1.Block.ParentRoot = rG[:]
-	r1, err := blk1.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	blk2, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 2)
-	assert.NoError(t, err)
-	blk2.Block.ParentRoot = r1[:]
-	r2, err := blk2.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	blk3, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 3)
-	assert.NoError(t, err)
-	blk3.Block.ParentRoot = r2[:]
-	r3, err := blk3.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	blk4 := util.NewBeaconBlock()
-	blk4.Block.Slot = 4
-	r4, err := blk4.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	for _, blk := range []*ethpb.SignedBeaconBlock{blkG, blk1, blk2, blk3, blk4} {
-		r, err := blk.Block.HashTreeRoot()
-		require.NoError(t, err)
-		ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-		ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
-		state, blkRoot, err := prepareForkchoiceState(ctx, blk.Block.Slot, r, bytesutil.ToBytes32(blk.Block.ParentRoot), [32]byte{}, ojc, ofc)
-		require.NoError(t, err)
-		require.NoError(t, service.ForkChoicer().InsertNode(ctx, state, blkRoot))
-		util.SaveBlock(t, ctx, beaconDB, blk)
-	}
-
-	require.NoError(t, service.saveOrphanedAtts(ctx, r3, r4))
-	require.Equal(t, 0, service.cfg.AttPool.AggregatedAttestationCount())
-}
-
 func TestSaveOrphanedAtts(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
@@ -536,7 +479,7 @@ func TestUpdateHead_noSavedChanges(t *testing.T) {
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}

--- a/beacon-chain/blockchain/log.go
+++ b/beacon-chain/blockchain/log.go
@@ -8,6 +8,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
+	consensusBlocks "github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -51,10 +52,15 @@ func logStateTransitionData(b interfaces.BeaconBlock) error {
 		}
 		log = log.WithField("payloadHash", fmt.Sprintf("%#x", bytesutil.Trunc(p.BlockHash())))
 		txs, err := p.Transactions()
-		if err != nil {
+		switch {
+		case errors.Is(err, consensusBlocks.ErrUnsupportedGetter):
+		case err != nil:
 			return err
+		default:
+			log = log.WithField("txCount", len(txs))
+			txsPerSlotCount.Set(float64(len(txs)))
 		}
-		log = log.WithField("txCount", len(txs))
+
 	}
 	log.Info("Finished applying state transition")
 	return nil
@@ -67,6 +73,7 @@ func logBlockSyncStatus(block interfaces.BeaconBlock, blockRoot [32]byte, justif
 	}
 	level := log.Logger.GetLevel()
 	if level >= logrus.DebugLevel {
+		parentRoot := block.ParentRoot()
 		log.WithFields(logrus.Fields{
 			"slot":                      block.Slot(),
 			"slotInEpoch":               block.Slot() % params.BeaconConfig().SlotsPerEpoch,
@@ -76,7 +83,7 @@ func logBlockSyncStatus(block interfaces.BeaconBlock, blockRoot [32]byte, justif
 			"justifiedRoot":             fmt.Sprintf("0x%s...", hex.EncodeToString(justified.Root)[:8]),
 			"finalizedEpoch":            finalized.Epoch,
 			"finalizedRoot":             fmt.Sprintf("0x%s...", hex.EncodeToString(finalized.Root)[:8]),
-			"parentRoot":                fmt.Sprintf("0x%s...", hex.EncodeToString(block.ParentRoot())[:8]),
+			"parentRoot":                fmt.Sprintf("0x%s...", hex.EncodeToString(parentRoot[:])[:8]),
 			"version":                   version.String(block.Version()),
 			"sinceSlotStartTime":        prysmTime.Now().Sub(startTime),
 			"chainServiceProcessedTime": prysmTime.Now().Sub(receivedTime),
@@ -110,12 +117,24 @@ func logPayload(block interfaces.BeaconBlock) error {
 		return errors.New("gas limit should not be 0")
 	}
 	gasUtilized := float64(payload.GasUsed()) / float64(payload.GasLimit())
-
-	log.WithFields(logrus.Fields{
+	fields := logrus.Fields{
 		"blockHash":   fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash())),
 		"parentHash":  fmt.Sprintf("%#x", bytesutil.Trunc(payload.ParentHash())),
 		"blockNumber": payload.BlockNumber,
 		"gasUtilized": fmt.Sprintf("%.2f", gasUtilized),
-	}).Debug("Synced new payload")
+	}
+	if block.Version() >= version.Capella {
+		withdrawals, err := payload.Withdrawals()
+		if err != nil {
+			return errors.Wrap(err, "could not get withdrawals")
+		}
+		fields["withdrawals"] = len(withdrawals)
+		changes, err := block.Body().BLSToExecutionChanges()
+		if err != nil {
+			return errors.Wrap(err, "could not get BLSToExecutionChanges")
+		}
+		fields["blsToExecutionChanges"] = len(changes)
+	}
+	log.WithFields(fields).Debug("Synced new payload")
 	return nil
 }
--- a/beacon-chain/blockchain/metrics.go
+++ b/beacon-chain/blockchain/metrics.go
@@ -158,10 +158,61 @@ var (
 		Name: "forkchoice_updated_optimistic_node_count",
 		Help: "Count the number of optimistic nodes after forkchoiceUpdated EE call",
 	})
+	forkchoiceUpdatedInvalidNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "forkchoice_updated_invalid_node_count",
+		Help: "Count the number of invalid nodes after forkchoiceUpdated EE call",
+	})
+	txsPerSlotCount = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "txs_per_slot_count",
+		Help: "Count the number of txs per slot",
+	})
 	missedPayloadIDFilledCount = promauto.NewCounter(prometheus.CounterOpts{
 		Name: "missed_payload_id_filled_count",
 		Help: "",
 	})
+	onBlockProcessingTime = promauto.NewSummary(prometheus.SummaryOpts{
+		Name: "on_block_processing_milliseconds",
+		Help: "Total time in milliseconds to complete a call to onBlock()",
+	})
+	stateTransitionProcessingTime = promauto.NewSummary(prometheus.SummaryOpts{
+		Name: "state_transition_processing_milliseconds",
+		Help: "Total time to call a state transition in onBlock()",
+	})
+	processAttsElapsedTime = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "process_attestations_milliseconds",
+			Help:    "Captures latency for process attestations (forkchoice) in milliseconds",
+			Buckets: []float64{1, 5, 20, 100, 500, 1000},
+		},
+	)
+	newAttHeadElapsedTime = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "new_att_head_milliseconds",
+			Help:    "Captures latency for new attestation head in milliseconds",
+			Buckets: []float64{1, 5, 20, 100, 500, 1000},
+		},
+	)
+	newBlockHeadElapsedTime = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "new_block_head_milliseconds",
+			Help:    "Captures latency for new block head in milliseconds",
+			Buckets: []float64{1, 5, 20, 100, 500, 1000},
+		},
+	)
+	reorgDistance = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "reorg_distance",
+			Help:    "Captures distance of reorgs. Distance is defined as the number of blocks between the old head and the new head",
+			Buckets: []float64{1, 2, 4, 8, 16, 32, 64},
+		},
+	)
+	reorgDepth = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "reorg_depth",
+			Help:    "Captures depth of reorgs. Depth is defined as the number of blocks between the head and the common ancestor",
+			Buckets: []float64{1, 2, 4, 8, 16, 32},
+		},
+	)
 )

 // reportSlotMetrics reports slot related metrics.
@@ -277,7 +328,7 @@ func reportEpochMetrics(ctx context.Context, postState, headState state.BeaconSt
 		if err != nil {
 			return err
 		}
-	case version.Altair, version.Bellatrix:
+	case version.Altair, version.Bellatrix, version.Capella:
 		v, b, err = altair.InitializePrecomputeValidators(ctx, headState)
 		if err != nil {
 			return err
@@ -287,7 +338,7 @@ func reportEpochMetrics(ctx context.Context, postState, headState state.BeaconSt
 			return err
 		}
 	default:
-		return errors.Errorf("invalid state type provided: %T", headState.InnerStateUnsafe())
+		return errors.Errorf("invalid state type provided: %T", headState.ToProtoUnsafe())
 	}
 	prevEpochActiveBalances.Set(float64(b.ActivePrevEpoch))
 	prevEpochSourceBalances.Set(float64(b.PrevEpochAttested))
--- a/beacon-chain/blockchain/mock_test.go
+++ b/beacon-chain/blockchain/mock_test.go
@@ -6,17 +6,17 @@ import (
 	"testing"

 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 )

 func testServiceOptsWithDB(t *testing.T) []Option {
 	beaconDB := testDB.SetupDB(t)
-	fcs := protoarray.New()
+	fcs := doublylinkedtree.New()
 	return []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 }
--- a/beacon-chain/blockchain/options.go
+++ b/beacon-chain/blockchain/options.go
@@ -9,6 +9,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/execution"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/attestations"
+	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/blstoexec"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/slashings"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/voluntaryexits"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/p2p"
@@ -99,6 +100,14 @@ func WithSlashingPool(p slashings.PoolManager) Option {
 	}
 }

+// WithBLSToExecPool to keep track of BLS to Execution address changes.
+func WithBLSToExecPool(p blstoexec.PoolManager) Option {
+	return func(s *Service) error {
+		s.cfg.BLSToExecPool = p
+		return nil
+	}
+}
+
 // WithP2PBroadcaster to broadcast messages after appropriate processing.
 func WithP2PBroadcaster(p p2p.Broadcaster) Option {
 	return func(s *Service) error {
--- a/beacon-chain/blockchain/pow_block.go
+++ b/beacon-chain/blockchain/pow_block.go
@@ -22,20 +22,21 @@ import (
 // validateMergeBlock validates terminal block hash in the event of manual overrides before checking for total difficulty.
 //
 // def validate_merge_block(block: BeaconBlock) -> None:
-//    if TERMINAL_BLOCK_HASH != Hash32():
-//        # If `TERMINAL_BLOCK_HASH` is used as an override, the activation epoch must be reached.
-//        assert compute_epoch_at_slot(block.slot) >= TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH
-//        assert block.body.execution_payload.parent_hash == TERMINAL_BLOCK_HASH
-//        return
 //
-//    pow_block = get_pow_block(block.body.execution_payload.parent_hash)
-//    # Check if `pow_block` is available
-//    assert pow_block is not None
-//    pow_parent = get_pow_block(pow_block.parent_hash)
-//    # Check if `pow_parent` is available
-//    assert pow_parent is not None
-//    # Check if `pow_block` is a valid terminal PoW block
-//    assert is_valid_terminal_pow_block(pow_block, pow_parent)
+//	if TERMINAL_BLOCK_HASH != Hash32():
+//	    # If `TERMINAL_BLOCK_HASH` is used as an override, the activation epoch must be reached.
+//	    assert compute_epoch_at_slot(block.slot) >= TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH
+//	    assert block.body.execution_payload.parent_hash == TERMINAL_BLOCK_HASH
+//	    return
+//
+//	pow_block = get_pow_block(block.body.execution_payload.parent_hash)
+//	# Check if `pow_block` is available
+//	assert pow_block is not None
+//	pow_parent = get_pow_block(pow_block.parent_hash)
+//	# Check if `pow_parent` is available
+//	assert pow_parent is not None
+//	# Check if `pow_block` is a valid terminal PoW block
+//	assert is_valid_terminal_pow_block(pow_block, pow_parent)
 func (s *Service) validateMergeBlock(ctx context.Context, b interfaces.SignedBeaconBlock) error {
 	if err := blocks.BeaconBlockIsNil(b); err != nil {
 		return err
@@ -105,10 +106,11 @@ func (s *Service) getBlkParentHashAndTD(ctx context.Context, blkHash []byte) ([]
 // validateTerminalBlockHash validates if the merge block is a valid terminal PoW block.
 // spec code:
 // if TERMINAL_BLOCK_HASH != Hash32():
-//        # If `TERMINAL_BLOCK_HASH` is used as an override, the activation epoch must be reached.
-//        assert compute_epoch_at_slot(block.slot) >= TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH
-//        assert block.body.execution_payload.parent_hash == TERMINAL_BLOCK_HASH
-//        return
+//
+//	# If `TERMINAL_BLOCK_HASH` is used as an override, the activation epoch must be reached.
+//	assert compute_epoch_at_slot(block.slot) >= TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH
+//	assert block.body.execution_payload.parent_hash == TERMINAL_BLOCK_HASH
+//	return
 func validateTerminalBlockHash(blkSlot types.Slot, payload interfaces.ExecutionData) error {
 	if bytesutil.ToBytes32(params.BeaconConfig().TerminalBlockHash.Bytes()) == [32]byte{} {
 		return nil
@@ -125,9 +127,10 @@ func validateTerminalBlockHash(blkSlot types.Slot, payload interfaces.ExecutionD
 // validateTerminalBlockDifficulties validates terminal pow block by comparing own total difficulty with parent's total difficulty.
 //
 // def is_valid_terminal_pow_block(block: PowBlock, parent: PowBlock) -> bool:
-//    is_total_difficulty_reached = block.total_difficulty >= TERMINAL_TOTAL_DIFFICULTY
-//    is_parent_total_difficulty_valid = parent.total_difficulty < TERMINAL_TOTAL_DIFFICULTY
-//    return is_total_difficulty_reached and is_parent_total_difficulty_valid
+//
+//	is_total_difficulty_reached = block.total_difficulty >= TERMINAL_TOTAL_DIFFICULTY
+//	is_parent_total_difficulty_valid = parent.total_difficulty < TERMINAL_TOTAL_DIFFICULTY
+//	return is_total_difficulty_reached and is_parent_total_difficulty_valid
 func validateTerminalBlockDifficulties(currentDifficulty *uint256.Int, parentDifficulty *uint256.Int) (bool, error) {
 	b, ok := new(big.Int).SetString(params.BeaconConfig().TerminalTotalDifficulty, 10)
 	if !ok {
--- a/beacon-chain/blockchain/pow_block_test.go
+++ b/beacon-chain/blockchain/pow_block_test.go
@@ -10,7 +10,7 @@ import (
 	"github.com/holiman/uint256"
 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
 	mocks "github.com/prysmaticlabs/prysm/v3/beacon-chain/execution/testing"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
@@ -109,10 +109,10 @@ func Test_validateMergeBlock(t *testing.T) {

 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
-	fcs := protoarray.New()
+	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	service, err := NewService(ctx, opts...)
@@ -159,10 +159,10 @@ func Test_validateMergeBlock(t *testing.T) {
 func Test_getBlkParentHashAndTD(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
-	fcs := protoarray.New()
+	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	service, err := NewService(ctx, opts...)
--- a/beacon-chain/blockchain/process_attestation.go
+++ b/beacon-chain/blockchain/process_attestation.go
@@ -19,23 +19,24 @@ import (
 // The delay is handled by the caller in `processAttestations`.
 //
 // Spec pseudocode definition:
-//   def on_attestation(store: Store, attestation: Attestation) -> None:
-//    """
-//    Run ``on_attestation`` upon receiving a new ``attestation`` from either within a block or directly on the wire.
 //
-//    An ``attestation`` that is asserted as invalid may be valid at a later time,
-//    consider scheduling it for later processing in such case.
-//    """
-//    validate_on_attestation(store, attestation)
-//    store_target_checkpoint_state(store, attestation.data.target)
+//	def on_attestation(store: Store, attestation: Attestation) -> None:
+//	 """
+//	 Run ``on_attestation`` upon receiving a new ``attestation`` from either within a block or directly on the wire.
 //
-//    # Get state at the `target` to fully validate attestation
-//    target_state = store.checkpoint_states[attestation.data.target]
-//    indexed_attestation = get_indexed_attestation(target_state, attestation)
-//    assert is_valid_indexed_attestation(target_state, indexed_attestation)
+//	 An ``attestation`` that is asserted as invalid may be valid at a later time,
+//	 consider scheduling it for later processing in such case.
+//	 """
+//	 validate_on_attestation(store, attestation)
+//	 store_target_checkpoint_state(store, attestation.data.target)
 //
-//    # Update latest messages for attesting indices
-//    update_latest_messages(store, indexed_attestation.attesting_indices, attestation)
+//	 # Get state at the `target` to fully validate attestation
+//	 target_state = store.checkpoint_states[attestation.data.target]
+//	 indexed_attestation = get_indexed_attestation(target_state, attestation)
+//	 assert is_valid_indexed_attestation(target_state, indexed_attestation)
+//
+//	 # Update latest messages for attesting indices
+//	 update_latest_messages(store, indexed_attestation.attesting_indices, attestation)
 func (s *Service) OnAttestation(ctx context.Context, a *ethpb.Attestation) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.onAttestation")
 	defer span.End()
--- a/beacon-chain/blockchain/process_attestation_test.go
+++ b/beacon-chain/blockchain/process_attestation_test.go
@@ -8,7 +8,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/transition"
 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
@@ -22,14 +21,15 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/time/slots"
 )

-func TestStore_OnAttestation_ErrorConditions_ProtoArray(t *testing.T) {
+func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)

+	fc := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithForkChoiceStore(doublylinkedtree.New()),
-		WithStateGen(stategen.New(beaconDB)),
+		WithForkChoiceStore(fc),
+		WithStateGen(stategen.New(beaconDB, fc)),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -128,142 +128,6 @@ func TestStore_OnAttestation_ErrorConditions_ProtoArray(t *testing.T) {
 	}
 }

-func TestStore_OnAttestation_ErrorConditions_DoublyLinkedTree(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithForkChoiceStore(doublylinkedtree.New()),
-		WithStateGen(stategen.New(beaconDB)),
-	}
-	service, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-
-	_, err = blockTree1(t, beaconDB, []byte{'g'})
-	require.NoError(t, err)
-
-	blkWithoutState := util.NewBeaconBlock()
-	blkWithoutState.Block.Slot = 0
-	util.SaveBlock(t, ctx, beaconDB, blkWithoutState)
-	BlkWithOutStateRoot, err := blkWithoutState.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	blkWithStateBadAtt := util.NewBeaconBlock()
-	blkWithStateBadAtt.Block.Slot = 1
-	util.SaveBlock(t, ctx, beaconDB, blkWithStateBadAtt)
-	BlkWithStateBadAttRoot, err := blkWithStateBadAtt.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	s, err := util.NewBeaconState()
-	require.NoError(t, err)
-	require.NoError(t, s.SetSlot(100*params.BeaconConfig().SlotsPerEpoch))
-	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, s, BlkWithStateBadAttRoot))
-
-	blkWithValidState := util.NewBeaconBlock()
-	blkWithValidState.Block.Slot = 2
-	util.SaveBlock(t, ctx, beaconDB, blkWithValidState)
-
-	blkWithValidStateRoot, err := blkWithValidState.Block.HashTreeRoot()
-	require.NoError(t, err)
-	s, err = util.NewBeaconState()
-	require.NoError(t, err)
-	err = s.SetFork(&ethpb.Fork{
-		Epoch:           0,
-		CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
-		PreviousVersion: params.BeaconConfig().GenesisForkVersion,
-	})
-	require.NoError(t, err)
-	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, s, blkWithValidStateRoot))
-
-	tests := []struct {
-		name      string
-		a         *ethpb.Attestation
-		wantedErr string
-	}{
-		{
-			name:      "attestation's data slot not aligned with target vote",
-			a:         util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: params.BeaconConfig().SlotsPerEpoch, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}}}),
-			wantedErr: "slot 32 does not match target epoch 0",
-		},
-		{
-			name:      "no pre state for attestations's target block",
-			a:         util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Target: &ethpb.Checkpoint{Root: BlkWithOutStateRoot[:]}}}),
-			wantedErr: "could not get pre state for epoch 0",
-		},
-		{
-			name: "process attestation doesn't match current epoch",
-			a: util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 100 * params.BeaconConfig().SlotsPerEpoch, Target: &ethpb.Checkpoint{Epoch: 100,
-				Root: BlkWithStateBadAttRoot[:]}}}),
-			wantedErr: "target epoch 100 does not match current epoch",
-		},
-		{
-			name:      "process nil attestation",
-			a:         nil,
-			wantedErr: "attestation can't be nil",
-		},
-		{
-			name:      "process nil field (a.Data) in attestation",
-			a:         &ethpb.Attestation{},
-			wantedErr: "attestation's data can't be nil",
-		},
-		{
-			name: "process nil field (a.Target) in attestation",
-			a: &ethpb.Attestation{
-				Data: &ethpb.AttestationData{
-					BeaconBlockRoot: make([]byte, fieldparams.RootLength),
-					Target:          nil,
-					Source:          &ethpb.Checkpoint{Root: make([]byte, fieldparams.RootLength)},
-				},
-				AggregationBits: make([]byte, 1),
-				Signature:       make([]byte, 96),
-			},
-			wantedErr: "attestation's target can't be nil",
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			err := service.OnAttestation(ctx, tt.a)
-			if tt.wantedErr != "" {
-				assert.ErrorContains(t, tt.wantedErr, err)
-			} else {
-				assert.NoError(t, err)
-			}
-		})
-	}
-}
-
-func TestStore_OnAttestation_Ok_ProtoArray(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	fcs := protoarray.New()
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(fcs),
-	}
-	service, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-	genesisState, pks := util.DeterministicGenesisState(t, 64)
-	service.SetGenesisTime(time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0))
-	require.NoError(t, service.saveGenesisData(ctx, genesisState))
-	att, err := util.GenerateAttestations(genesisState, pks, 1, 0, false)
-	require.NoError(t, err)
-	tRoot := bytesutil.ToBytes32(att[0].Data.Target.Root)
-	copied := genesisState.Copy()
-	copied, err = transition.ProcessSlots(ctx, copied, 1)
-	require.NoError(t, err)
-	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
-	ojc := &ethpb.Checkpoint{Epoch: 1, Root: tRoot[:]}
-	ofc := &ethpb.Checkpoint{Epoch: 1, Root: tRoot[:]}
-	state, blkRoot, 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.OnAttestation(ctx, att[0]))
-}
-
 func TestStore_OnAttestation_Ok_DoublyLinkedTree(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
@@ -271,7 +135,7 @@ func TestStore_OnAttestation_Ok_DoublyLinkedTree(t *testing.T) {
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	service, err := NewService(ctx, opts...)
@@ -300,7 +164,7 @@ func TestStore_SaveCheckpointState(t *testing.T) {

 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, doublylinkedtree.New())),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -362,7 +226,7 @@ func TestStore_UpdateCheckpointState(t *testing.T) {

 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, doublylinkedtree.New())),
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
@@ -392,7 +256,7 @@ func TestStore_UpdateCheckpointState(t *testing.T) {

 	cached, err = service.checkpointStateCache.StateByCheckpoint(newCheckpoint)
 	require.NoError(t, err)
-	require.DeepSSZEqual(t, returned.InnerStateUnsafe(), cached.InnerStateUnsafe())
+	require.DeepSSZEqual(t, returned.ToProtoUnsafe(), cached.ToProtoUnsafe())
 }

 func TestAttEpoch_MatchPrevEpoch(t *testing.T) {
@@ -461,37 +325,6 @@ func TestVerifyBeaconBlock_OK(t *testing.T) {
 	assert.NoError(t, service.verifyBeaconBlock(ctx, d), "Did not receive the wanted error")
 }

-func TestVerifyFinalizedConsistency_InconsistentRoot_ProtoArray(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	fcs := protoarray.New()
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(fcs),
-	}
-	service, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-
-	b32 := util.NewBeaconBlock()
-	b32.Block.Slot = 32
-	util.SaveBlock(t, ctx, service.cfg.BeaconDB, b32)
-	r32, err := b32.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	require.NoError(t, service.ForkChoicer().UpdateFinalizedCheckpoint(&forkchoicetypes.Checkpoint{Epoch: 1}))
-	b33 := util.NewBeaconBlock()
-	b33.Block.Slot = 33
-	b33.Block.ParentRoot = r32[:]
-	util.SaveBlock(t, ctx, service.cfg.BeaconDB, b33)
-	r33, err := b33.Block.HashTreeRoot()
-	require.NoError(t, err)
-
-	err = service.VerifyFinalizedConsistency(context.Background(), r33[:])
-	require.ErrorContains(t, "Root and finalized store are not consistent", err)
-}
-
 func TestVerifyFinalizedConsistency_InconsistentRoot_DoublyLinkedTree(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
@@ -499,7 +332,7 @@ func TestVerifyFinalizedConsistency_InconsistentRoot_DoublyLinkedTree(t *testing
 	fcs := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fcs)),
 		WithForkChoiceStore(fcs),
 	}
 	service, err := NewService(ctx, opts...)
--- a/beacon-chain/blockchain/process_block.go
+++ b/beacon-chain/blockchain/process_block.go
@@ -23,7 +23,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v3/monitoring/tracing"
-	enginev1 "github.com/prysmaticlabs/prysm/v3/proto/engine/v1"
 	ethpbv1 "github.com/prysmaticlabs/prysm/v3/proto/eth/v1"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1/attestation"
@@ -46,58 +45,60 @@ var initialSyncBlockCacheSize = uint64(2 * params.BeaconConfig().SlotsPerEpoch)
 // computation in this method and methods it calls into.
 //
 // Spec pseudocode definition:
-//   def on_block(store: Store, signed_block: SignedBeaconBlock) -> None:
-//    block = signed_block.message
-//    # Parent block must be known
-//    assert block.parent_root in store.block_states
-//    # Make a copy of the state to avoid mutability issues
-//    pre_state = copy(store.block_states[block.parent_root])
-//    # Blocks cannot be in the future. If they are, their consideration must be delayed until the are in the past.
-//    assert get_current_slot(store) >= block.slot
 //
-//    # Check that block is later than the finalized epoch slot (optimization to reduce calls to get_ancestor)
-//    finalized_slot = compute_start_slot_at_epoch(store.finalized_checkpoint.epoch)
-//    assert block.slot > finalized_slot
-//    # Check block is a descendant of the finalized block at the checkpoint finalized slot
-//    assert get_ancestor(store, block.parent_root, finalized_slot) == store.finalized_checkpoint.root
+//	def on_block(store: Store, signed_block: SignedBeaconBlock) -> None:
+//	 block = signed_block.message
+//	 # Parent block must be known
+//	 assert block.parent_root in store.block_states
+//	 # Make a copy of the state to avoid mutability issues
+//	 pre_state = copy(store.block_states[block.parent_root])
+//	 # Blocks cannot be in the future. If they are, their consideration must be delayed until the are in the past.
+//	 assert get_current_slot(store) >= block.slot
 //
-//    # Check the block is valid and compute the post-state
-//    state = pre_state.copy()
-//    state_transition(state, signed_block, True)
-//    # Add new block to the store
-//    store.blocks[hash_tree_root(block)] = block
-//    # Add new state for this block to the store
-//    store.block_states[hash_tree_root(block)] = state
+//	 # Check that block is later than the finalized epoch slot (optimization to reduce calls to get_ancestor)
+//	 finalized_slot = compute_start_slot_at_epoch(store.finalized_checkpoint.epoch)
+//	 assert block.slot > finalized_slot
+//	 # Check block is a descendant of the finalized block at the checkpoint finalized slot
+//	 assert get_ancestor(store, block.parent_root, finalized_slot) == store.finalized_checkpoint.root
 //
-//    # Update justified checkpoint
-//    if state.current_justified_checkpoint.epoch > store.justified_checkpoint.epoch:
-//        if state.current_justified_checkpoint.epoch > store.best_justified_checkpoint.epoch:
-//            store.best_justified_checkpoint = state.current_justified_checkpoint
-//        if should_update_justified_checkpoint(store, state.current_justified_checkpoint):
-//            store.justified_checkpoint = state.current_justified_checkpoint
+//	 # Check the block is valid and compute the post-state
+//	 state = pre_state.copy()
+//	 state_transition(state, signed_block, True)
+//	 # Add new block to the store
+//	 store.blocks[hash_tree_root(block)] = block
+//	 # Add new state for this block to the store
+//	 store.block_states[hash_tree_root(block)] = state
 //
-//    # Update finalized checkpoint
-//    if state.finalized_checkpoint.epoch > store.finalized_checkpoint.epoch:
-//        store.finalized_checkpoint = state.finalized_checkpoint
+//	 # Update justified checkpoint
+//	 if state.current_justified_checkpoint.epoch > store.justified_checkpoint.epoch:
+//	     if state.current_justified_checkpoint.epoch > store.best_justified_checkpoint.epoch:
+//	         store.best_justified_checkpoint = state.current_justified_checkpoint
+//	     if should_update_justified_checkpoint(store, state.current_justified_checkpoint):
+//	         store.justified_checkpoint = state.current_justified_checkpoint
 //
-//        # Potentially update justified if different from store
-//        if store.justified_checkpoint != state.current_justified_checkpoint:
-//            # Update justified if new justified is later than store justified
-//            if state.current_justified_checkpoint.epoch > store.justified_checkpoint.epoch:
-//                store.justified_checkpoint = state.current_justified_checkpoint
-//                return
+//	 # Update finalized checkpoint
+//	 if state.finalized_checkpoint.epoch > store.finalized_checkpoint.epoch:
+//	     store.finalized_checkpoint = state.finalized_checkpoint
 //
-//            # Update justified if store justified is not in chain with finalized checkpoint
-//            finalized_slot = compute_start_slot_at_epoch(store.finalized_checkpoint.epoch)
-//            ancestor_at_finalized_slot = get_ancestor(store, store.justified_checkpoint.root, finalized_slot)
-//            if ancestor_at_finalized_slot != store.finalized_checkpoint.root:
-//                store.justified_checkpoint = state.current_justified_checkpoint
+//	     # Potentially update justified if different from store
+//	     if store.justified_checkpoint != state.current_justified_checkpoint:
+//	         # Update justified if new justified is later than store justified
+//	         if state.current_justified_checkpoint.epoch > store.justified_checkpoint.epoch:
+//	             store.justified_checkpoint = state.current_justified_checkpoint
+//	             return
+//
+//	         # Update justified if store justified is not in chain with finalized checkpoint
+//	         finalized_slot = compute_start_slot_at_epoch(store.finalized_checkpoint.epoch)
+//	         ancestor_at_finalized_slot = get_ancestor(store, store.justified_checkpoint.root, finalized_slot)
+//	         if ancestor_at_finalized_slot != store.finalized_checkpoint.root:
+//	             store.justified_checkpoint = state.current_justified_checkpoint
 func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlock, blockRoot [32]byte) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.onBlock")
 	defer span.End()
 	if err := consensusblocks.BeaconBlockIsNil(signed); err != nil {
 		return invalidBlock{error: err}
 	}
+	startTime := time.Now()
 	b := signed.Block()

 	preState, err := s.getBlockPreState(ctx, b)
@@ -115,10 +116,13 @@ func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlo
 	if err != nil {
 		return err
 	}
+	stateTransitionStartTime := time.Now()
 	postState, err := transition.ExecuteStateTransition(ctx, preState, signed)
 	if err != nil {
 		return invalidBlock{error: err}
 	}
+	stateTransitionProcessingTime.Observe(float64(time.Since(stateTransitionStartTime).Milliseconds()))
+
 	postStateVersion, postStateHeader, err := getStateVersionAndPayload(postState)
 	if err != nil {
 		return err
@@ -139,6 +143,13 @@ func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlo
 	if err := s.insertBlockToForkchoiceStore(ctx, signed.Block(), blockRoot, postState); err != nil {
 		return errors.Wrapf(err, "could not insert block %d to fork choice store", signed.Block().Slot())
 	}
+	if err := s.handleBlockAttestations(ctx, signed.Block(), postState); err != nil {
+		return errors.Wrap(err, "could not handle block's attestations")
+	}
+	if err := s.handleBlockBLSToExecChanges(signed.Block()); err != nil {
+		return errors.Wrap(err, "could not handle block's BLSToExecutionChanges")
+	}
+
 	s.InsertSlashingsToForkChoiceStore(ctx, signed.Block().Body().AttesterSlashings())
 	if isValidPayload {
 		if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, blockRoot); err != nil {
@@ -179,10 +190,14 @@ func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlo
 		msg := fmt.Sprintf("could not read balances for state w/ justified checkpoint %#x", justified.Root)
 		return errors.Wrap(err, msg)
 	}
+
+	start := time.Now()
 	headRoot, err := s.cfg.ForkChoiceStore.Head(ctx, balances)
 	if err != nil {
 		log.WithError(err).Warn("Could not update head")
 	}
+	newBlockHeadElapsedTime.Observe(float64(time.Since(start).Milliseconds()))
+
 	if err := s.notifyEngineIfChangedHead(ctx, headRoot); err != nil {
 		return err
 	}
@@ -237,12 +252,13 @@ func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlo
 		}
 		go func() {
 			// Send an event regarding the new finalized checkpoint over a common event feed.
+			stateRoot := signed.Block().StateRoot()
 			s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 				Type: statefeed.FinalizedCheckpoint,
 				Data: &ethpbv1.EventFinalizedCheckpoint{
 					Epoch:               postState.FinalizedCheckpoint().Epoch,
 					Block:               postState.FinalizedCheckpoint().Root,
-					State:               signed.Block().StateRoot(),
+					State:               stateRoot[:],
 					ExecutionOptimistic: isOptimistic,
 				},
 			})
@@ -259,14 +275,18 @@ func (s *Service) onBlock(ctx context.Context, signed interfaces.SignedBeaconBlo

 	}
 	defer reportAttestationInclusion(b)
-	return s.handleEpochBoundary(ctx, postState)
+	if err := s.handleEpochBoundary(ctx, postState); err != nil {
+		return err
+	}
+	onBlockProcessingTime.Observe(float64(time.Since(startTime).Milliseconds()))
+	return nil
 }

-func getStateVersionAndPayload(st state.BeaconState) (int, *enginev1.ExecutionPayloadHeader, error) {
+func getStateVersionAndPayload(st state.BeaconState) (int, interfaces.ExecutionData, error) {
 	if st == nil {
 		return 0, nil, errors.New("nil state")
 	}
-	var preStateHeader *enginev1.ExecutionPayloadHeader
+	var preStateHeader interfaces.ExecutionData
 	var err error
 	preStateVersion := st.Version()
 	switch preStateVersion {
@@ -302,7 +322,7 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []interfaces.SignedBeac
 	if err := s.verifyBlkPreState(ctx, b); err != nil {
 		return err
 	}
-	preState, err := s.cfg.StateGen.StateByRootInitialSync(ctx, bytesutil.ToBytes32(b.ParentRoot()))
+	preState, err := s.cfg.StateGen.StateByRootInitialSync(ctx, b.ParentRoot())
 	if err != nil {
 		return err
 	}
@@ -324,7 +344,7 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []interfaces.SignedBeac
 	}
 	type versionAndHeader struct {
 		version int
-		header  *enginev1.ExecutionPayloadHeader
+		header  interfaces.ExecutionData
 	}
 	preVersionAndHeaders := make([]*versionAndHeader, len(blks))
 	postVersionAndHeaders := make([]*versionAndHeader, len(blks))
@@ -501,7 +521,7 @@ func (s *Service) insertBlockToForkchoiceStore(ctx context.Context, blk interfac
 	ctx, span := trace.StartSpan(ctx, "blockChain.insertBlockToForkchoiceStore")
 	defer span.End()

-	if !s.cfg.ForkChoiceStore.HasNode(bytesutil.ToBytes32(blk.ParentRoot())) {
+	if !s.cfg.ForkChoiceStore.HasNode(blk.ParentRoot()) {
 		fCheckpoint := st.FinalizedCheckpoint()
 		jCheckpoint := st.CurrentJustifiedCheckpoint()
 		if err := s.fillInForkChoiceMissingBlocks(ctx, blk, fCheckpoint, jCheckpoint); err != nil {
@@ -516,6 +536,45 @@ func (s *Service) insertBlockToForkchoiceStore(ctx context.Context, blk interfac
 	return nil
 }

+// This feeds in the attestations included in the block to fork choice store. It's allows fork choice store
+// to gain information on the most current chain.
+func (s *Service) handleBlockAttestations(ctx context.Context, blk interfaces.BeaconBlock, st state.BeaconState) error {
+	// Feed in block's attestations to fork choice store.
+	for _, a := range blk.Body().Attestations() {
+		committee, err := helpers.BeaconCommitteeFromState(ctx, st, a.Data.Slot, a.Data.CommitteeIndex)
+		if err != nil {
+			return err
+		}
+		indices, err := attestation.AttestingIndices(a.AggregationBits, committee)
+		if err != nil {
+			return err
+		}
+		r := bytesutil.ToBytes32(a.Data.BeaconBlockRoot)
+		if s.cfg.ForkChoiceStore.HasNode(r) {
+			s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indices, r, a.Data.Target.Epoch)
+		} else if err := s.cfg.AttPool.SaveBlockAttestation(a); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *Service) handleBlockBLSToExecChanges(blk interfaces.BeaconBlock) error {
+	if blk.Version() < version.Capella {
+		return nil
+	}
+	changes, err := blk.Body().BLSToExecutionChanges()
+	if err != nil {
+		return errors.Wrap(err, "could not get BLSToExecutionChanges")
+	}
+	for _, change := range changes {
+		if err := s.cfg.BLSToExecPool.MarkIncluded(change); err != nil {
+			return errors.Wrap(err, "could not mark BLSToExecutionChange as included")
+		}
+	}
+	return nil
+}
+
 // InsertSlashingsToForkChoiceStore inserts attester slashing indices to fork choice store.
 // To call this function, it's caller's responsibility to ensure the slashing object is valid.
 func (s *Service) InsertSlashingsToForkChoiceStore(ctx context.Context, slashings []*ethpb.AttesterSlashing) {
@@ -568,7 +627,7 @@ func (s *Service) pruneCanonicalAttsFromPool(ctx context.Context, r [32]byte, b
 }

 // validateMergeTransitionBlock validates the merge transition block.
-func (s *Service) validateMergeTransitionBlock(ctx context.Context, stateVersion int, stateHeader *enginev1.ExecutionPayloadHeader, blk interfaces.SignedBeaconBlock) error {
+func (s *Service) validateMergeTransitionBlock(ctx context.Context, stateVersion int, stateHeader interfaces.ExecutionData, blk interfaces.SignedBeaconBlock) error {
 	// Skip validation if block is older than Bellatrix.
 	if blocks.IsPreBellatrixVersion(blk.Block().Version()) {
 		return nil
@@ -595,11 +654,7 @@ func (s *Service) validateMergeTransitionBlock(ctx context.Context, stateVersion

 	// Skip validation if the block is not a merge transition block.
 	// To reach here. The payload must be non-empty. If the state header is empty then it's at transition.
-	wh, err := consensusblocks.WrappedExecutionPayloadHeader(stateHeader)
-	if err != nil {
-		return err
-	}
-	empty, err := consensusblocks.IsEmptyExecutionData(wh)
+	empty, err := consensusblocks.IsEmptyExecutionData(stateHeader)
 	if err != nil {
 		return err
 	}
@@ -630,25 +685,8 @@ func (s *Service) fillMissingPayloadIDRoutine(ctx context.Context, stateFeed *ev
 		for {
 			select {
 			case ti := <-ticker.C:
-				if !atHalfSlot(ti) {
-					continue
-				}
-				_, id, has := s.cfg.ProposerSlotIndexCache.GetProposerPayloadIDs(s.CurrentSlot()+1, s.headRoot())
-				// There exists proposer for next slot, but we haven't called fcu w/ payload attribute yet.
-				if has && id == [8]byte{} {
-					headBlock, err := s.headBlock()
-					if err != nil {
-						log.WithError(err).Error("Could not get head block")
-					} else {
-						if _, err := s.notifyForkchoiceUpdate(ctx, &notifyForkchoiceUpdateArg{
-							headState: s.headState(ctx),
-							headRoot:  s.headRoot(),
-							headBlock: headBlock.Block(),
-						}); err != nil {
-							log.WithError(err).Error("Could not prepare payload on empty ID")
-						}
-					}
-					missedPayloadIDFilledCount.Inc()
+				if err := s.fillMissingBlockPayloadId(ctx, ti); err != nil {
+					log.WithError(err).Error("Could not fill missing payload ID")
 				}
 			case <-s.ctx.Done():
 				log.Debug("Context closed, exiting routine")
@@ -663,3 +701,31 @@ func atHalfSlot(t time.Time) bool {
 	s := params.BeaconConfig().SecondsPerSlot
 	return uint64(t.Second())%s == s/2
 }
+
+func (s *Service) fillMissingBlockPayloadId(ctx context.Context, ti time.Time) error {
+	if !atHalfSlot(ti) {
+		return nil
+	}
+	if s.CurrentSlot() == s.cfg.ForkChoiceStore.HighestReceivedBlockSlot() {
+		return nil
+	}
+	// Head root should be empty when retrieving proposer index for the next slot.
+	_, id, has := s.cfg.ProposerSlotIndexCache.GetProposerPayloadIDs(s.CurrentSlot()+1, [32]byte{} /* head root */)
+	// There exists proposer for next slot, but we haven't called fcu w/ payload attribute yet.
+	if has && id == [8]byte{} {
+		missedPayloadIDFilledCount.Inc()
+		headBlock, err := s.headBlock()
+		if err != nil {
+			return err
+		} else {
+			if _, err := s.notifyForkchoiceUpdate(ctx, &notifyForkchoiceUpdateArg{
+				headState: s.headState(ctx),
+				headRoot:  s.headRoot(),
+				headBlock: headBlock.Block(),
+			}); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
--- a/beacon-chain/blockchain/process_block_helpers.go
+++ b/beacon-chain/blockchain/process_block_helpers.go
@@ -8,7 +8,6 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
@@ -39,7 +38,7 @@ func (s *Service) getBlockPreState(ctx context.Context, b interfaces.BeaconBlock
 		return nil, err
 	}

-	preState, err := s.cfg.StateGen.StateByRoot(ctx, bytesutil.ToBytes32(b.ParentRoot()))
+	preState, err := s.cfg.StateGen.StateByRoot(ctx, b.ParentRoot())
 	if err != nil {
 		return nil, errors.Wrapf(err, "could not get pre state for slot %d", b.Slot())
 	}
@@ -65,7 +64,7 @@ func (s *Service) verifyBlkPreState(ctx context.Context, b interfaces.BeaconBloc
 	ctx, span := trace.StartSpan(ctx, "blockChain.verifyBlkPreState")
 	defer span.End()

-	parentRoot := bytesutil.ToBytes32(b.ParentRoot())
+	parentRoot := b.ParentRoot()
 	// Loosen the check to HasBlock because state summary gets saved in batches
 	// during initial syncing. There's no risk given a state summary object is just a
 	// a subset of the block object.
@@ -73,7 +72,7 @@ func (s *Service) verifyBlkPreState(ctx context.Context, b interfaces.BeaconBloc
 		return errors.New("could not reconstruct parent state")
 	}

-	if err := s.VerifyFinalizedBlkDescendant(ctx, bytesutil.ToBytes32(b.ParentRoot())); err != nil {
+	if err := s.VerifyFinalizedBlkDescendant(ctx, parentRoot); err != nil {
 		return err
 	}

@@ -135,11 +134,21 @@ func (s *Service) verifyBlkFinalizedSlot(b interfaces.BeaconBlock) error {
 }

 // updateFinalized saves the init sync blocks, finalized checkpoint, migrates
-// to cold old states and saves the last validated checkpoint to DB
+// to cold old states and saves the last validated checkpoint to DB. It returns
+// early if the new checkpoint is older than the one on db.
 func (s *Service) updateFinalized(ctx context.Context, cp *ethpb.Checkpoint) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.updateFinalized")
 	defer span.End()

+	// return early if new checkpoint is not newer than the one in DB
+	currentFinalized, err := s.cfg.BeaconDB.FinalizedCheckpoint(ctx)
+	if err != nil {
+		return err
+	}
+	if cp.Epoch <= currentFinalized.Epoch {
+		return nil
+	}
+
 	// Blocks need to be saved so that we can retrieve finalized block from
 	// DB when migrating states.
 	if err := s.cfg.BeaconDB.SaveBlocks(ctx, s.getInitSyncBlocks()); err != nil {
@@ -153,7 +162,7 @@ func (s *Service) updateFinalized(ctx context.Context, cp *ethpb.Checkpoint) err

 	fRoot := bytesutil.ToBytes32(cp.Root)
 	optimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(fRoot)
-	if err != nil && err != protoarray.ErrUnknownNodeRoot && err != doublylinkedtree.ErrNilNode {
+	if err != nil && !errors.Is(err, doublylinkedtree.ErrNilNode) {
 		return err
 	}
 	if !optimistic {
@@ -162,24 +171,30 @@ func (s *Service) updateFinalized(ctx context.Context, cp *ethpb.Checkpoint) err
 			return err
 		}
 	}
-	if err := s.cfg.StateGen.MigrateToCold(ctx, fRoot); err != nil {
-		return errors.Wrap(err, "could not migrate to cold")
-	}
+	go func() {
+		// We do not pass in the parent context from the method as this method call
+		// is meant to be asynchronous and run in the background rather than being
+		// tied to the execution of a block.
+		if err := s.cfg.StateGen.MigrateToCold(s.ctx, fRoot); err != nil {
+			log.WithError(err).Error("could not migrate to cold")
+		}
+	}()
 	return nil
 }

 // ancestor returns the block root of an ancestry block from the input block root.
 //
 // Spec pseudocode definition:
-//   def get_ancestor(store: Store, root: Root, slot: Slot) -> Root:
-//    block = store.blocks[root]
-//    if block.slot > slot:
-//        return get_ancestor(store, block.parent_root, slot)
-//    elif block.slot == slot:
-//        return root
-//    else:
-//        # root is older than queried slot, thus a skip slot. Return most recent root prior to slot
-//        return root
+//
+//	def get_ancestor(store: Store, root: Root, slot: Slot) -> Root:
+//	 block = store.blocks[root]
+//	 if block.slot > slot:
+//	     return get_ancestor(store, block.parent_root, slot)
+//	 elif block.slot == slot:
+//	     return root
+//	 else:
+//	     # root is older than queried slot, thus a skip slot. Return most recent root prior to slot
+//	     return root
 func (s *Service) ancestor(ctx context.Context, root []byte, slot types.Slot) ([]byte, error) {
 	ctx, span := trace.StartSpan(ctx, "blockChain.ancestor")
 	defer span.End()
@@ -231,7 +246,7 @@ func (s *Service) ancestorByDB(ctx context.Context, r [32]byte, slot types.Slot)
 		return r[:], nil
 	}

-	return s.ancestorByDB(ctx, bytesutil.ToBytes32(b.ParentRoot()), slot)
+	return s.ancestorByDB(ctx, b.ParentRoot(), slot)
 }

 // This retrieves missing blocks from DB (ie. the blocks that couldn't be received over sync) and inserts them to fork choice store.
@@ -249,7 +264,7 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfa
 	pendingNodes = append(pendingNodes, &forkchoicetypes.BlockAndCheckpoints{Block: blk,
 		JustifiedCheckpoint: jCheckpoint, FinalizedCheckpoint: fCheckpoint})
 	// As long as parent node is not in fork choice store, and parent node is in DB.
-	root := bytesutil.ToBytes32(blk.ParentRoot())
+	root := blk.ParentRoot()
 	for !s.cfg.ForkChoiceStore.HasNode(root) && s.cfg.BeaconDB.HasBlock(ctx, root) {
 		b, err := s.getBlock(ctx, root)
 		if err != nil {
@@ -258,7 +273,7 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfa
 		if b.Block().Slot() <= fSlot {
 			break
 		}
-		root = bytesutil.ToBytes32(b.Block().ParentRoot())
+		root = b.Block().ParentRoot()
 		args := &forkchoicetypes.BlockAndCheckpoints{Block: b.Block(),
 			JustifiedCheckpoint: jCheckpoint,
 			FinalizedCheckpoint: fCheckpoint}
@@ -267,7 +282,7 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk interfa
 	if len(pendingNodes) == 1 {
 		return nil
 	}
-	if root != s.ensureRootNotZeros(finalized.Root) {
+	if root != s.ensureRootNotZeros(finalized.Root) && !s.ForkChoicer().HasNode(root) {
 		return errNotDescendantOfFinalized
 	}
 	return s.cfg.ForkChoiceStore.InsertOptimisticChain(ctx, pendingNodes)
--- 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
@@ -122,12 +122,10 @@ func (s *Service) spawnProcessAttestationsRoutine(stateFeed *event.Feed) {
 			case <-st.C():
 				if err := s.ForkChoicer().NewSlot(s.ctx, s.CurrentSlot()); err != nil {
 					log.WithError(err).Error("Could not process new slot")
-					return
 				}

 				if err := s.UpdateHead(s.ctx); err != nil {
 					log.WithError(err).Error("Could not process attestations and update head")
-					return
 				}
 			}
 		}
@@ -137,27 +135,26 @@ func (s *Service) spawnProcessAttestationsRoutine(stateFeed *event.Feed) {
 // UpdateHead updates the canonical head of the chain based on information from fork-choice attestations and votes.
 // It requires no external inputs.
 func (s *Service) UpdateHead(ctx context.Context) error {
-	// Continue when there's no fork choice attestation, there's nothing to process and update head.
-	// This covers the condition when the node is still initial syncing to the head of the chain.
-	if s.cfg.AttPool.ForkchoiceAttestationCount() == 0 {
-		return nil
-	}
-
 	// Only one process can process attestations and update head at a time.
 	s.processAttestationsLock.Lock()
 	defer s.processAttestationsLock.Unlock()

+	start := time.Now()
 	s.processAttestations(ctx)
+	processAttsElapsedTime.Observe(float64(time.Since(start).Milliseconds()))

 	justified := s.ForkChoicer().JustifiedCheckpoint()
 	balances, err := s.justifiedBalances.get(ctx, justified.Root)
 	if err != nil {
 		return err
 	}
+	start = time.Now()
 	newHeadRoot, err := s.cfg.ForkChoiceStore.Head(ctx, balances)
 	if err != nil {
-		log.WithError(err).Warn("Resolving fork due to new attestation")
+		log.WithError(err).Error("Could not compute head from new attestations")
 	}
+	newAttHeadElapsedTime.Observe(float64(time.Since(start).Milliseconds()))
+
 	s.headLock.RLock()
 	if s.headRoot() != newHeadRoot {
 		log.WithFields(logrus.Fields{
--- a/beacon-chain/blockchain/receive_attestation_test.go
+++ b/beacon-chain/blockchain/receive_attestation_test.go
@@ -226,11 +226,11 @@ func TestService_ProcessAttestationsAndUpdateHead(t *testing.T) {
 	require.Equal(t, 2, fcs.NodeCount())
 	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))

-	// Generate attestatios for this block in Slot 1
+	// Generate attestations for this block in Slot 1
 	atts, err := util.GenerateAttestations(copied, pks, 1, 1, false)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(atts))
-	// Verify the target is in forchoice
+	// Verify the target is in forkchoice
 	require.Equal(t, true, fcs.HasNode(bytesutil.ToBytes32(atts[0].Data.BeaconBlockRoot)))

 	// Insert a new block to forkchoice
@@ -253,3 +253,52 @@ func TestService_ProcessAttestationsAndUpdateHead(t *testing.T) {
 	require.Equal(t, 0, len(service.cfg.AttPool.ForkchoiceAttestations())) // Validate att pool is empty
 	require.Equal(t, tRoot, service.head.root)                             // Validate head is the new one
 }
+
+func TestService_UpdateHead_NoAtts(t *testing.T) {
+	ctx := context.Background()
+	opts := testServiceOptsWithDB(t)
+	fcs := doublylinkedtree.New()
+	opts = append(opts,
+		WithAttestationPool(attestations.NewPool()),
+		WithStateNotifier(&mockBeaconNode{}),
+		WithForkChoiceStore(fcs),
+	)
+
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+	service.genesisTime = prysmTime.Now().Add(-2 * time.Duration(params.BeaconConfig().SecondsPerSlot) * time.Second)
+	genesisState, pks := util.DeterministicGenesisState(t, 64)
+	require.NoError(t, service.saveGenesisData(ctx, genesisState))
+	copied := genesisState.Copy()
+	// Generate a new block
+	blk, err := util.GenerateFullBlock(copied, pks, util.DefaultBlockGenConfig(), 1)
+	require.NoError(t, err)
+	tRoot, err := blk.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err := blocks.NewSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, service.onBlock(ctx, wsb, tRoot))
+	require.Equal(t, 2, fcs.NodeCount())
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
+	require.Equal(t, tRoot, service.head.root)
+
+	// Insert a new block to forkchoice
+	ojc := &ethpb.Checkpoint{Epoch: 0, Root: params.BeaconConfig().ZeroHash[:]}
+	b, err := util.GenerateFullBlock(genesisState, pks, util.DefaultBlockGenConfig(), 2)
+	require.NoError(t, err)
+	b.Block.ParentRoot = service.originBlockRoot[:]
+	r, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	util.SaveBlock(t, ctx, service.cfg.BeaconDB, b)
+	state, blkRoot, err := prepareForkchoiceState(ctx, 2, r, service.originBlockRoot, [32]byte{'b'}, ojc, ojc)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
+	require.Equal(t, 3, fcs.NodeCount())
+
+	require.Equal(t, 0, service.cfg.AttPool.ForkchoiceAttestationCount())
+	require.NoError(t, err, service.UpdateHead(ctx))
+
+	require.Equal(t, 0, len(service.cfg.AttPool.ForkchoiceAttestations())) // Validate att pool is empty
+	require.Equal(t, r, service.head.root)                                 // Validate head is the new one
+
+}
--- a/beacon-chain/blockchain/receive_block.go
+++ b/beacon-chain/blockchain/receive_block.go
@@ -32,9 +32,9 @@ type SlashingReceiver interface {

 // ReceiveBlock is a function that defines the operations (minus pubsub)
 // that are performed on a received block. The operations consist of:
-//   1. Validate block, apply state transition and update checkpoints
-//   2. Apply fork choice to the processed block
-//   3. Save latest head info
+//  1. Validate block, apply state transition and update checkpoints
+//  2. Apply fork choice to the processed block
+//  3. Save latest head info
 func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.SignedBeaconBlock, blockRoot [32]byte) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.ReceiveBlock")
 	defer span.End()
@@ -150,11 +150,6 @@ func (s *Service) handlePostBlockOperations(b interfaces.BeaconBlock) error {
 		return err
 	}

-	// Add block attestations to the fork choice pool to compute head.
-	if err := s.cfg.AttPool.SaveBlockAttestations(b.Body().Attestations()); err != nil {
-		log.WithError(err).Error("Could not save block attestations for fork choice")
-		return nil
-	}
 	// Mark block exits as seen so we don't include same ones in future blocks.
 	for _, e := range b.Body().VoluntaryExits() {
 		s.cfg.ExitPool.MarkIncluded(e)
--- a/beacon-chain/blockchain/receive_block_test.go
+++ b/beacon-chain/blockchain/receive_block_test.go
@@ -8,7 +8,7 @@ import (

 	blockchainTesting "github.com/prysmaticlabs/prysm/v3/beacon-chain/blockchain/testing"
 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/attestations"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/voluntaryexits"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
@@ -76,9 +76,9 @@ func TestService_ReceiveBlock(t *testing.T) {
 				),
 			},
 			check: func(t *testing.T, s *Service) {
-				if baCount := len(s.cfg.AttPool.BlockAttestations()); baCount != 2 {
+				if baCount := len(s.cfg.AttPool.BlockAttestations()); baCount != 0 {
 					t.Errorf("Did not get the correct number of block attestations saved to the pool. "+
-						"Got %d but wanted %d", baCount, 2)
+						"Got %d but wanted %d", baCount, 0)
 				}
 			},
 		},
@@ -127,13 +127,14 @@ func TestService_ReceiveBlock(t *testing.T) {
 			genesisBlockRoot := bytesutil.ToBytes32(nil)
 			require.NoError(t, beaconDB.SaveState(ctx, genesis, genesisBlockRoot))

+			fc := doublylinkedtree.New()
 			opts := []Option{
 				WithDatabase(beaconDB),
-				WithForkChoiceStore(protoarray.New()),
+				WithForkChoiceStore(fc),
 				WithAttestationPool(attestations.NewPool()),
 				WithExitPool(voluntaryexits.NewPool()),
 				WithStateNotifier(&blockchainTesting.MockStateNotifier{RecordEvents: true}),
-				WithStateGen(stategen.New(beaconDB)),
+				WithStateGen(stategen.New(beaconDB, fc)),
 				WithFinalizedStateAtStartUp(genesis),
 			}
 			s, err := NewService(ctx, opts...)
@@ -166,13 +167,14 @@ func TestService_ReceiveBlockUpdateHead(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	genesisBlockRoot := bytesutil.ToBytes32(nil)
 	require.NoError(t, beaconDB.SaveState(ctx, genesis, genesisBlockRoot))
+	fc := doublylinkedtree.New()
 	opts := []Option{
 		WithDatabase(beaconDB),
-		WithForkChoiceStore(protoarray.New()),
+		WithForkChoiceStore(fc),
 		WithAttestationPool(attestations.NewPool()),
 		WithExitPool(voluntaryexits.NewPool()),
 		WithStateNotifier(&blockchainTesting.MockStateNotifier{RecordEvents: true}),
-		WithStateGen(stategen.New(beaconDB)),
+		WithStateGen(stategen.New(beaconDB, fc)),
 	}

 	s, err := NewService(ctx, opts...)
@@ -242,12 +244,13 @@ func TestService_ReceiveBlockBatch(t *testing.T) {

 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			fc := doublylinkedtree.New()
 			beaconDB := testDB.SetupDB(t)
 			opts := []Option{
 				WithDatabase(beaconDB),
-				WithForkChoiceStore(protoarray.New()),
+				WithForkChoiceStore(fc),
 				WithStateNotifier(&blockchainTesting.MockStateNotifier{RecordEvents: true}),
-				WithStateGen(stategen.New(beaconDB)),
+				WithStateGen(stategen.New(beaconDB, fc)),
 			}
 			s, err := NewService(ctx, opts...)
 			require.NoError(t, err)
--- a/beacon-chain/blockchain/service.go
+++ b/beacon-chain/blockchain/service.go
@@ -21,10 +21,9 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/db"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/execution"
 	f "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice"
-	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/attestations"
+	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/blstoexec"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/slashings"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/voluntaryexits"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/p2p"
@@ -72,6 +71,7 @@ type config struct {
 	AttPool                 attestations.Pool
 	ExitPool                voluntaryexits.PoolManager
 	SlashingPool            slashings.PoolManager
+	BLSToExecPool           blstoexec.PoolManager
 	P2p                     p2p.Broadcaster
 	MaxRoutines             int
 	StateNotifier           statefeed.Notifier
@@ -206,39 +206,33 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 		return errNilFinalizedCheckpoint
 	}

-	var forkChoicer f.ForkChoicer
 	fRoot := s.ensureRootNotZeros(bytesutil.ToBytes32(finalized.Root))
-	if !features.Get().DisableForkchoiceDoublyLinkedTree {
-		forkChoicer = doublylinkedtree.New()
-	} else {
-		forkChoicer = protoarray.New()
-	}
-	s.cfg.ForkChoiceStore = forkChoicer
-	if err := forkChoicer.UpdateJustifiedCheckpoint(&forkchoicetypes.Checkpoint{Epoch: justified.Epoch,
+	if err := s.cfg.ForkChoiceStore.UpdateJustifiedCheckpoint(&forkchoicetypes.Checkpoint{Epoch: justified.Epoch,
 		Root: bytesutil.ToBytes32(justified.Root)}); err != nil {
 		return errors.Wrap(err, "could not update forkchoice's justified checkpoint")
 	}
-	if err := forkChoicer.UpdateFinalizedCheckpoint(&forkchoicetypes.Checkpoint{Epoch: finalized.Epoch,
+	if err := s.cfg.ForkChoiceStore.UpdateFinalizedCheckpoint(&forkchoicetypes.Checkpoint{Epoch: finalized.Epoch,
 		Root: bytesutil.ToBytes32(finalized.Root)}); err != nil {
 		return errors.Wrap(err, "could not update forkchoice's finalized checkpoint")
 	}
-	forkChoicer.SetGenesisTime(uint64(s.genesisTime.Unix()))
+	s.cfg.ForkChoiceStore.SetGenesisTime(uint64(s.genesisTime.Unix()))

 	st, err := s.cfg.StateGen.StateByRoot(s.ctx, fRoot)
 	if err != nil {
 		return errors.Wrap(err, "could not get finalized checkpoint state")
 	}
-	if err := forkChoicer.InsertNode(s.ctx, st, fRoot); err != nil {
+	if err := s.cfg.ForkChoiceStore.InsertNode(s.ctx, st, fRoot); err != nil {
 		return errors.Wrap(err, "could not insert finalized block to forkchoice")
 	}
-
-	lastValidatedCheckpoint, err := s.cfg.BeaconDB.LastValidatedCheckpoint(s.ctx)
-	if err != nil {
-		return errors.Wrap(err, "could not get last validated checkpoint")
-	}
-	if bytes.Equal(finalized.Root, lastValidatedCheckpoint.Root) {
-		if err := forkChoicer.SetOptimisticToValid(s.ctx, fRoot); err != nil {
-			return errors.Wrap(err, "could not set finalized block as validated")
+	if !features.Get().EnableStartOptimistic {
+		lastValidatedCheckpoint, err := s.cfg.BeaconDB.LastValidatedCheckpoint(s.ctx)
+		if err != nil {
+			return errors.Wrap(err, "could not get last validated checkpoint")
+		}
+		if bytes.Equal(finalized.Root, lastValidatedCheckpoint.Root) {
+			if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(s.ctx, fRoot); err != nil {
+				return errors.Wrap(err, "could not set finalized block as validated")
+			}
 		}
 	}
 	// not attempting to save initial sync blocks here, because there shouldn't be any until
--- a/beacon-chain/blockchain/service_test.go
+++ b/beacon-chain/blockchain/service_test.go
@@ -21,11 +21,11 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/execution"
 	mockExecution "github.com/prysmaticlabs/prysm/v3/beacon-chain/execution/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/operations/attestations"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/p2p"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state/stategen"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	"github.com/prysmaticlabs/prysm/v3/config/features"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	consensusblocks "github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/interfaces"
@@ -83,7 +83,7 @@ func setupBeaconChain(t *testing.T, beaconDB db.Database) *Service {
 		srv.Stop()
 	})
 	bState, _ := util.DeterministicGenesisState(t, 10)
-	pbState, err := v1.ProtobufBeaconState(bState.InnerStateUnsafe())
+	pbState, err := state_native.ProtobufBeaconStatePhase0(bState.ToProtoUnsafe())
 	require.NoError(t, err)
 	mockTrie, err := trie.NewTrie(0)
 	require.NoError(t, err)
@@ -117,7 +117,8 @@ func setupBeaconChain(t *testing.T, beaconDB db.Database) *Service {
 	depositCache, err := depositcache.New()
 	require.NoError(t, err)

-	stateGen := stategen.New(beaconDB)
+	fc := doublylinkedtree.New()
+	stateGen := stategen.New(beaconDB, fc)
 	// Safe a state in stategen to purposes of testing a service stop / shutdown.
 	require.NoError(t, stateGen.SaveState(ctx, bytesutil.ToBytes32(bState.FinalizedCheckpoint().Root), bState))

@@ -128,7 +129,7 @@ func setupBeaconChain(t *testing.T, beaconDB db.Database) *Service {
 		WithAttestationPool(attestations.NewPool()),
 		WithP2PBroadcaster(&mockBroadcaster{}),
 		WithStateNotifier(&mockBeaconNode{}),
-		WithForkChoiceStore(doublylinkedtree.New()),
+		WithForkChoiceStore(fc),
 		WithAttestationService(attService),
 		WithStateGen(stateGen),
 	}
@@ -305,8 +306,15 @@ func TestChainService_InitializeChainInfo(t *testing.T) {
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
 	attSrv, err := attestations.NewService(ctx, &attestations.Config{})
 	require.NoError(t, err)
-	stateGen := stategen.New(beaconDB)
-	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stateGen), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
+	fc := doublylinkedtree.New()
+	stateGen := stategen.New(beaconDB, fc)
+	c, err := NewService(ctx,
+		WithForkChoiceStore(fc),
+		WithDatabase(beaconDB),
+		WithStateGen(stateGen),
+		WithAttestationService(attSrv),
+		WithStateNotifier(&mock.MockStateNotifier{}),
+		WithFinalizedStateAtStartUp(headState))
 	require.NoError(t, err)
 	require.NoError(t, stateGen.SaveState(ctx, headRoot, headState))
 	require.NoError(t, c.StartFromSavedState(headState))
@@ -317,7 +325,7 @@ func TestChainService_InitializeChainInfo(t *testing.T) {
 	assert.DeepEqual(t, headBlock, pb, "Head block incorrect")
 	s, err := c.HeadState(ctx)
 	require.NoError(t, err)
-	assert.DeepSSZEqual(t, headState.InnerStateUnsafe(), s.InnerStateUnsafe(), "Head state incorrect")
+	assert.DeepSSZEqual(t, headState.ToProtoUnsafe(), s.ToProtoUnsafe(), "Head state incorrect")
 	assert.Equal(t, c.HeadSlot(), headBlock.Block.Slot, "Head slot incorrect")
 	r, err := c.HeadRoot(context.Background())
 	require.NoError(t, err)
@@ -358,14 +366,21 @@ func TestChainService_InitializeChainInfo_SetHeadAtGenesis(t *testing.T) {
 	}
 	require.NoError(t, beaconDB.SaveStateSummary(ctx, ss))
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: headRoot[:], Epoch: slots.ToEpoch(finalizedSlot)}))
-	stateGen := stategen.New(beaconDB)
-	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stateGen), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
+	fc := doublylinkedtree.New()
+	stateGen := stategen.New(beaconDB, fc)
+	c, err := NewService(ctx,
+		WithForkChoiceStore(fc),
+		WithDatabase(beaconDB),
+		WithStateGen(stateGen),
+		WithAttestationService(attSrv),
+		WithStateNotifier(&mock.MockStateNotifier{}),
+		WithFinalizedStateAtStartUp(headState))
 	require.NoError(t, err)

 	require.NoError(t, c.StartFromSavedState(headState))
 	s, err := c.HeadState(ctx)
 	require.NoError(t, err)
-	assert.DeepSSZEqual(t, headState.InnerStateUnsafe(), s.InnerStateUnsafe(), "Head state incorrect")
+	assert.DeepSSZEqual(t, headState.ToProtoUnsafe(), s.ToProtoUnsafe(), "Head state incorrect")
 	assert.Equal(t, genesisRoot, c.originBlockRoot, "Genesis block root incorrect")
 	pb, err := c.head.block.Proto()
 	require.NoError(t, err)
@@ -375,8 +390,9 @@ func TestChainService_InitializeChainInfo_SetHeadAtGenesis(t *testing.T) {
 func TestChainService_SaveHeadNoDB(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	ctx := context.Background()
+	fc := doublylinkedtree.New()
 	s := &Service{
-		cfg: &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB), ForkChoiceStore: doublylinkedtree.New()},
+		cfg: &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB, fc), ForkChoiceStore: fc},
 	}
 	blk := util.NewBeaconBlock()
 	blk.Block.Slot = 1
@@ -396,25 +412,6 @@ func TestChainService_SaveHeadNoDB(t *testing.T) {
 	}
 }

-func TestHasBlock_ForkChoiceAndDB_ProtoArray(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-	s := &Service{
-		cfg: &config{ForkChoiceStore: protoarray.New(), BeaconDB: beaconDB},
-	}
-	b := util.NewBeaconBlock()
-	r, err := b.Block.HashTreeRoot()
-	require.NoError(t, err)
-	beaconState, err := util.NewBeaconState()
-	require.NoError(t, err)
-	wsb, err := consensusblocks.NewSignedBeaconBlock(b)
-	require.NoError(t, err)
-	require.NoError(t, s.insertBlockToForkchoiceStore(ctx, wsb.Block(), r, beaconState))
-
-	assert.Equal(t, false, s.hasBlock(ctx, [32]byte{}), "Should not have block")
-	assert.Equal(t, true, s.hasBlock(ctx, r), "Should have block")
-}
-
 func TestHasBlock_ForkChoiceAndDB_DoublyLinkedTree(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
@@ -438,7 +435,7 @@ func TestServiceStop_SaveCachedBlocks(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	beaconDB := testDB.SetupDB(t)
 	s := &Service{
-		cfg:            &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
+		cfg:            &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB, doublylinkedtree.New())},
 		ctx:            ctx,
 		cancel:         cancel,
 		initSyncBlocks: make(map[[32]byte]interfaces.SignedBeaconBlock),
@@ -486,27 +483,6 @@ func BenchmarkHasBlockDB(b *testing.B) {
 	}
 }

-func BenchmarkHasBlockForkChoiceStore_ProtoArray(b *testing.B) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(b)
-	s := &Service{
-		cfg: &config{ForkChoiceStore: protoarray.New(), BeaconDB: beaconDB},
-	}
-	blk := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Body: &ethpb.BeaconBlockBody{}}}
-	r, err := blk.Block.HashTreeRoot()
-	require.NoError(b, err)
-	bs := &ethpb.BeaconState{FinalizedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}, CurrentJustifiedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}}
-	beaconState, err := v1.InitializeFromProto(bs)
-	require.NoError(b, err)
-	wsb, err := consensusblocks.NewSignedBeaconBlock(blk)
-	require.NoError(b, err)
-	require.NoError(b, s.insertBlockToForkchoiceStore(ctx, wsb.Block(), r, beaconState))
-
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		require.Equal(b, true, s.cfg.ForkChoiceStore.HasNode(r), "Block is not in fork choice store")
-	}
-}
 func BenchmarkHasBlockForkChoiceStore_DoublyLinkedTree(b *testing.B) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(b)
@@ -517,7 +493,7 @@ func BenchmarkHasBlockForkChoiceStore_DoublyLinkedTree(b *testing.B) {
 	r, err := blk.Block.HashTreeRoot()
 	require.NoError(b, err)
 	bs := &ethpb.BeaconState{FinalizedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}, CurrentJustifiedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}}
-	beaconState, err := v1.InitializeFromProto(bs)
+	beaconState, err := state_native.InitializeFromProtoPhase0(bs)
 	require.NoError(b, err)
 	wsb, err := consensusblocks.NewSignedBeaconBlock(blk)
 	require.NoError(b, err)
@@ -528,3 +504,52 @@ func BenchmarkHasBlockForkChoiceStore_DoublyLinkedTree(b *testing.B) {
 		require.Equal(b, true, s.cfg.ForkChoiceStore.HasNode(r), "Block is not in fork choice store")
 	}
 }
+
+func TestChainService_EverythingOptimistic(t *testing.T) {
+	resetFn := features.InitWithReset(&features.Flags{
+		EnableStartOptimistic: true,
+	})
+	defer resetFn()
+	beaconDB := testDB.SetupDB(t)
+	ctx := context.Background()
+
+	genesis := util.NewBeaconBlock()
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, genesis)
+
+	finalizedSlot := params.BeaconConfig().SlotsPerEpoch*2 + 1
+	headBlock := util.NewBeaconBlock()
+	headBlock.Block.Slot = finalizedSlot
+	headBlock.Block.ParentRoot = bytesutil.PadTo(genesisRoot[:], 32)
+	headState, err := util.NewBeaconState()
+	require.NoError(t, err)
+	require.NoError(t, headState.SetSlot(finalizedSlot))
+	require.NoError(t, headState.SetGenesisValidatorsRoot(params.BeaconConfig().ZeroHash[:]))
+	headRoot, err := headBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
+	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, headBlock)
+	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+	attSrv, err := attestations.NewService(ctx, &attestations.Config{})
+	require.NoError(t, err)
+	fc := doublylinkedtree.New()
+	stateGen := stategen.New(beaconDB, fc)
+	c, err := NewService(ctx,
+		WithForkChoiceStore(fc),
+		WithDatabase(beaconDB),
+		WithStateGen(stateGen),
+		WithAttestationService(attSrv),
+		WithStateNotifier(&mock.MockStateNotifier{}),
+		WithFinalizedStateAtStartUp(headState))
+	require.NoError(t, err)
+	require.NoError(t, stateGen.SaveState(ctx, headRoot, headState))
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+	require.NoError(t, c.StartFromSavedState(headState))
+	require.Equal(t, true, c.cfg.ForkChoiceStore.HasNode(headRoot))
+	op, err := c.cfg.ForkChoiceStore.IsOptimistic(headRoot)
+	require.NoError(t, err)
+	require.Equal(t, true, op)
+}
--- a/beacon-chain/blockchain/state_balance_cache_test.go
+++ b/beacon-chain/blockchain/state_balance_cache_test.go
@@ -7,7 +7,7 @@ import (
 	"testing"

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	v2 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -34,7 +34,7 @@ func testStateFixture(opts ...testStateOpt) state.BeaconState {
 	for _, o := range opts {
 		o(a)
 	}
-	s, _ := v2.InitializeFromProtoUnsafe(a)
+	s, _ := state_native.InitializeFromProtoUnsafeAltair(a)
 	return s
 }

--- a/beacon-chain/blockchain/testing/mock.go
+++ b/beacon-chain/blockchain/testing/mock.go
@@ -174,7 +174,8 @@ func (s *ChainService) ReceiveBlockInitialSync(ctx context.Context, block interf
 	if s.State == nil {
 		return ErrNilState
 	}
-	if !bytes.Equal(s.Root, block.Block().ParentRoot()) {
+	parentRoot := block.Block().ParentRoot()
+	if !bytes.Equal(s.Root, parentRoot[:]) {
 		return errors.Errorf("wanted %#x but got %#x", s.Root, block.Block().ParentRoot())
 	}
 	if err := s.State.SetSlot(block.Block().Slot()); err != nil {
@@ -202,7 +203,8 @@ func (s *ChainService) ReceiveBlockBatch(ctx context.Context, blks []interfaces.
 		return ErrNilState
 	}
 	for _, b := range blks {
-		if !bytes.Equal(s.Root, b.Block().ParentRoot()) {
+		parentRoot := b.Block().ParentRoot()
+		if !bytes.Equal(s.Root, parentRoot[:]) {
 			return errors.Errorf("wanted %#x but got %#x", s.Root, b.Block().ParentRoot())
 		}
 		if err := s.State.SetSlot(b.Block().Slot()); err != nil {
@@ -233,7 +235,8 @@ func (s *ChainService) ReceiveBlock(ctx context.Context, block interfaces.Signed
 	if s.State == nil {
 		return ErrNilState
 	}
-	if !bytes.Equal(s.Root, block.Block().ParentRoot()) {
+	parentRoot := block.Block().ParentRoot()
+	if !bytes.Equal(s.Root, parentRoot[:]) {
 		return errors.Errorf("wanted %#x but got %#x", s.Root, block.Block().ParentRoot())
 	}
 	if err := s.State.SetSlot(block.Block().Slot()); err != nil {
--- a/beacon-chain/blockchain/weak_subjectivity_checks.go
+++ b/beacon-chain/blockchain/weak_subjectivity_checks.go
@@ -30,8 +30,7 @@ type WeakSubjectivityVerifier struct {
 // NewWeakSubjectivityVerifier validates a checkpoint, and if valid, uses it to initialize a weak subjectivity verifier.
 func NewWeakSubjectivityVerifier(wsc *ethpb.Checkpoint, db weakSubjectivityDB) (*WeakSubjectivityVerifier, error) {
 	if wsc == nil || len(wsc.Root) == 0 || wsc.Epoch == 0 {
-		log.Info("--weak-subjectivity-checkpoint not provided. Prysm recommends providing a weak subjectivity checkpoint " +
-			"for nodes synced from genesis, or manual verification of block and state roots for checkpoint sync nodes.")
+		log.Debug("--weak-subjectivity-checkpoint not provided")
 		return &WeakSubjectivityVerifier{
 			enabled: false,
 		}, nil
--- a/beacon-chain/blockchain/weak_subjectivity_checks_test.go
+++ b/beacon-chain/blockchain/weak_subjectivity_checks_test.go
@@ -6,7 +6,7 @@ import (

 	"github.com/pkg/errors"
 	testDB "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
-	"github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/protoarray"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/doubly-linked-tree"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v3/beacon-chain/forkchoice/types"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
@@ -72,7 +72,7 @@ func TestService_VerifyWeakSubjectivityRoot(t *testing.T) {
 			wv, err := NewWeakSubjectivityVerifier(tt.checkpt, beaconDB)
 			require.Equal(t, !tt.disabled, wv.enabled)
 			require.NoError(t, err)
-			fcs := protoarray.New()
+			fcs := doublylinkedtree.New()
 			s := &Service{
 				cfg:        &config{BeaconDB: beaconDB, WeakSubjectivityCheckpt: tt.checkpt, ForkChoiceStore: fcs},
 				wsVerifier: wv,
--- a/beacon-chain/builder/BUILD.bazel
+++ b/beacon-chain/builder/BUILD.bazel
@@ -1,4 +1,4 @@
-load("@prysm//tools/go:def.bzl", "go_library")
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")

 go_library(
    name = "go_default_library",
@@ -16,8 +16,6 @@ go_library(
        "//cmd/beacon-chain/flags:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//encoding/bytesutil:go_default_library",
-        "//network:go_default_library",
-        "//network/authorization:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
@@ -28,3 +26,18 @@ go_library(
        "@io_opencensus_go//trace:go_default_library",
    ],
 )
+
+go_test(
+    name = "go_default_test",
+    srcs = ["service_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//api/client/builder/testing:go_default_library",
+        "//beacon-chain/blockchain/testing:go_default_library",
+        "//beacon-chain/db/testing:go_default_library",
+        "//encoding/bytesutil:go_default_library",
+        "//proto/prysm/v1alpha1:go_default_library",
+        "//testing/assert:go_default_library",
+        "//testing/require:go_default_library",
+    ],
+)
--- a/beacon-chain/builder/metric.go
+++ b/beacon-chain/builder/metric.go
@@ -20,13 +20,6 @@ var (
 			Buckets: []float64{1, 2, 5, 10, 20, 50, 100, 200, 500, 1000},
 		},
 	)
-	getStatusLatency = promauto.NewHistogram(
-		prometheus.HistogramOpts{
-			Name:    "get_status_latency_milliseconds",
-			Help:    "Captures RPC latency for get status in milliseconds",
-			Buckets: []float64{1, 2, 5, 10, 20, 50, 100, 200, 500, 1000},
-		},
-	)
 	registerValidatorLatency = promauto.NewHistogram(
 		prometheus.HistogramOpts{
 			Name:    "register_validator_latency_milliseconds",
--- a/beacon-chain/builder/option.go
+++ b/beacon-chain/builder/option.go
@@ -1,11 +1,10 @@
 package builder

 import (
+	"github.com/prysmaticlabs/prysm/v3/api/client/builder"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/blockchain"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/db"
 	"github.com/prysmaticlabs/prysm/v3/cmd/beacon-chain/flags"
-	"github.com/prysmaticlabs/prysm/v3/network"
-	"github.com/prysmaticlabs/prysm/v3/network/authorization"
 	"github.com/urfave/cli/v2"
 )

@@ -14,22 +13,30 @@ type Option func(s *Service) error
 // FlagOptions for builder service flag configurations.
 func FlagOptions(c *cli.Context) ([]Option, error) {
 	endpoint := c.String(flags.MevRelayEndpoint.Name)
+	var client *builder.Client
+	if endpoint != "" {
+		var err error
+		client, err = builder.NewClient(endpoint)
+		if err != nil {
+			return nil, err
+		}
+	}
 	opts := []Option{
-		WithBuilderEndpoints(endpoint),
+		WithBuilderClient(client),
 	}
 	return opts, nil
 }

-// WithBuilderEndpoints sets the endpoint for the beacon chain builder service.
-func WithBuilderEndpoints(endpoint string) Option {
+// WithBuilderClient sets the builder client for the beacon chain builder service.
+func WithBuilderClient(client builder.BuilderClient) Option {
 	return func(s *Service) error {
-		s.cfg.builderEndpoint = covertEndPoint(endpoint)
+		s.cfg.builderClient = client
 		return nil
 	}
 }

 // WithHeadFetcher gets the head info from chain service.
-func WithHeadFetcher(svc *blockchain.Service) Option {
+func WithHeadFetcher(svc blockchain.HeadFetcher) Option {
 	return func(s *Service) error {
 		s.cfg.headFetcher = svc
 		return nil
@@ -43,12 +50,3 @@ func WithDatabase(beaconDB db.HeadAccessDatabase) Option {
 		return nil
 	}
 }
-
-func covertEndPoint(ep string) network.Endpoint {
-	return network.Endpoint{
-		Url: ep,
-		Auth: network.AuthorizationData{ // Auth is not used for builder.
-			Method: authorization.None,
-			Value:  "",
-		}}
-}
--- a/beacon-chain/builder/service.go
+++ b/beacon-chain/builder/service.go
@@ -2,7 +2,7 @@ package builder

 import (
 	"context"
-	"fmt"
+	"reflect"
 	"time"

 	"github.com/pkg/errors"
@@ -11,7 +11,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/db"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v3/network"
 	v1 "github.com/prysmaticlabs/prysm/v3/proto/engine/v1"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	log "github.com/sirupsen/logrus"
@@ -31,15 +30,15 @@ type BlockBuilder interface {

 // config defines a config struct for dependencies into the service.
 type config struct {
-	builderEndpoint network.Endpoint
-	beaconDB        db.HeadAccessDatabase
-	headFetcher     blockchain.HeadFetcher
+	builderClient builder.BuilderClient
+	beaconDB      db.HeadAccessDatabase
+	headFetcher   blockchain.HeadFetcher
 }

 // Service defines a service that provides a client for interacting with the beacon chain and MEV relay network.
 type Service struct {
 	cfg    *config
-	c      *builder.Client
+	c      builder.BuilderClient
 	ctx    context.Context
 	cancel context.CancelFunc
 }
@@ -57,27 +56,25 @@ func NewService(ctx context.Context, opts ...Option) (*Service, error) {
 			return nil, err
 		}
 	}
-	if s.cfg.builderEndpoint.Url != "" {
-		c, err := builder.NewClient(s.cfg.builderEndpoint.Url)
-		if err != nil {
-			return nil, err
-		}
-		s.c = c
+	if s.cfg.builderClient != nil && !reflect.ValueOf(s.cfg.builderClient).IsNil() {
+		s.c = s.cfg.builderClient

 		// Is the builder up?
 		if err := s.c.Status(ctx); err != nil {
-			return nil, fmt.Errorf("could not connect to builder: %v", err)
+			log.WithError(err).Error("Failed to check builder status")
+		} else {
+			log.WithField("endpoint", s.c.NodeURL()).Info("Builder has been configured")
+			log.Warn("Outsourcing block construction to external builders adds non-trivial delay to block propagation time.  " +
+				"Builder-constructed blocks or fallback blocks may get orphaned. Use at your own risk!")
 		}
-
-		log.WithField("endpoint", c.NodeURL()).Info("Builder has been configured")
-		log.Warn("Outsourcing block construction to external builders adds non-trivial delay to block propagation time.  " +
-			"Builder-constructed blocks or fallback blocks may get orphaned. Use at your own risk!")
 	}
 	return s, nil
 }

 // Start initializes the service.
-func (*Service) Start() {}
+func (s *Service) Start() {
+	go s.pollRelayerStatus(s.ctx)
+}

 // Stop halts the service.
 func (*Service) Stop() error {
@@ -110,19 +107,12 @@ func (s *Service) GetHeader(ctx context.Context, slot types.Slot, parentHash [32

 // Status retrieves the status of the builder relay network.
 func (s *Service) Status() error {
-	ctx, span := trace.StartSpan(context.Background(), "builder.Status")
-	defer span.End()
-	start := time.Now()
-	defer func() {
-		getStatusLatency.Observe(float64(time.Since(start).Milliseconds()))
-	}()
-
 	// Return early if builder isn't initialized in service.
 	if s.c == nil {
 		return nil
 	}

-	return s.c.Status(ctx)
+	return nil
 }

 // RegisterValidator registers a validator with the builder relay network.
@@ -158,7 +148,24 @@ func (s *Service) RegisterValidator(ctx context.Context, reg []*ethpb.SignedVali
 	return s.cfg.beaconDB.SaveRegistrationsByValidatorIDs(ctx, idxs, msgs)
 }

-// Configured returns true if the user has input a builder URL.
+// Configured returns true if the user has configured a builder client.
 func (s *Service) Configured() bool {
-	return s.cfg.builderEndpoint.Url != ""
+	return s.c != nil && !reflect.ValueOf(s.c).IsNil()
+}
+
+func (s *Service) pollRelayerStatus(ctx context.Context) {
+	ticker := time.NewTicker(time.Minute)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ticker.C:
+			if s.c != nil {
+				if err := s.c.Status(ctx); err != nil {
+					log.WithError(err).Error("Failed to call relayer status endpoint, perhaps mev-boost or relayers are down")
+				}
+			}
+		case <-ctx.Done():
+			return
+		}
+	}
 }
--- a/beacon-chain/builder/service_test.go
+++ b/beacon-chain/builder/service_test.go
@@ -0,0 +1,39 @@
+package builder
+
+import (
+	"context"
+	"testing"
+
+	buildertesting "github.com/prysmaticlabs/prysm/v3/api/client/builder/testing"
+	blockchainTesting "github.com/prysmaticlabs/prysm/v3/beacon-chain/blockchain/testing"
+	dbtesting "github.com/prysmaticlabs/prysm/v3/beacon-chain/db/testing"
+	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
+	eth "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/v3/testing/assert"
+	"github.com/prysmaticlabs/prysm/v3/testing/require"
+)
+
+func Test_NewServiceWithBuilder(t *testing.T) {
+	s, err := NewService(context.Background(), WithBuilderClient(&buildertesting.MockClient{}))
+	require.NoError(t, err)
+	assert.Equal(t, true, s.Configured())
+}
+
+func Test_NewServiceWithoutBuilder(t *testing.T) {
+	s, err := NewService(context.Background())
+	require.NoError(t, err)
+	assert.Equal(t, false, s.Configured())
+}
+
+func Test_RegisterValidator(t *testing.T) {
+	ctx := context.Background()
+	db := dbtesting.SetupDB(t)
+	headFetcher := &blockchainTesting.ChainService{}
+	builder := buildertesting.NewClient()
+	s, err := NewService(ctx, WithDatabase(db), WithHeadFetcher(headFetcher), WithBuilderClient(&builder))
+	require.NoError(t, err)
+	pubkey := bytesutil.ToBytes48([]byte("pubkey"))
+	var feeRecipient [20]byte
+	require.NoError(t, s.RegisterValidator(ctx, []*eth.SignedValidatorRegistrationV1{{Message: &eth.ValidatorRegistrationV1{Pubkey: pubkey[:], FeeRecipient: feeRecipient[:]}}}))
+	assert.Equal(t, true, builder.RegisteredVals[pubkey])
+}
--- a/beacon-chain/cache/BUILD.bazel
+++ b/beacon-chain/cache/BUILD.bazel
@@ -73,9 +73,7 @@ go_test(
    embed = [":go_default_library"],
    deps = [
        "//beacon-chain/state:go_default_library",
-        "//beacon-chain/state/v1:go_default_library",
-        "//beacon-chain/state/v2:go_default_library",
-        "//beacon-chain/state/v3:go_default_library",
+        "//beacon-chain/state/state-native:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/primitives:go_default_library",
--- a/beacon-chain/cache/active_balance_test.go
+++ b/beacon-chain/cache/active_balance_test.go
@@ -7,7 +7,7 @@ import (
 	"math"
 	"testing"

-	state "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -24,7 +24,7 @@ func TestBalanceCache_AddGetBalance(t *testing.T) {
 	raw := &ethpb.BeaconState{
 		BlockRoots: blockRoots,
 	}
-	st, err := state.InitializeFromProto(raw)
+	st, err := state_native.InitializeFromProtoPhase0(raw)
 	require.NoError(t, err)

 	cache := NewEffectiveBalanceCache()
@@ -68,7 +68,7 @@ func TestBalanceCache_BalanceKey(t *testing.T) {
 	raw := &ethpb.BeaconState{
 		BlockRoots: blockRoots,
 	}
-	st, err := state.InitializeFromProto(raw)
+	st, err := state_native.InitializeFromProtoPhase0(raw)
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(types.Slot(math.MaxUint64)))

--- a/beacon-chain/cache/checkpoint_state_test.go
+++ b/beacon-chain/cache/checkpoint_state_test.go
@@ -4,7 +4,7 @@ import (
 	"testing"

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
@@ -18,7 +18,7 @@ func TestCheckpointStateCache_StateByCheckpoint(t *testing.T) {
 	cache := NewCheckpointStateCache()

 	cp1 := &ethpb.Checkpoint{Epoch: 1, Root: bytesutil.PadTo([]byte{'A'}, 32)}
-	st, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	st, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		GenesisValidatorsRoot: params.BeaconConfig().ZeroHash[:],
 		Slot:                  64,
 	})
@@ -33,16 +33,16 @@ func TestCheckpointStateCache_StateByCheckpoint(t *testing.T) {
 	s, err = cache.StateByCheckpoint(cp1)
 	require.NoError(t, err)

-	pbState1, err := v1.ProtobufBeaconState(s.InnerStateUnsafe())
+	pbState1, err := state_native.ProtobufBeaconStatePhase0(s.ToProtoUnsafe())
 	require.NoError(t, err)
-	pbstate, err := v1.ProtobufBeaconState(st.InnerStateUnsafe())
+	pbstate, err := state_native.ProtobufBeaconStatePhase0(st.ToProtoUnsafe())
 	require.NoError(t, err)
 	if !proto.Equal(pbState1, pbstate) {
 		t.Error("incorrectly cached state")
 	}

 	cp2 := &ethpb.Checkpoint{Epoch: 2, Root: bytesutil.PadTo([]byte{'B'}, 32)}
-	st2, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	st2, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot: 128,
 	})
 	require.NoError(t, err)
@@ -50,16 +50,16 @@ func TestCheckpointStateCache_StateByCheckpoint(t *testing.T) {

 	s, err = cache.StateByCheckpoint(cp2)
 	require.NoError(t, err)
-	assert.DeepEqual(t, st2.CloneInnerState(), s.CloneInnerState(), "incorrectly cached state")
+	assert.DeepEqual(t, st2.ToProto(), s.ToProto(), "incorrectly cached state")

 	s, err = cache.StateByCheckpoint(cp1)
 	require.NoError(t, err)
-	assert.DeepEqual(t, st.CloneInnerState(), s.CloneInnerState(), "incorrectly cached state")
+	assert.DeepEqual(t, st.ToProto(), s.ToProto(), "incorrectly cached state")
 }

 func TestCheckpointStateCache_MaxSize(t *testing.T) {
 	c := NewCheckpointStateCache()
-	st, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	st, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot: 0,
 	})
 	require.NoError(t, err)
--- a/beacon-chain/cache/depositcache/deposits_cache.go
+++ b/beacon-chain/cache/depositcache/deposits_cache.go
@@ -185,7 +185,21 @@ func (dc *DepositCache) AllDepositContainers(ctx context.Context) []*ethpb.Depos
 	dc.depositsLock.RLock()
 	defer dc.depositsLock.RUnlock()

-	return dc.deposits
+	// Make a shallow copy of the deposits and return that. This way, the
+	// caller can safely iterate over the returned list of deposits without
+	// the possibility of new deposits showing up. If we were to return the
+	// list without a copy, when a new deposit is added to the cache, it
+	// would also be present in the returned value. This could result in a
+	// race condition if the list is being iterated over.
+	//
+	// It's not necessary to make a deep copy of this list because the
+	// deposits in the cache should never be modified. It is still possible
+	// for the caller to modify one of the underlying deposits and modify
+	// the cache, but that's not a race condition. Also, a deep copy would
+	// take too long and use too much memory.
+	deposits := make([]*ethpb.DepositContainer, len(dc.deposits))
+	copy(deposits, dc.deposits)
+	return deposits
 }

 // AllDeposits returns a list of historical deposits until the given block number
--- a/beacon-chain/cache/depositcache/pending_deposits.go
+++ b/beacon-chain/cache/depositcache/pending_deposits.go
@@ -55,7 +55,7 @@ func (dc *DepositCache) PendingDeposits(ctx context.Context, untilBlk *big.Int)

 	depositCntrs := dc.PendingContainers(ctx, untilBlk)

-	var deposits []*ethpb.Deposit
+	deposits := make([]*ethpb.Deposit, 0, len(depositCntrs))
 	for _, dep := range depositCntrs {
 		deposits = append(deposits, dep.Deposit)
 	}
@@ -71,7 +71,7 @@ func (dc *DepositCache) PendingContainers(ctx context.Context, untilBlk *big.Int
 	dc.depositsLock.RLock()
 	defer dc.depositsLock.RUnlock()

-	var depositCntrs []*ethpb.DepositContainer
+	depositCntrs := make([]*ethpb.DepositContainer, 0, len(dc.pendingDeposits))
 	for _, ctnr := range dc.pendingDeposits {
 		if untilBlk == nil || untilBlk.Uint64() >= ctnr.Eth1BlockHeight {
 			depositCntrs = append(depositCntrs, ctnr)
@@ -139,7 +139,7 @@ func (dc *DepositCache) PrunePendingDeposits(ctx context.Context, merkleTreeInde
 	dc.depositsLock.Lock()
 	defer dc.depositsLock.Unlock()

-	var cleanDeposits []*ethpb.DepositContainer
+	cleanDeposits := make([]*ethpb.DepositContainer, 0, len(dc.pendingDeposits))
 	for _, dp := range dc.pendingDeposits {
 		if dp.Index >= merkleTreeIndex {
 			cleanDeposits = append(cleanDeposits, dp)
--- a/beacon-chain/cache/depositsnapshot/BUILD.bazel
+++ b/beacon-chain/cache/depositsnapshot/BUILD.bazel
@@ -0,0 +1,8 @@
+load("@prysm//tools/go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["merkle_tree.go"],
+    importpath = "github.com/prysmaticlabs/prysm/v3/beacon-chain/cache/depositsnapshot",
+    visibility = ["//visibility:public"],
+)
--- a/beacon-chain/cache/depositsnapshot/merkle_tree.go
+++ b/beacon-chain/cache/depositsnapshot/merkle_tree.go
@@ -0,0 +1,19 @@
+package depositsnapshot
+
+const (
+	DepositContractDepth = 32 // Maximum tree depth as defined by EIP-4881.
+)
+
+// MerkleTreeNode is the interface for a Merkle tree.
+type MerkleTreeNode interface {
+	// GetRoot returns the root of the Merkle tree.
+	GetRoot() [32]byte
+	// IsFull returns whether there is space left for deposits.
+	IsFull() bool
+	// Finalize marks deposits of the Merkle tree as finalized.
+	Finalize(deposits uint, depth uint) MerkleTreeNode
+	// GetFinalized returns a list of hashes of all the finalized nodes and the number of deposits.
+	GetFinalized(result [][32]byte) ([][32]byte, uint)
+	// PushLeaf adds a new leaf node at the next available Zero node.
+	PushLeaf(leaf [32]byte, deposits uint, depth uint) MerkleTreeNode
+}
--- a/beacon-chain/cache/skip_slot_cache_test.go
+++ b/beacon-chain/cache/skip_slot_cache_test.go
@@ -6,7 +6,7 @@ import (

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/cache"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v3/testing/assert"
 	"github.com/prysmaticlabs/prysm/v3/testing/require"
@@ -23,7 +23,7 @@ func TestSkipSlotCache_RoundTrip(t *testing.T) {

 	require.NoError(t, c.MarkInProgress(r))

-	s, err = v1.InitializeFromProto(&ethpb.BeaconState{
+	s, err = state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot: 10,
 	})
 	require.NoError(t, err)
@@ -33,5 +33,5 @@ func TestSkipSlotCache_RoundTrip(t *testing.T) {

 	res, err := c.Get(ctx, r)
 	require.NoError(t, err)
-	assert.DeepEqual(t, res.CloneInnerState(), s.CloneInnerState(), "Expected equal protos to return from cache")
+	assert.DeepEqual(t, res.ToProto(), s.ToProto(), "Expected equal protos to return from cache")
 }
--- a/beacon-chain/cache/sync_committee_head_state_test.go
+++ b/beacon-chain/cache/sync_committee_head_state_test.go
@@ -4,9 +4,7 @@ import (
 	"testing"

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
-	v2 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
-	v3 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v3"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -14,21 +12,21 @@ import (
 )

 func TestSyncCommitteeHeadState(t *testing.T) {
-	beaconState, err := v2.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Fork: &ethpb.Fork{
 			PreviousVersion: params.BeaconConfig().GenesisForkVersion,
 			CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
 		},
 	})
 	require.NoError(t, err)
-	phase0State, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	phase0State, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Fork: &ethpb.Fork{
 			PreviousVersion: params.BeaconConfig().GenesisForkVersion,
 			CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
 		},
 	})
 	require.NoError(t, err)
-	bellatrixState, err := v3.InitializeFromProto(&ethpb.BeaconStateBellatrix{
+	bellatrixState, err := state_native.InitializeFromProtoBellatrix(&ethpb.BeaconStateBellatrix{
 		Fork: &ethpb.Fork{
 			PreviousVersion: params.BeaconConfig().GenesisForkVersion,
 			CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
--- a/beacon-chain/core/altair/BUILD.bazel
+++ b/beacon-chain/core/altair/BUILD.bazel
@@ -16,6 +16,7 @@ go_library(
    importpath = "github.com/prysmaticlabs/prysm/v3/beacon-chain/core/altair",
    visibility = [
        "//beacon-chain:__subpackages__",
+        "//cmd/prysmctl/testnet:__pkg__",
        "//testing/endtoend/evaluators:__subpackages__",
        "//testing/spectest:__subpackages__",
        "//testing/util:__pkg__",
@@ -30,7 +31,7 @@ go_library(
        "//beacon-chain/core/time:go_default_library",
        "//beacon-chain/p2p/types:go_default_library",
        "//beacon-chain/state:go_default_library",
-        "//beacon-chain/state/v2:go_default_library",
+        "//beacon-chain/state/state-native:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
@@ -58,6 +59,7 @@ go_test(
        "deposit_test.go",
        "epoch_precompute_test.go",
        "epoch_spec_test.go",
+        "exports_test.go",
        "reward_test.go",
        "sync_committee_test.go",
        "transition_test.go",
@@ -72,8 +74,7 @@ go_test(
        "//beacon-chain/core/time:go_default_library",
        "//beacon-chain/p2p/types:go_default_library",
        "//beacon-chain/state:go_default_library",
-        "//beacon-chain/state/v2:go_default_library",
-        "//beacon-chain/state/v3:go_default_library",
+        "//beacon-chain/state/state-native:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
--- a/beacon-chain/core/altair/attestation.go
+++ b/beacon-chain/core/altair/attestation.go
@@ -82,23 +82,24 @@ func ProcessAttestationNoVerifySignature(
 // the proposer in state.
 //
 // Spec code:
-//     # Update epoch participation flags
-//    if data.target.epoch == get_current_epoch(state):
-//        epoch_participation = state.current_epoch_participation
-//    else:
-//        epoch_participation = state.previous_epoch_participation
 //
-//    proposer_reward_numerator = 0
-//    for index in get_attesting_indices(state, data, attestation.aggregation_bits):
-//        for flag_index, weight in enumerate(PARTICIPATION_FLAG_WEIGHTS):
-//            if flag_index in participation_flag_indices and not has_flag(epoch_participation[index], flag_index):
-//                epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
-//                proposer_reward_numerator += get_base_reward(state, index) * weight
+//	 # Update epoch participation flags
+//	if data.target.epoch == get_current_epoch(state):
+//	    epoch_participation = state.current_epoch_participation
+//	else:
+//	    epoch_participation = state.previous_epoch_participation
 //
-//    # Reward proposer
-//    proposer_reward_denominator = (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT) * WEIGHT_DENOMINATOR // PROPOSER_WEIGHT
-//    proposer_reward = Gwei(proposer_reward_numerator // proposer_reward_denominator)
-//    increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
+//	proposer_reward_numerator = 0
+//	for index in get_attesting_indices(state, data, attestation.aggregation_bits):
+//	    for flag_index, weight in enumerate(PARTICIPATION_FLAG_WEIGHTS):
+//	        if flag_index in participation_flag_indices and not has_flag(epoch_participation[index], flag_index):
+//	            epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
+//	            proposer_reward_numerator += get_base_reward(state, index) * weight
+//
+//	# Reward proposer
+//	proposer_reward_denominator = (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT) * WEIGHT_DENOMINATOR // PROPOSER_WEIGHT
+//	proposer_reward = Gwei(proposer_reward_numerator // proposer_reward_denominator)
+//	increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
 func SetParticipationAndRewardProposer(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -157,12 +158,13 @@ func AddValidatorFlag(flag, flagPosition uint8) (uint8, error) {
 // EpochParticipation sets and returns the proposer reward numerator and epoch participation.
 //
 // Spec code:
-//    proposer_reward_numerator = 0
-//    for index in get_attesting_indices(state, data, attestation.aggregation_bits):
-//        for flag_index, weight in enumerate(PARTICIPATION_FLAG_WEIGHTS):
-//            if flag_index in participation_flag_indices and not has_flag(epoch_participation[index], flag_index):
-//                epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
-//                proposer_reward_numerator += get_base_reward(state, index) * weight
+//
+//	proposer_reward_numerator = 0
+//	for index in get_attesting_indices(state, data, attestation.aggregation_bits):
+//	    for flag_index, weight in enumerate(PARTICIPATION_FLAG_WEIGHTS):
+//	        if flag_index in participation_flag_indices and not has_flag(epoch_participation[index], flag_index):
+//	            epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
+//	            proposer_reward_numerator += get_base_reward(state, index) * weight
 func EpochParticipation(beaconState state.BeaconState, indices []uint64, epochParticipation []byte, participatedFlags map[uint8]bool, totalBalance uint64) (uint64, []byte, error) {
 	cfg := params.BeaconConfig()
 	sourceFlagIndex := cfg.TimelySourceFlagIndex
@@ -218,9 +220,10 @@ func EpochParticipation(beaconState state.BeaconState, indices []uint64, epochPa
 // RewardProposer rewards proposer by increasing proposer's balance with input reward numerator and calculated reward denominator.
 //
 // Spec code:
-//    proposer_reward_denominator = (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT) * WEIGHT_DENOMINATOR // PROPOSER_WEIGHT
-//    proposer_reward = Gwei(proposer_reward_numerator // proposer_reward_denominator)
-//    increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
+//
+//	proposer_reward_denominator = (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT) * WEIGHT_DENOMINATOR // PROPOSER_WEIGHT
+//	proposer_reward = Gwei(proposer_reward_numerator // proposer_reward_denominator)
+//	increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
 func RewardProposer(ctx context.Context, beaconState state.BeaconState, proposerRewardNumerator uint64) error {
 	cfg := params.BeaconConfig()
 	d := (cfg.WeightDenominator - cfg.ProposerWeight) * cfg.WeightDenominator / cfg.ProposerWeight
@@ -238,31 +241,32 @@ func RewardProposer(ctx context.Context, beaconState state.BeaconState, proposer
 //
 // Spec code:
 // def get_attestation_participation_flag_indices(state: BeaconState,
-//                                               data: AttestationData,
-//                                               inclusion_delay: uint64) -> Sequence[int]:
-//    """
-//    Return the flag indices that are satisfied by an attestation.
-//    """
-//    if data.target.epoch == get_current_epoch(state):
-//        justified_checkpoint = state.current_justified_checkpoint
-//    else:
-//        justified_checkpoint = state.previous_justified_checkpoint
 //
-//    # Matching roots
-//    is_matching_source = data.source == justified_checkpoint
-//    is_matching_target = is_matching_source and data.target.root == get_block_root(state, data.target.epoch)
-//    is_matching_head = is_matching_target and data.beacon_block_root == get_block_root_at_slot(state, data.slot)
-//    assert is_matching_source
+//	                                           data: AttestationData,
+//	                                           inclusion_delay: uint64) -> Sequence[int]:
+//	"""
+//	Return the flag indices that are satisfied by an attestation.
+//	"""
+//	if data.target.epoch == get_current_epoch(state):
+//	    justified_checkpoint = state.current_justified_checkpoint
+//	else:
+//	    justified_checkpoint = state.previous_justified_checkpoint
 //
-//    participation_flag_indices = []
-//    if is_matching_source and inclusion_delay <= integer_squareroot(SLOTS_PER_EPOCH):
-//        participation_flag_indices.append(TIMELY_SOURCE_FLAG_INDEX)
-//    if is_matching_target and inclusion_delay <= SLOTS_PER_EPOCH:
-//        participation_flag_indices.append(TIMELY_TARGET_FLAG_INDEX)
-//    if is_matching_head and inclusion_delay == MIN_ATTESTATION_INCLUSION_DELAY:
-//        participation_flag_indices.append(TIMELY_HEAD_FLAG_INDEX)
+//	# Matching roots
+//	is_matching_source = data.source == justified_checkpoint
+//	is_matching_target = is_matching_source and data.target.root == get_block_root(state, data.target.epoch)
+//	is_matching_head = is_matching_target and data.beacon_block_root == get_block_root_at_slot(state, data.slot)
+//	assert is_matching_source
 //
-//    return participation_flag_indices
+//	participation_flag_indices = []
+//	if is_matching_source and inclusion_delay <= integer_squareroot(SLOTS_PER_EPOCH):
+//	    participation_flag_indices.append(TIMELY_SOURCE_FLAG_INDEX)
+//	if is_matching_target and inclusion_delay <= SLOTS_PER_EPOCH:
+//	    participation_flag_indices.append(TIMELY_TARGET_FLAG_INDEX)
+//	if is_matching_head and inclusion_delay == MIN_ATTESTATION_INCLUSION_DELAY:
+//	    participation_flag_indices.append(TIMELY_HEAD_FLAG_INDEX)
+//
+//	return participation_flag_indices
 func AttestationParticipationFlagIndices(beaconState state.BeaconState, data *ethpb.AttestationData, delay types.Slot) (map[uint8]bool, error) {
 	currEpoch := time.CurrentEpoch(beaconState)
 	var justifiedCheckpt *ethpb.Checkpoint
@@ -304,9 +308,10 @@ func AttestationParticipationFlagIndices(beaconState state.BeaconState, data *et
 // MatchingStatus returns the matching statues for attestation data's source target and head.
 //
 // Spec code:
-//    is_matching_source = data.source == justified_checkpoint
-//    is_matching_target = is_matching_source and data.target.root == get_block_root(state, data.target.epoch)
-//    is_matching_head = is_matching_target and data.beacon_block_root == get_block_root_at_slot(state, data.slot)
+//
+//	is_matching_source = data.source == justified_checkpoint
+//	is_matching_target = is_matching_source and data.target.root == get_block_root(state, data.target.epoch)
+//	is_matching_head = is_matching_target and data.beacon_block_root == get_block_root_at_slot(state, data.slot)
 func MatchingStatus(beaconState state.BeaconState, data *ethpb.AttestationData, cp *ethpb.Checkpoint) (matchedSrc, matchedTgt, matchedHead bool, err error) {
 	matchedSrc = attestation.CheckPointIsEqual(data.Source, cp)

--- a/beacon-chain/core/altair/attestation_test.go
+++ b/beacon-chain/core/altair/attestation_test.go
@@ -12,7 +12,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
@@ -419,7 +419,7 @@ func TestFuzzProcessAttestationsNoVerify_10000(t *testing.T) {
 		if b.Block == nil {
 			b.Block = &ethpb.BeaconBlockAltair{}
 		}
-		s, err := stateAltair.InitializeFromProtoUnsafe(st)
+		s, err := state_native.InitializeFromProtoUnsafeAltair(st)
 		require.NoError(t, err)
 		if b.Block == nil || b.Block.Body == nil {
 			continue
--- a/beacon-chain/core/altair/block.go
+++ b/beacon-chain/core/altair/block.go
@@ -9,7 +9,6 @@ import (
 	p2pType "github.com/prysmaticlabs/prysm/v3/beacon-chain/p2p/types"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
-	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -20,32 +19,33 @@ import (
 //
 // Spec code:
 // def process_sync_aggregate(state: BeaconState, sync_aggregate: SyncAggregate) -> None:
-//    # Verify sync committee aggregate signature signing over the previous slot block root
-//    committee_pubkeys = state.current_sync_committee.pubkeys
-//    participant_pubkeys = [pubkey for pubkey, bit in zip(committee_pubkeys, sync_aggregate.sync_committee_bits) if bit]
-//    previous_slot = max(state.slot, Slot(1)) - Slot(1)
-//    domain = get_domain(state, DOMAIN_SYNC_COMMITTEE, compute_epoch_at_slot(previous_slot))
-//    signing_root = compute_signing_root(get_block_root_at_slot(state, previous_slot), domain)
-//    assert eth2_fast_aggregate_verify(participant_pubkeys, signing_root, sync_aggregate.sync_committee_signature)
 //
-//    # Compute participant and proposer rewards
-//    total_active_increments = get_total_active_balance(state) // EFFECTIVE_BALANCE_INCREMENT
-//    total_base_rewards = Gwei(get_base_reward_per_increment(state) * total_active_increments)
-//    max_participant_rewards = Gwei(total_base_rewards * SYNC_REWARD_WEIGHT // WEIGHT_DENOMINATOR // SLOTS_PER_EPOCH)
-//    participant_reward = Gwei(max_participant_rewards // SYNC_COMMITTEE_SIZE)
-//    proposer_reward = Gwei(participant_reward * PROPOSER_WEIGHT // (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT))
+//	# Verify sync committee aggregate signature signing over the previous slot block root
+//	committee_pubkeys = state.current_sync_committee.pubkeys
+//	participant_pubkeys = [pubkey for pubkey, bit in zip(committee_pubkeys, sync_aggregate.sync_committee_bits) if bit]
+//	previous_slot = max(state.slot, Slot(1)) - Slot(1)
+//	domain = get_domain(state, DOMAIN_SYNC_COMMITTEE, compute_epoch_at_slot(previous_slot))
+//	signing_root = compute_signing_root(get_block_root_at_slot(state, previous_slot), domain)
+//	assert eth2_fast_aggregate_verify(participant_pubkeys, signing_root, sync_aggregate.sync_committee_signature)
 //
-//    # Apply participant and proposer rewards
-//    all_pubkeys = [v.pubkey for v in state.validators]
-//    committee_indices = [ValidatorIndex(all_pubkeys.index(pubkey)) for pubkey in state.current_sync_committee.pubkeys]
-//    for participant_index, participation_bit in zip(committee_indices, sync_aggregate.sync_committee_bits):
-//        if participation_bit:
-//            increase_balance(state, participant_index, participant_reward)
-//            increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
-//        else:
-//            decrease_balance(state, participant_index, participant_reward)
+//	# Compute participant and proposer rewards
+//	total_active_increments = get_total_active_balance(state) // EFFECTIVE_BALANCE_INCREMENT
+//	total_base_rewards = Gwei(get_base_reward_per_increment(state) * total_active_increments)
+//	max_participant_rewards = Gwei(total_base_rewards * SYNC_REWARD_WEIGHT // WEIGHT_DENOMINATOR // SLOTS_PER_EPOCH)
+//	participant_reward = Gwei(max_participant_rewards // SYNC_COMMITTEE_SIZE)
+//	proposer_reward = Gwei(participant_reward * PROPOSER_WEIGHT // (WEIGHT_DENOMINATOR - PROPOSER_WEIGHT))
+//
+//	# Apply participant and proposer rewards
+//	all_pubkeys = [v.pubkey for v in state.validators]
+//	committee_indices = [ValidatorIndex(all_pubkeys.index(pubkey)) for pubkey in state.current_sync_committee.pubkeys]
+//	for participant_index, participation_bit in zip(committee_indices, sync_aggregate.sync_committee_bits):
+//	    if participation_bit:
+//	        increase_balance(state, participant_index, participant_reward)
+//	        increase_balance(state, get_beacon_proposer_index(state), proposer_reward)
+//	    else:
+//	        decrease_balance(state, participant_index, participant_reward)
 func ProcessSyncAggregate(ctx context.Context, s state.BeaconState, sync *ethpb.SyncAggregate) (state.BeaconState, error) {
-	votedKeys, votedIndices, didntVoteIndices, err := FilterSyncCommitteeVotes(s, sync)
+	s, votedKeys, err := processSyncAggregate(ctx, s, sync)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not filter sync committee votes")
 	}
@@ -53,50 +53,70 @@ func ProcessSyncAggregate(ctx context.Context, s state.BeaconState, sync *ethpb.
 	if err := VerifySyncCommitteeSig(s, votedKeys, sync.SyncCommitteeSignature); err != nil {
 		return nil, errors.Wrap(err, "could not verify sync committee signature")
 	}
-
-	return ApplySyncRewardsPenalties(ctx, s, votedIndices, didntVoteIndices)
+	return s, nil
 }

-// FilterSyncCommitteeVotes filters the validator public keys and indices for the ones that voted and didn't vote.
-func FilterSyncCommitteeVotes(s state.BeaconState, sync *ethpb.SyncAggregate) (
-	votedKeys []bls.PublicKey,
-	votedIndices []types.ValidatorIndex,
-	didntVoteIndices []types.ValidatorIndex,
-	err error) {
+// processSyncAggregate applies all the logic in the spec function `process_sync_aggregate` except
+// verifying the BLS signatures. It returns the modified beacons state and the list of validators'
+// public keys that voted, for future signature verification.
+func processSyncAggregate(ctx context.Context, s state.BeaconState, sync *ethpb.SyncAggregate) (
+	state.BeaconState,
+	[]bls.PublicKey,
+	error) {
 	currentSyncCommittee, err := s.CurrentSyncCommittee()
 	if err != nil {
-		return nil, nil, nil, err
+		return nil, nil, err
 	}
 	if currentSyncCommittee == nil {
-		return nil, nil, nil, errors.New("nil current sync committee in state")
+		return nil, nil, errors.New("nil current sync committee in state")
 	}
 	committeeKeys := currentSyncCommittee.Pubkeys
 	if sync.SyncCommitteeBits.Len() > uint64(len(committeeKeys)) {
-		return nil, nil, nil, errors.New("bits length exceeds committee length")
+		return nil, nil, errors.New("bits length exceeds committee length")
 	}
-	votedKeys = make([]bls.PublicKey, 0, len(committeeKeys))
-	votedIndices = make([]types.ValidatorIndex, 0, len(committeeKeys))
-	didntVoteIndices = make([]types.ValidatorIndex, 0) // No allocation. Expect most votes.
+	votedKeys := make([]bls.PublicKey, 0, len(committeeKeys))

+	activeBalance, err := helpers.TotalActiveBalance(s)
+	if err != nil {
+		return nil, nil, err
+	}
+	proposerReward, participantReward, err := SyncRewards(activeBalance)
+	if err != nil {
+		return nil, nil, err
+	}
+	proposerIndex, err := helpers.BeaconProposerIndex(ctx, s)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	earnedProposerReward := uint64(0)
 	for i := uint64(0); i < sync.SyncCommitteeBits.Len(); i++ {
 		vIdx, exists := s.ValidatorIndexByPubkey(bytesutil.ToBytes48(committeeKeys[i]))
 		// Impossible scenario.
 		if !exists {
-			return nil, nil, nil, errors.New("validator public key does not exist in state")
+			return nil, nil, errors.New("validator public key does not exist in state")
 		}

 		if sync.SyncCommitteeBits.BitAt(i) {
 			pubKey, err := bls.PublicKeyFromBytes(committeeKeys[i])
 			if err != nil {
-				return nil, nil, nil, err
+				return nil, nil, err
 			}
 			votedKeys = append(votedKeys, pubKey)
-			votedIndices = append(votedIndices, vIdx)
+			if err := helpers.IncreaseBalance(s, vIdx, participantReward); err != nil {
+				return nil, nil, err
+			}
+			earnedProposerReward += proposerReward
 		} else {
-			didntVoteIndices = append(didntVoteIndices, vIdx)
+			if err := helpers.DecreaseBalance(s, vIdx, participantReward); err != nil {
+				return nil, nil, err
+			}
 		}
 	}
-	return
+	if err := helpers.IncreaseBalance(s, proposerIndex, earnedProposerReward); err != nil {
+		return nil, nil, err
+	}
+	return s, votedKeys, err
 }

 // VerifySyncCommitteeSig verifies sync committee signature `syncSig` is valid with respect to public keys `syncKeys`.
@@ -125,43 +145,6 @@ func VerifySyncCommitteeSig(s state.BeaconState, syncKeys []bls.PublicKey, syncS
 	return nil
 }

-// ApplySyncRewardsPenalties applies rewards and penalties for proposer and sync committee participants.
-func ApplySyncRewardsPenalties(ctx context.Context, s state.BeaconState, votedIndices, didntVoteIndices []types.ValidatorIndex) (state.BeaconState, error) {
-	activeBalance, err := helpers.TotalActiveBalance(s)
-	if err != nil {
-		return nil, err
-	}
-	proposerReward, participantReward, err := SyncRewards(activeBalance)
-	if err != nil {
-		return nil, err
-	}
-
-	// Apply sync committee rewards.
-	earnedProposerReward := uint64(0)
-	for _, index := range votedIndices {
-		if err := helpers.IncreaseBalance(s, index, participantReward); err != nil {
-			return nil, err
-		}
-		earnedProposerReward += proposerReward
-	}
-	// Apply proposer rewards.
-	proposerIndex, err := helpers.BeaconProposerIndex(ctx, s)
-	if err != nil {
-		return nil, err
-	}
-	if err := helpers.IncreaseBalance(s, proposerIndex, earnedProposerReward); err != nil {
-		return nil, err
-	}
-	// Apply sync committee penalties.
-	for _, index := range didntVoteIndices {
-		if err := helpers.DecreaseBalance(s, index, participantReward); err != nil {
-			return nil, err
-		}
-	}
-
-	return s, nil
-}
-
 // SyncRewards returns the proposer reward and the sync participant reward given the total active balance in state.
 func SyncRewards(activeBalance uint64) (proposerReward, participantReward uint64, err error) {
 	cfg := params.BeaconConfig()
--- a/beacon-chain/core/altair/block_test.go
+++ b/beacon-chain/core/altair/block_test.go
@@ -168,7 +168,36 @@ func TestProcessSyncCommittee_MixParticipation_GoodSignature(t *testing.T) {
 	require.NoError(t, err)
 }

-func TestProcessSyncCommittee_FilterSyncCommitteeVotes(t *testing.T) {
+// This is a regression test #11696
+func TestProcessSyncCommittee_DontPrecompute(t *testing.T) {
+	beaconState, _ := util.DeterministicGenesisStateAltair(t, params.BeaconConfig().MaxValidatorsPerCommittee)
+	require.NoError(t, beaconState.SetSlot(1))
+	committee, err := altair.NextSyncCommittee(context.Background(), beaconState)
+	require.NoError(t, err)
+	committeeKeys := committee.Pubkeys
+	committeeKeys[1] = committeeKeys[0]
+	require.NoError(t, beaconState.SetCurrentSyncCommittee(committee))
+	idx, ok := beaconState.ValidatorIndexByPubkey(bytesutil.ToBytes48(committeeKeys[0]))
+	require.Equal(t, true, ok)
+
+	syncBits := bitfield.NewBitvector512()
+	for i := range syncBits {
+		syncBits[i] = 0xFF
+	}
+	syncBits.SetBitAt(0, false)
+	syncAggregate := &ethpb.SyncAggregate{
+		SyncCommitteeBits: syncBits,
+	}
+	require.NoError(t, beaconState.UpdateBalancesAtIndex(idx, 0))
+	st, votedKeys, err := altair.ProcessSyncAggregateEported(context.Background(), beaconState, syncAggregate)
+	require.NoError(t, err)
+	require.Equal(t, 511, len(votedKeys))
+	require.DeepEqual(t, committeeKeys[0], votedKeys[0].Marshal())
+	balances := st.Balances()
+	require.Equal(t, uint64(988), balances[idx])
+}
+
+func TestProcessSyncCommittee_processSyncAggregate(t *testing.T) {
 	beaconState, _ := util.DeterministicGenesisStateAltair(t, params.BeaconConfig().MaxValidatorsPerCommittee)
 	require.NoError(t, beaconState.SetSlot(1))
 	committee, err := altair.NextSyncCommittee(context.Background(), beaconState)
@@ -183,25 +212,40 @@ func TestProcessSyncCommittee_FilterSyncCommitteeVotes(t *testing.T) {
 		SyncCommitteeBits: syncBits,
 	}

-	votedKeys, votedIndices, didntVoteIndices, err := altair.FilterSyncCommitteeVotes(beaconState, syncAggregate)
+	st, votedKeys, err := altair.ProcessSyncAggregateEported(context.Background(), beaconState, syncAggregate)
 	require.NoError(t, err)
 	votedMap := make(map[[fieldparams.BLSPubkeyLength]byte]bool)
 	for _, key := range votedKeys {
 		votedMap[bytesutil.ToBytes48(key.Marshal())] = true
 	}
 	require.Equal(t, int(syncBits.Len()/2), len(votedKeys))
-	require.Equal(t, int(syncBits.Len()/2), len(votedIndices))
-	require.Equal(t, int(syncBits.Len()/2), len(didntVoteIndices))
+
+	currentSyncCommittee, err := st.CurrentSyncCommittee()
+	require.NoError(t, err)
+	committeeKeys := currentSyncCommittee.Pubkeys
+	balances := st.Balances()
+
+	proposerIndex, err := helpers.BeaconProposerIndex(context.Background(), beaconState)
+	require.NoError(t, err)

 	for i := 0; i < len(syncBits); i++ {
 		if syncBits.BitAt(uint64(i)) {
-			pk := beaconState.PubkeyAtIndex(votedIndices[i])
+			pk := bytesutil.ToBytes48(committeeKeys[i])
 			require.DeepEqual(t, true, votedMap[pk])
+			idx, ok := st.ValidatorIndexByPubkey(pk)
+			require.Equal(t, true, ok)
+			require.Equal(t, uint64(32000000988), balances[idx])
 		} else {
-			pk := beaconState.PubkeyAtIndex(didntVoteIndices[i])
+			pk := bytesutil.ToBytes48(committeeKeys[i])
 			require.DeepEqual(t, false, votedMap[pk])
+			idx, ok := st.ValidatorIndexByPubkey(pk)
+			require.Equal(t, true, ok)
+			if idx != proposerIndex {
+				require.Equal(t, uint64(31999999012), balances[idx])
+			}
 		}
 	}
+	require.Equal(t, uint64(32000035108), balances[proposerIndex])
 }

 func Test_VerifySyncCommitteeSig(t *testing.T) {
@@ -240,22 +284,6 @@ func Test_VerifySyncCommitteeSig(t *testing.T) {
 	require.NoError(t, altair.VerifySyncCommitteeSig(beaconState, pks, aggregatedSig))
 }

-func Test_ApplySyncRewardsPenalties(t *testing.T) {
-	beaconState, _ := util.DeterministicGenesisStateAltair(t, params.BeaconConfig().MaxValidatorsPerCommittee)
-	beaconState, err := altair.ApplySyncRewardsPenalties(context.Background(), beaconState,
-		[]types.ValidatorIndex{0, 1}, // voted
-		[]types.ValidatorIndex{2, 3}) // didn't vote
-	require.NoError(t, err)
-	balances := beaconState.Balances()
-	require.Equal(t, uint64(32000000988), balances[0])
-	require.Equal(t, balances[0], balances[1])
-	require.Equal(t, uint64(31999999012), balances[2])
-	require.Equal(t, balances[2], balances[3])
-	proposerIndex, err := helpers.BeaconProposerIndex(context.Background(), beaconState)
-	require.NoError(t, err)
-	require.Equal(t, uint64(32000000282), balances[proposerIndex])
-}
-
 func Test_SyncRewards(t *testing.T) {
 	tests := []struct {
 		name                  string
--- a/beacon-chain/core/altair/deposit_fuzz_test.go
+++ b/beacon-chain/core/altair/deposit_fuzz_test.go
@@ -6,7 +6,7 @@ import (

 	fuzz "github.com/google/gofuzz"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/altair"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v3/testing/require"
 )
@@ -21,7 +21,7 @@ func TestFuzzProcessDeposits_10000(t *testing.T) {
 		for i := range deposits {
 			fuzzer.Fuzz(deposits[i])
 		}
-		s, err := stateAltair.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafeAltair(state)
 		require.NoError(t, err)
 		r, err := altair.ProcessDeposits(ctx, s, deposits)
 		if err != nil && r != nil {
@@ -38,7 +38,7 @@ func TestFuzzProcessDeposit_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(deposit)
-		s, err := stateAltair.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafeAltair(state)
 		require.NoError(t, err)
 		r, err := altair.ProcessDeposit(s, deposit, true)
 		if err != nil && r != nil {
--- a/beacon-chain/core/altair/deposit_test.go
+++ b/beacon-chain/core/altair/deposit_test.go
@@ -6,7 +6,7 @@ import (

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/altair"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	"github.com/prysmaticlabs/prysm/v3/container/trie"
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
@@ -29,7 +29,7 @@ func TestProcessDeposits_SameValidatorMultipleDepositsSameBlock(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -62,7 +62,7 @@ func TestProcessDeposits_MerkleBranchFailsVerification(t *testing.T) {
 	require.NoError(t, err, "Could not generate proof")

 	deposit.Proof = proof
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Eth1Data: &ethpb.Eth1Data{
 			DepositRoot: []byte{0},
 			BlockHash:   []byte{1},
@@ -87,7 +87,7 @@ func TestProcessDeposits_AddsNewValidatorDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -145,7 +145,7 @@ func TestProcessDeposits_RepeatedDeposit_IncreasesValidatorBalance(t *testing.T)
 	balances := []uint64{0, 50}
 	root, err := depositTrie.HashTreeRoot()
 	require.NoError(t, err)
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data: &ethpb.Eth1Data{
@@ -173,7 +173,7 @@ func TestProcessDeposit_AddsNewValidatorDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -216,7 +216,7 @@ func TestProcessDeposit_SkipsInvalidDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	beaconState, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
--- a/beacon-chain/core/altair/epoch_precompute.go
+++ b/beacon-chain/core/altair/epoch_precompute.go
@@ -68,9 +68,10 @@ func InitializePrecomputeValidators(ctx context.Context, beaconState state.Beaco
 // For fully inactive validators and perfect active validators, the effect is the same as before Altair.
 // For a validator is inactive and the chain fails to finalize, the inactivity score increases by a fixed number, the total loss after N epochs is proportional to N**2/2.
 // For imperfectly active validators. The inactivity score's behavior is specified by this function:
-//    If a validator fails to submit an attestation with the correct target, their inactivity score goes up by 4.
-//    If they successfully submit an attestation with the correct source and target, their inactivity score drops by 1
-//    If the chain has recently finalized, each validator's score drops by 16.
+//
+//	If a validator fails to submit an attestation with the correct target, their inactivity score goes up by 4.
+//	If they successfully submit an attestation with the correct source and target, their inactivity score drops by 1
+//	If the chain has recently finalized, each validator's score drops by 16.
 func ProcessInactivityScores(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -132,12 +133,13 @@ func ProcessInactivityScores(
 // it also tracks and updates epoch attesting balances.
 // Spec code:
 // if epoch == get_current_epoch(state):
-//        epoch_participation = state.current_epoch_participation
-//    else:
-//        epoch_participation = state.previous_epoch_participation
-//    active_validator_indices = get_active_validator_indices(state, epoch)
-//    participating_indices = [i for i in active_validator_indices if has_flag(epoch_participation[i], flag_index)]
-//    return set(filter(lambda index: not state.validators[index].slashed, participating_indices))
+//
+//	    epoch_participation = state.current_epoch_participation
+//	else:
+//	    epoch_participation = state.previous_epoch_participation
+//	active_validator_indices = get_active_validator_indices(state, epoch)
+//	participating_indices = [i for i in active_validator_indices if has_flag(epoch_participation[i], flag_index)]
+//	return set(filter(lambda index: not state.validators[index].slashed, participating_indices))
 func ProcessEpochParticipation(
 	ctx context.Context,
 	beaconState state.BeaconState,
--- a/beacon-chain/core/altair/epoch_precompute_test.go
+++ b/beacon-chain/core/altair/epoch_precompute_test.go
@@ -7,8 +7,7 @@ import (

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/epoch/precompute"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
-	v3 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v3"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
@@ -18,7 +17,7 @@ import (

 func TestInitializeEpochValidators_Ok(t *testing.T) {
 	ffe := params.BeaconConfig().FarFutureEpoch
-	s, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	s, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Slot: params.BeaconConfig().SlotsPerEpoch,
 		// Validator 0 is slashed
 		// Validator 1 is withdrawable
@@ -66,7 +65,7 @@ func TestInitializeEpochValidators_Ok(t *testing.T) {

 func TestInitializeEpochValidators_Overflow(t *testing.T) {
 	ffe := params.BeaconConfig().FarFutureEpoch
-	s, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	s, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Slot: params.BeaconConfig().SlotsPerEpoch,
 		Validators: []*ethpb.Validator{
 			{WithdrawableEpoch: ffe, ExitEpoch: ffe, EffectiveBalance: math.MaxUint64},
@@ -80,7 +79,7 @@ func TestInitializeEpochValidators_Overflow(t *testing.T) {
 }

 func TestInitializeEpochValidators_BadState(t *testing.T) {
-	s, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	s, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators:       []*ethpb.Validator{{}},
 		InactivityScores: []uint64{},
 	})
@@ -150,7 +149,7 @@ func TestProcessEpochParticipation_InactiveValidator(t *testing.T) {
 		}
 		return b
 	}
-	st, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	st, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Slot: 2 * params.BeaconConfig().SlotsPerEpoch,
 		Validators: []*ethpb.Validator{
 			{EffectiveBalance: params.BeaconConfig().MaxEffectiveBalance},                                                  // Inactive
@@ -468,7 +467,7 @@ func testState() (state.BeaconState, error) {
 		}
 		return b
 	}
-	return stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	return state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Slot: 2 * params.BeaconConfig().SlotsPerEpoch,
 		Validators: []*ethpb.Validator{
 			{EffectiveBalance: params.BeaconConfig().MaxEffectiveBalance, ExitEpoch: params.BeaconConfig().FarFutureEpoch},
@@ -505,7 +504,7 @@ func testStateBellatrix() (state.BeaconState, error) {
 		}
 		return b
 	}
-	return v3.InitializeFromProto(&ethpb.BeaconStateBellatrix{
+	return state_native.InitializeFromProtoBellatrix(&ethpb.BeaconStateBellatrix{
 		Slot: 2 * params.BeaconConfig().SlotsPerEpoch,
 		Validators: []*ethpb.Validator{
 			{EffectiveBalance: params.BeaconConfig().MaxEffectiveBalance, ExitEpoch: params.BeaconConfig().FarFutureEpoch},
--- a/beacon-chain/core/altair/epoch_spec.go
+++ b/beacon-chain/core/altair/epoch_spec.go
@@ -14,10 +14,11 @@ import (
 //
 // Spec code:
 // def process_sync_committee_updates(state: BeaconState) -> None:
-//    next_epoch = get_current_epoch(state) + Epoch(1)
-//    if next_epoch % EPOCHS_PER_SYNC_COMMITTEE_PERIOD == 0:
-//        state.current_sync_committee = state.next_sync_committee
-//        state.next_sync_committee = get_next_sync_committee(state)
+//
+//	next_epoch = get_current_epoch(state) + Epoch(1)
+//	if next_epoch % EPOCHS_PER_SYNC_COMMITTEE_PERIOD == 0:
+//	    state.current_sync_committee = state.next_sync_committee
+//	    state.next_sync_committee = get_next_sync_committee(state)
 func ProcessSyncCommitteeUpdates(ctx context.Context, beaconState state.BeaconState) (state.BeaconState, error) {
 	nextEpoch := time.NextEpoch(beaconState)
 	if nextEpoch%params.BeaconConfig().EpochsPerSyncCommitteePeriod == 0 {
@@ -46,8 +47,9 @@ func ProcessSyncCommitteeUpdates(ctx context.Context, beaconState state.BeaconSt
 //
 // Spec code:
 // def process_participation_flag_updates(state: BeaconState) -> None:
-//    state.previous_epoch_participation = state.current_epoch_participation
-//    state.current_epoch_participation = [ParticipationFlags(0b0000_0000) for _ in range(len(state.validators))]
+//
+//	state.previous_epoch_participation = state.current_epoch_participation
+//	state.current_epoch_participation = [ParticipationFlags(0b0000_0000) for _ in range(len(state.validators))]
 func ProcessParticipationFlagUpdates(beaconState state.BeaconState) (state.BeaconState, error) {
 	c, err := beaconState.CurrentEpochParticipation()
 	if err != nil {
--- a/beacon-chain/core/altair/epoch_spec_test.go
+++ b/beacon-chain/core/altair/epoch_spec_test.go
@@ -10,7 +10,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/epoch"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/time"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
@@ -103,7 +103,7 @@ func TestProcessSlashings_NotSlashed(t *testing.T) {
 		Balances:   []uint64{params.BeaconConfig().MaxEffectiveBalance},
 		Slashings:  []uint64{0, 1e9},
 	}
-	s, err := stateAltair.InitializeFromProto(base)
+	s, err := state_native.InitializeFromProtoAltair(base)
 	require.NoError(t, err)
 	newState, err := epoch.ProcessSlashings(s, params.BeaconConfig().ProportionalSlashingMultiplierAltair)
 	require.NoError(t, err)
@@ -174,7 +174,7 @@ func TestProcessSlashings_SlashedLess(t *testing.T) {
 		t.Run(fmt.Sprint(i), func(t *testing.T) {
 			helpers.ClearCache()
 			original := proto.Clone(tt.state)
-			s, err := stateAltair.InitializeFromProto(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)
@@ -190,7 +190,7 @@ func TestProcessSlashings_BadValue(t *testing.T) {
 		Balances:   []uint64{params.BeaconConfig().MaxEffectiveBalance},
 		Slashings:  []uint64{math.MaxUint64, 1e9},
 	}
-	s, err := stateAltair.InitializeFromProto(base)
+	s, err := state_native.InitializeFromProtoAltair(base)
 	require.NoError(t, err)
 	_, err = epoch.ProcessSlashings(s, params.BeaconConfig().ProportionalSlashingMultiplierAltair)
 	require.ErrorContains(t, "addition overflows", err)
--- a/beacon-chain/core/altair/exports_test.go
+++ b/beacon-chain/core/altair/exports_test.go
@@ -0,0 +1,3 @@
+package altair
+
+var ProcessSyncAggregateEported = processSyncAggregate
--- a/beacon-chain/core/altair/reward.go
+++ b/beacon-chain/core/altair/reward.go
@@ -13,16 +13,17 @@ import (
 // individual validator's base reward.
 //
 // Spec code:
-//  def get_base_reward(state: BeaconState, index: ValidatorIndex) -> Gwei:
-//    """
-//    Return the base reward for the validator defined by ``index`` with respect to the current ``state``.
 //
-//    Note: An optimally performing validator can earn one base reward per epoch over a long time horizon.
-//    This takes into account both per-epoch (e.g. attestation) and intermittent duties (e.g. block proposal
-//    and sync committees).
-//    """
-//    increments = state.validators[index].effective_balance // EFFECTIVE_BALANCE_INCREMENT
-//    return Gwei(increments * get_base_reward_per_increment(state))
+//	def get_base_reward(state: BeaconState, index: ValidatorIndex) -> Gwei:
+//	  """
+//	  Return the base reward for the validator defined by ``index`` with respect to the current ``state``.
+//
+//	  Note: An optimally performing validator can earn one base reward per epoch over a long time horizon.
+//	  This takes into account both per-epoch (e.g. attestation) and intermittent duties (e.g. block proposal
+//	  and sync committees).
+//	  """
+//	  increments = state.validators[index].effective_balance // EFFECTIVE_BALANCE_INCREMENT
+//	  return Gwei(increments * get_base_reward_per_increment(state))
 func BaseReward(s state.ReadOnlyBeaconState, index types.ValidatorIndex) (uint64, error) {
 	totalBalance, err := helpers.TotalActiveBalance(s)
 	if err != nil {
@@ -50,7 +51,8 @@ func BaseRewardWithTotalBalance(s state.ReadOnlyBeaconState, index types.Validat
 //
 // Spec code:
 // def get_base_reward_per_increment(state: BeaconState) -> Gwei:
-//    return Gwei(EFFECTIVE_BALANCE_INCREMENT * BASE_REWARD_FACTOR // integer_squareroot(get_total_active_balance(state)))
+//
+//	return Gwei(EFFECTIVE_BALANCE_INCREMENT * BASE_REWARD_FACTOR // integer_squareroot(get_total_active_balance(state)))
 func BaseRewardPerIncrement(activeBalance uint64) (uint64, error) {
 	if activeBalance == 0 {
 		return 0, errors.New("active balance can't be 0")
--- a/beacon-chain/core/altair/reward_test.go
+++ b/beacon-chain/core/altair/reward_test.go
@@ -5,6 +5,7 @@ import (
 	"testing"

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/altair"
+	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
@@ -13,6 +14,7 @@ import (
 )

 func Test_BaseReward(t *testing.T) {
+	helpers.ClearCache()
 	genState := func(valCount uint64) state.ReadOnlyBeaconState {
 		s, _ := util.DeterministicGenesisStateAltair(t, valCount)
 		return s
@@ -66,6 +68,7 @@ func Test_BaseReward(t *testing.T) {
 }

 func Test_BaseRewardWithTotalBalance(t *testing.T) {
+	helpers.ClearCache()
 	s, _ := util.DeterministicGenesisStateAltair(t, 1)
 	tests := []struct {
 		name          string
@@ -137,6 +140,7 @@ func Test_BaseRewardWithTotalBalance(t *testing.T) {
 }

 func Test_BaseRewardPerIncrement(t *testing.T) {
+	helpers.ClearCache()
 	tests := []struct {
 		name          string
 		activeBalance uint64
--- a/beacon-chain/core/altair/sync_committee.go
+++ b/beacon-chain/core/altair/sync_committee.go
@@ -47,13 +47,14 @@ func ValidateNilSyncContribution(s *ethpb.SignedContributionAndProof) error {
 //
 // Spec code:
 // def get_next_sync_committee(state: BeaconState) -> SyncCommittee:
-//    """
-//    Return the next sync committee, with possible pubkey duplicates.
-//    """
-//    indices = get_next_sync_committee_indices(state)
-//    pubkeys = [state.validators[index].pubkey for index in indices]
-//    aggregate_pubkey = bls.AggregatePKs(pubkeys)
-//    return SyncCommittee(pubkeys=pubkeys, aggregate_pubkey=aggregate_pubkey)
+//
+//	"""
+//	Return the next sync committee, with possible pubkey duplicates.
+//	"""
+//	indices = get_next_sync_committee_indices(state)
+//	pubkeys = [state.validators[index].pubkey for index in indices]
+//	aggregate_pubkey = bls.AggregatePKs(pubkeys)
+//	return SyncCommittee(pubkeys=pubkeys, aggregate_pubkey=aggregate_pubkey)
 func NextSyncCommittee(ctx context.Context, s state.BeaconState) (*ethpb.SyncCommittee, error) {
 	indices, err := NextSyncCommitteeIndices(ctx, s)
 	if err != nil {
@@ -78,26 +79,27 @@ func NextSyncCommittee(ctx context.Context, s state.BeaconState) (*ethpb.SyncCom
 //
 // Spec code:
 // def get_next_sync_committee_indices(state: BeaconState) -> Sequence[ValidatorIndex]:
-//    """
-//    Return the sync committee indices, with possible duplicates, for the next sync committee.
-//    """
-//    epoch = Epoch(get_current_epoch(state) + 1)
 //
-//    MAX_RANDOM_BYTE = 2**8 - 1
-//    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
-//    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]
-//        effective_balance = state.validators[candidate_index].effective_balance
-//        if effective_balance * MAX_RANDOM_BYTE >= MAX_EFFECTIVE_BALANCE * random_byte:
-//            sync_committee_indices.append(candidate_index)
-//        i += 1
-//    return sync_committee_indices
+//	"""
+//	Return the sync committee indices, with possible duplicates, for the next sync committee.
+//	"""
+//	epoch = Epoch(get_current_epoch(state) + 1)
+//
+//	MAX_RANDOM_BYTE = 2**8 - 1
+//	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
+//	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]
+//	    effective_balance = state.validators[candidate_index].effective_balance
+//	    if effective_balance * MAX_RANDOM_BYTE >= MAX_EFFECTIVE_BALANCE * random_byte:
+//	        sync_committee_indices.append(candidate_index)
+//	    i += 1
+//	return sync_committee_indices
 func NextSyncCommitteeIndices(ctx context.Context, s state.BeaconState) ([]types.ValidatorIndex, error) {
 	epoch := coreTime.NextEpoch(s)
 	indices, err := helpers.ActiveValidatorIndices(ctx, s, epoch)
@@ -144,18 +146,19 @@ func NextSyncCommitteeIndices(ctx context.Context, s state.BeaconState) ([]types
 // SyncSubCommitteePubkeys returns the pubkeys participating in a sync subcommittee.
 //
 // def get_sync_subcommittee_pubkeys(state: BeaconState, subcommittee_index: uint64) -> Sequence[BLSPubkey]:
-//    # Committees assigned to `slot` sign for `slot - 1`
-//    # This creates the exceptional logic below when transitioning between sync committee periods
-//    next_slot_epoch = compute_epoch_at_slot(Slot(state.slot + 1))
-//    if compute_sync_committee_period(get_current_epoch(state)) == compute_sync_committee_period(next_slot_epoch):
-//        sync_committee = state.current_sync_committee
-//    else:
-//        sync_committee = state.next_sync_committee
 //
-//    # Return pubkeys for the subcommittee index
-//    sync_subcommittee_size = SYNC_COMMITTEE_SIZE // SYNC_COMMITTEE_SUBNET_COUNT
-//    i = subcommittee_index * sync_subcommittee_size
-//    return sync_committee.pubkeys[i:i + sync_subcommittee_size]
+//	# Committees assigned to `slot` sign for `slot - 1`
+//	# This creates the exceptional logic below when transitioning between sync committee periods
+//	next_slot_epoch = compute_epoch_at_slot(Slot(state.slot + 1))
+//	if compute_sync_committee_period(get_current_epoch(state)) == compute_sync_committee_period(next_slot_epoch):
+//	    sync_committee = state.current_sync_committee
+//	else:
+//	    sync_committee = state.next_sync_committee
+//
+//	# Return pubkeys for the subcommittee index
+//	sync_subcommittee_size = SYNC_COMMITTEE_SIZE // SYNC_COMMITTEE_SUBNET_COUNT
+//	i = subcommittee_index * sync_subcommittee_size
+//	return sync_committee.pubkeys[i:i + sync_subcommittee_size]
 func SyncSubCommitteePubkeys(syncCommittee *ethpb.SyncCommittee, subComIdx types.CommitteeIndex) ([][]byte, error) {
 	cfg := params.BeaconConfig()
 	subCommSize := cfg.SyncCommitteeSize / cfg.SyncCommitteeSubnetCount
@@ -172,8 +175,9 @@ func SyncSubCommitteePubkeys(syncCommittee *ethpb.SyncCommittee, subComIdx types
 // aggregator.
 //
 // def is_sync_committee_aggregator(signature: BLSSignature) -> bool:
-//    modulo = max(1, SYNC_COMMITTEE_SIZE // SYNC_COMMITTEE_SUBNET_COUNT // TARGET_AGGREGATORS_PER_SYNC_SUBCOMMITTEE)
-//    return bytes_to_uint64(hash(signature)[0:8]) % modulo == 0
+//
+//	modulo = max(1, SYNC_COMMITTEE_SIZE // SYNC_COMMITTEE_SUBNET_COUNT // TARGET_AGGREGATORS_PER_SYNC_SUBCOMMITTEE)
+//	return bytes_to_uint64(hash(signature)[0:8]) % modulo == 0
 func IsSyncCommitteeAggregator(sig []byte) (bool, error) {
 	if len(sig) != fieldparams.BLSSignatureLength {
 		return false, errors.New("incorrect sig length")
--- a/beacon-chain/core/altair/sync_committee_test.go
+++ b/beacon-chain/core/altair/sync_committee_test.go
@@ -8,8 +8,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/altair"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	stateAltair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
-	v2 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
@@ -28,7 +27,7 @@ func TestSyncCommitteeIndices_CanGet(t *testing.T) {
 				EffectiveBalance: params.BeaconConfig().MinDepositAmount,
 			}
 		}
-		st, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+		st, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 			Validators:  validators,
 			RandaoMixes: make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
 		})
@@ -46,14 +45,6 @@ func TestSyncCommitteeIndices_CanGet(t *testing.T) {
 		wantErr   bool
 		errString string
 	}{
-		{
-			name: "nil inner state",
-			args: args{
-				state: &v2.BeaconState{},
-			},
-			wantErr:   true,
-			errString: "nil inner state",
-		},
 		{
 			name: "genesis validator count, epoch 0",
 			args: args{
@@ -103,7 +94,7 @@ func TestSyncCommitteeIndices_DifferentPeriods(t *testing.T) {
 				EffectiveBalance: params.BeaconConfig().MinDepositAmount,
 			}
 		}
-		st, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+		st, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 			Validators:  validators,
 			RandaoMixes: make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
 		})
@@ -140,7 +131,7 @@ func TestSyncCommittee_CanGet(t *testing.T) {
 				PublicKey:        blsKey.PublicKey().Marshal(),
 			}
 		}
-		st, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+		st, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 			Validators:  validators,
 			RandaoMixes: make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
 		})
@@ -158,14 +149,6 @@ func TestSyncCommittee_CanGet(t *testing.T) {
 		wantErr   bool
 		errString string
 	}{
-		{
-			name: "nil inner state",
-			args: args{
-				state: &v2.BeaconState{},
-			},
-			wantErr:   true,
-			errString: "nil inner state",
-		},
 		{
 			name: "genesis validator count, epoch 0",
 			args: args{
@@ -395,7 +378,7 @@ func getState(t *testing.T, count uint64) state.BeaconState {
 			PublicKey:        blsKey.PublicKey().Marshal(),
 		}
 	}
-	st, err := stateAltair.InitializeFromProto(&ethpb.BeaconStateAltair{
+	st, err := state_native.InitializeFromProtoAltair(&ethpb.BeaconStateAltair{
 		Validators:  validators,
 		RandaoMixes: make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
 	})
--- a/beacon-chain/core/altair/transition.go
+++ b/beacon-chain/core/altair/transition.go
@@ -15,18 +15,19 @@ import (
 //
 // Spec code:
 // def process_epoch(state: BeaconState) -> None:
-//    process_justification_and_finalization(state)  # [Modified in Altair]
-//    process_inactivity_updates(state)  # [New in Altair]
-//    process_rewards_and_penalties(state)  # [Modified in Altair]
-//    process_registry_updates(state)
-//    process_slashings(state)  # [Modified in Altair]
-//    process_eth1_data_reset(state)
-//    process_effective_balance_updates(state)
-//    process_slashings_reset(state)
-//    process_randao_mixes_reset(state)
-//    process_historical_roots_update(state)
-//    process_participation_flag_updates(state)  # [New in Altair]
-//    process_sync_committee_updates(state)  # [New in Altair]
+//
+//	process_justification_and_finalization(state)  # [Modified in Altair]
+//	process_inactivity_updates(state)  # [New in Altair]
+//	process_rewards_and_penalties(state)  # [Modified in Altair]
+//	process_registry_updates(state)
+//	process_slashings(state)  # [Modified in Altair]
+//	process_eth1_data_reset(state)
+//	process_effective_balance_updates(state)
+//	process_slashings_reset(state)
+//	process_randao_mixes_reset(state)
+//	process_historical_roots_update(state)
+//	process_participation_flag_updates(state)  # [New in Altair]
+//	process_sync_committee_updates(state)  # [New in Altair]
 func ProcessEpoch(ctx context.Context, state state.BeaconState) (state.BeaconState, error) {
 	ctx, span := trace.StartSpan(ctx, "altair.ProcessEpoch")
 	defer span.End()
--- a/beacon-chain/core/altair/upgrade.go
+++ b/beacon-chain/core/altair/upgrade.go
@@ -6,7 +6,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/state"
-	statealtair "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v2"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1/attestation"
@@ -16,52 +16,53 @@ import (
 //
 // Spec code:
 // def upgrade_to_altair(pre: phase0.BeaconState) -> BeaconState:
-//    epoch = phase0.get_current_epoch(pre)
-//    post = BeaconState(
-//        # Versioning
-//        genesis_time=pre.genesis_time,
-//        genesis_validators_root=pre.genesis_validators_root,
-//        slot=pre.slot,
-//        fork=Fork(
-//            previous_version=pre.fork.current_version,
-//            current_version=ALTAIR_FORK_VERSION,
-//            epoch=epoch,
-//        ),
-//        # History
-//        latest_block_header=pre.latest_block_header,
-//        block_roots=pre.block_roots,
-//        state_roots=pre.state_roots,
-//        historical_roots=pre.historical_roots,
-//        # Eth1
-//        eth1_data=pre.eth1_data,
-//        eth1_data_votes=pre.eth1_data_votes,
-//        eth1_deposit_index=pre.eth1_deposit_index,
-//        # Registry
-//        validators=pre.validators,
-//        balances=pre.balances,
-//        # Randomness
-//        randao_mixes=pre.randao_mixes,
-//        # Slashings
-//        slashings=pre.slashings,
-//        # Participation
-//        previous_epoch_participation=[ParticipationFlags(0b0000_0000) for _ in range(len(pre.validators))],
-//        current_epoch_participation=[ParticipationFlags(0b0000_0000) for _ in range(len(pre.validators))],
-//        # Finality
-//        justification_bits=pre.justification_bits,
-//        previous_justified_checkpoint=pre.previous_justified_checkpoint,
-//        current_justified_checkpoint=pre.current_justified_checkpoint,
-//        finalized_checkpoint=pre.finalized_checkpoint,
-//        # Inactivity
-//        inactivity_scores=[uint64(0) for _ in range(len(pre.validators))],
-//    )
-//    # Fill in previous epoch participation from the pre state's pending attestations
-//    translate_participation(post, pre.previous_epoch_attestations)
 //
-//    # Fill in sync committees
-//    # Note: A duplicate committee is assigned for the current and next committee at the fork boundary
-//    post.current_sync_committee = get_next_sync_committee(post)
-//    post.next_sync_committee = get_next_sync_committee(post)
-//    return post
+//	epoch = phase0.get_current_epoch(pre)
+//	post = BeaconState(
+//	    # Versioning
+//	    genesis_time=pre.genesis_time,
+//	    genesis_validators_root=pre.genesis_validators_root,
+//	    slot=pre.slot,
+//	    fork=Fork(
+//	        previous_version=pre.fork.current_version,
+//	        current_version=ALTAIR_FORK_VERSION,
+//	        epoch=epoch,
+//	    ),
+//	    # History
+//	    latest_block_header=pre.latest_block_header,
+//	    block_roots=pre.block_roots,
+//	    state_roots=pre.state_roots,
+//	    historical_roots=pre.historical_roots,
+//	    # Eth1
+//	    eth1_data=pre.eth1_data,
+//	    eth1_data_votes=pre.eth1_data_votes,
+//	    eth1_deposit_index=pre.eth1_deposit_index,
+//	    # Registry
+//	    validators=pre.validators,
+//	    balances=pre.balances,
+//	    # Randomness
+//	    randao_mixes=pre.randao_mixes,
+//	    # Slashings
+//	    slashings=pre.slashings,
+//	    # Participation
+//	    previous_epoch_participation=[ParticipationFlags(0b0000_0000) for _ in range(len(pre.validators))],
+//	    current_epoch_participation=[ParticipationFlags(0b0000_0000) for _ in range(len(pre.validators))],
+//	    # Finality
+//	    justification_bits=pre.justification_bits,
+//	    previous_justified_checkpoint=pre.previous_justified_checkpoint,
+//	    current_justified_checkpoint=pre.current_justified_checkpoint,
+//	    finalized_checkpoint=pre.finalized_checkpoint,
+//	    # Inactivity
+//	    inactivity_scores=[uint64(0) for _ in range(len(pre.validators))],
+//	)
+//	# Fill in previous epoch participation from the pre state's pending attestations
+//	translate_participation(post, pre.previous_epoch_attestations)
+//
+//	# Fill in sync committees
+//	# Note: A duplicate committee is assigned for the current and next committee at the fork boundary
+//	post.current_sync_committee = get_next_sync_committee(post)
+//	post.next_sync_committee = get_next_sync_committee(post)
+//	return post
 func UpgradeToAltair(ctx context.Context, state state.BeaconState) (state.BeaconState, error) {
 	epoch := time.CurrentEpoch(state)

@@ -95,7 +96,7 @@ func UpgradeToAltair(ctx context.Context, state state.BeaconState) (state.Beacon
 		InactivityScores:            make([]uint64, numValidators),
 	}

-	newState, err := statealtair.InitializeFromProtoUnsafe(s)
+	newState, err := state_native.InitializeFromProtoUnsafeAltair(s)
 	if err != nil {
 		return nil, err
 	}
@@ -126,17 +127,18 @@ func UpgradeToAltair(ctx context.Context, state state.BeaconState) (state.Beacon
 //
 // Spec code:
 // def translate_participation(state: BeaconState, pending_attestations: Sequence[phase0.PendingAttestation]) -> None:
-//    for attestation in pending_attestations:
-//        data = attestation.data
-//        inclusion_delay = attestation.inclusion_delay
-//        # Translate attestation inclusion info to flag indices
-//        participation_flag_indices = get_attestation_participation_flag_indices(state, data, inclusion_delay)
 //
-//        # Apply flags to all attesting validators
-//        epoch_participation = state.previous_epoch_participation
-//        for index in get_attesting_indices(state, data, attestation.aggregation_bits):
-//            for flag_index in participation_flag_indices:
-//                epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
+//	for attestation in pending_attestations:
+//	    data = attestation.data
+//	    inclusion_delay = attestation.inclusion_delay
+//	    # Translate attestation inclusion info to flag indices
+//	    participation_flag_indices = get_attestation_participation_flag_indices(state, data, inclusion_delay)
+//
+//	    # Apply flags to all attesting validators
+//	    epoch_participation = state.previous_epoch_participation
+//	    for index in get_attesting_indices(state, data, attestation.aggregation_bits):
+//	        for flag_index in participation_flag_indices:
+//	            epoch_participation[index] = add_flag(epoch_participation[index], flag_index)
 func TranslateParticipation(ctx context.Context, state state.BeaconState, atts []*ethpb.PendingAttestation) (state.BeaconState, error) {
 	epochParticipation, err := state.PreviousEpochParticipation()
 	if err != nil {
--- a/beacon-chain/core/blocks/BUILD.bazel
+++ b/beacon-chain/core/blocks/BUILD.bazel
@@ -41,8 +41,8 @@ go_library(
        "//contracts/deposit:go_default_library",
        "//crypto/bls:go_default_library",
        "//crypto/hash:go_default_library",
-        "//crypto/hash/htr:go_default_library",
        "//encoding/bytesutil:go_default_library",
+        "//encoding/ssz:go_default_library",
        "//math:go_default_library",
        "//network/forks:go_default_library",
        "//proto/engine/v1:go_default_library",
@@ -70,6 +70,7 @@ go_test(
        "deposit_test.go",
        "eth1_data_test.go",
        "exit_test.go",
+        "exports_test.go",
        "genesis_test.go",
        "header_test.go",
        "payload_test.go",
@@ -89,14 +90,16 @@ go_test(
        "//beacon-chain/core/validators:go_default_library",
        "//beacon-chain/p2p/types:go_default_library",
        "//beacon-chain/state:go_default_library",
-        "//beacon-chain/state/v1:go_default_library",
+        "//beacon-chain/state/state-native:go_default_library",
        "//config/fieldparams:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//container/trie:go_default_library",
        "//crypto/bls:go_default_library",
-        "//crypto/hash/htr:go_default_library",
+        "//crypto/bls/common:go_default_library",
+        "//crypto/hash:go_default_library",
        "//encoding/bytesutil:go_default_library",
        "//encoding/ssz:go_default_library",
        "//proto/engine/v1:go_default_library",
--- a/beacon-chain/core/blocks/attestation.go
+++ b/beacon-chain/core/blocks/attestation.go
@@ -185,19 +185,20 @@ func VerifyAttestationSignature(ctx context.Context, beaconState state.ReadOnlyB
 // VerifyIndexedAttestation determines the validity of an indexed attestation.
 //
 // Spec pseudocode definition:
-//  def is_valid_indexed_attestation(state: BeaconState, indexed_attestation: IndexedAttestation) -> bool:
-//    """
-//    Check if ``indexed_attestation`` is not empty, has sorted and unique indices and has a valid aggregate signature.
-//    """
-//    # Verify indices are sorted and unique
-//    indices = indexed_attestation.attesting_indices
-//    if len(indices) == 0 or not indices == sorted(set(indices)):
-//        return False
-//    # Verify aggregate signature
-//    pubkeys = [state.validators[i].pubkey for i in indices]
-//    domain = get_domain(state, DOMAIN_BEACON_ATTESTER, indexed_attestation.data.target.epoch)
-//    signing_root = compute_signing_root(indexed_attestation.data, domain)
-//    return bls.FastAggregateVerify(pubkeys, signing_root, indexed_attestation.signature)
+//
+//	def is_valid_indexed_attestation(state: BeaconState, indexed_attestation: IndexedAttestation) -> bool:
+//	  """
+//	  Check if ``indexed_attestation`` is not empty, has sorted and unique indices and has a valid aggregate signature.
+//	  """
+//	  # Verify indices are sorted and unique
+//	  indices = indexed_attestation.attesting_indices
+//	  if len(indices) == 0 or not indices == sorted(set(indices)):
+//	      return False
+//	  # Verify aggregate signature
+//	  pubkeys = [state.validators[i].pubkey for i in indices]
+//	  domain = get_domain(state, DOMAIN_BEACON_ATTESTER, indexed_attestation.data.target.epoch)
+//	  signing_root = compute_signing_root(indexed_attestation.data, domain)
+//	  return bls.FastAggregateVerify(pubkeys, signing_root, indexed_attestation.signature)
 func VerifyIndexedAttestation(ctx context.Context, beaconState state.ReadOnlyBeaconState, indexedAtt *ethpb.IndexedAttestation) error {
 	ctx, span := trace.StartSpan(ctx, "core.VerifyIndexedAttestation")
 	defer span.End()
--- a/beacon-chain/core/blocks/attestation_regression_test.go
+++ b/beacon-chain/core/blocks/attestation_regression_test.go
@@ -7,7 +7,7 @@ import (

 	"github.com/prysmaticlabs/go-bitfield"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	ethpb "github.com/prysmaticlabs/prysm/v3/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v3/testing/assert"
@@ -36,7 +36,7 @@ func TestProcessAttestationNoVerifySignature_BeaconFuzzIssue78(t *testing.T) {
 	if err := spb.UnmarshalSSZ(stateData); err != nil {
 		t.Fatal(err)
 	}
-	st, err := v1.InitializeFromProtoUnsafe(spb)
+	st, err := state_native.InitializeFromProtoUnsafePhase0(spb)
 	if err != nil {
 		t.Fatal(err)
 	}
--- a/beacon-chain/core/blocks/attestation_test.go
+++ b/beacon-chain/core/blocks/attestation_test.go
@@ -8,7 +8,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
@@ -192,7 +192,7 @@ func TestConvertToIndexed_OK(t *testing.T) {
 		}
 	}

-	state, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	state, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot:        5,
 		Validators:  validators,
 		RandaoMixes: make([][]byte, params.BeaconConfig().EpochsPerHistoricalVector),
@@ -250,7 +250,7 @@ func TestVerifyIndexedAttestation_OK(t *testing.T) {
 		}
 	}

-	state, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	state, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot:       5,
 		Validators: validators,
 		Fork: &ethpb.Fork{
@@ -337,7 +337,7 @@ func TestValidateIndexedAttestation_AboveMaxLength(t *testing.T) {
 	}

 	want := "validator indices count exceeds MAX_VALIDATORS_PER_COMMITTEE"
-	st, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
+	st, err := state_native.InitializeFromProtoUnsafePhase0(&ethpb.BeaconState{})
 	require.NoError(t, err)
 	err = blocks.VerifyIndexedAttestation(context.Background(), st, indexedAtt1)
 	assert.ErrorContains(t, want, err)
--- a/beacon-chain/core/blocks/attester_slashing.go
+++ b/beacon-chain/core/blocks/attester_slashing.go
@@ -22,20 +22,21 @@ import (
 // Casper FFG slashing conditions if any slashable events occurred.
 //
 // Spec pseudocode definition:
-//   def process_attester_slashing(state: BeaconState, attester_slashing: AttesterSlashing) -> None:
-//    attestation_1 = attester_slashing.attestation_1
-//    attestation_2 = attester_slashing.attestation_2
-//    assert is_slashable_attestation_data(attestation_1.data, attestation_2.data)
-//    assert is_valid_indexed_attestation(state, attestation_1)
-//    assert is_valid_indexed_attestation(state, attestation_2)
 //
-//    slashed_any = False
-//    indices = set(attestation_1.attesting_indices).intersection(attestation_2.attesting_indices)
-//    for index in sorted(indices):
-//        if is_slashable_validator(state.validators[index], get_current_epoch(state)):
-//            slash_validator(state, index)
-//            slashed_any = True
-//    assert slashed_any
+//	def process_attester_slashing(state: BeaconState, attester_slashing: AttesterSlashing) -> None:
+//	 attestation_1 = attester_slashing.attestation_1
+//	 attestation_2 = attester_slashing.attestation_2
+//	 assert is_slashable_attestation_data(attestation_1.data, attestation_2.data)
+//	 assert is_valid_indexed_attestation(state, attestation_1)
+//	 assert is_valid_indexed_attestation(state, attestation_2)
+//
+//	 slashed_any = False
+//	 indices = set(attestation_1.attesting_indices).intersection(attestation_2.attesting_indices)
+//	 for index in sorted(indices):
+//	     if is_slashable_validator(state.validators[index], get_current_epoch(state)):
+//	         slash_validator(state, index)
+//	         slashed_any = True
+//	 assert slashed_any
 func ProcessAttesterSlashings(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -83,7 +84,7 @@ func ProcessAttesterSlashing(
 				slashingQuotient = cfg.MinSlashingPenaltyQuotient
 			case beaconState.Version() == version.Altair:
 				slashingQuotient = cfg.MinSlashingPenaltyQuotientAltair
-			case beaconState.Version() == version.Bellatrix:
+			case beaconState.Version() == version.Bellatrix, beaconState.Version() == version.Capella:
 				slashingQuotient = cfg.MinSlashingPenaltyQuotientBellatrix
 			default:
 				return nil, errors.New("unknown state version")
@@ -132,16 +133,17 @@ func VerifyAttesterSlashing(ctx context.Context, beaconState state.ReadOnlyBeaco
 // IsSlashableAttestationData verifies a slashing against the Casper Proof of Stake FFG rules.
 //
 // Spec pseudocode definition:
-//   def is_slashable_attestation_data(data_1: AttestationData, data_2: AttestationData) -> bool:
-//    """
-//    Check if ``data_1`` and ``data_2`` are slashable according to Casper FFG rules.
-//    """
-//    return (
-//        # Double vote
-//        (data_1 != data_2 and data_1.target.epoch == data_2.target.epoch) or
-//        # Surround vote
-//        (data_1.source.epoch < data_2.source.epoch and data_2.target.epoch < data_1.target.epoch)
-//    )
+//
+//	def is_slashable_attestation_data(data_1: AttestationData, data_2: AttestationData) -> bool:
+//	 """
+//	 Check if ``data_1`` and ``data_2`` are slashable according to Casper FFG rules.
+//	 """
+//	 return (
+//	     # Double vote
+//	     (data_1 != data_2 and data_1.target.epoch == data_2.target.epoch) or
+//	     # Surround vote
+//	     (data_1.source.epoch < data_2.source.epoch and data_2.target.epoch < data_1.target.epoch)
+//	 )
 func IsSlashableAttestationData(data1, data2 *ethpb.AttestationData) bool {
 	if data1 == nil || data2 == nil || data1.Target == nil || data2.Target == nil || data1.Source == nil || data2.Source == nil {
 		return false
--- a/beacon-chain/core/blocks/attester_slashing_test.go
+++ b/beacon-chain/core/blocks/attester_slashing_test.go
@@ -7,7 +7,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
 	v "github.com/prysmaticlabs/prysm/v3/beacon-chain/core/validators"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
@@ -46,7 +46,7 @@ func TestProcessAttesterSlashings_DataNotSlashable(t *testing.T) {
 	var registry []*ethpb.Validator
 	currentSlot := types.Slot(0)

-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Slot:       currentSlot,
 	})
@@ -65,7 +65,7 @@ func TestProcessAttesterSlashings_IndexedAttestationFailedToVerify(t *testing.T)
 	var registry []*ethpb.Validator
 	currentSlot := types.Slot(0)

-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Slot:       currentSlot,
 	})
@@ -302,3 +302,72 @@ func TestProcessAttesterSlashings_AppliesCorrectStatusBellatrix(t *testing.T) {
 	require.Equal(t, uint64(31000000000), newState.Balances()[1])
 	require.Equal(t, uint64(32000000000), newState.Balances()[2])
 }
+
+func TestProcessAttesterSlashings_AppliesCorrectStatusCapella(t *testing.T) {
+	beaconState, privKeys := util.DeterministicGenesisStateCapella(t, 100)
+	for _, vv := range beaconState.Validators() {
+		vv.WithdrawableEpoch = types.Epoch(params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	att1 := util.HydrateIndexedAttestation(&ethpb.IndexedAttestation{
+		Data: &ethpb.AttestationData{
+			Source: &ethpb.Checkpoint{Epoch: 1},
+		},
+		AttestingIndices: []uint64{0, 1},
+	})
+	domain, err := signing.Domain(beaconState.Fork(), 0, params.BeaconConfig().DomainBeaconAttester, beaconState.GenesisValidatorsRoot())
+	require.NoError(t, err)
+	signingRoot, err := signing.ComputeSigningRoot(att1.Data, domain)
+	assert.NoError(t, err, "Could not get signing root of beacon block header")
+	sig0 := privKeys[0].Sign(signingRoot[:])
+	sig1 := privKeys[1].Sign(signingRoot[:])
+	aggregateSig := bls.AggregateSignatures([]bls.Signature{sig0, sig1})
+	att1.Signature = aggregateSig.Marshal()
+
+	att2 := util.HydrateIndexedAttestation(&ethpb.IndexedAttestation{
+		AttestingIndices: []uint64{0, 1},
+	})
+	signingRoot, err = signing.ComputeSigningRoot(att2.Data, domain)
+	assert.NoError(t, err, "Could not get signing root of beacon block header")
+	sig0 = privKeys[0].Sign(signingRoot[:])
+	sig1 = privKeys[1].Sign(signingRoot[:])
+	aggregateSig = bls.AggregateSignatures([]bls.Signature{sig0, sig1})
+	att2.Signature = aggregateSig.Marshal()
+
+	slashings := []*ethpb.AttesterSlashing{
+		{
+			Attestation_1: att1,
+			Attestation_2: att2,
+		},
+	}
+
+	currentSlot := 2 * params.BeaconConfig().SlotsPerEpoch
+	require.NoError(t, beaconState.SetSlot(currentSlot))
+
+	b := util.NewBeaconBlock()
+	b.Block = &ethpb.BeaconBlock{
+		Body: &ethpb.BeaconBlockBody{
+			AttesterSlashings: slashings,
+		},
+	}
+
+	newState, err := blocks.ProcessAttesterSlashings(context.Background(), beaconState, b.Block.Body.AttesterSlashings, v.SlashValidator)
+	require.NoError(t, err)
+	newRegistry := newState.Validators()
+
+	// Given the intersection of slashable indices is [1], only validator
+	// at index 1 should be slashed and exited. We confirm this below.
+	if newRegistry[1].ExitEpoch != beaconState.Validators()[1].ExitEpoch {
+		t.Errorf(
+			`
+			Expected validator at index 1's exit epoch to match
+			%d, received %d instead
+			`,
+			beaconState.Validators()[1].ExitEpoch,
+			newRegistry[1].ExitEpoch,
+		)
+	}
+
+	require.Equal(t, uint64(31000000000), newState.Balances()[1])
+	require.Equal(t, uint64(32000000000), newState.Balances()[2])
+}
--- a/beacon-chain/core/blocks/block_operations_fuzz_test.go
+++ b/beacon-chain/core/blocks/block_operations_fuzz_test.go
@@ -6,7 +6,7 @@ import (

 	fuzz "github.com/google/gofuzz"
 	v "github.com/prysmaticlabs/prysm/v3/beacon-chain/core/validators"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	"github.com/prysmaticlabs/prysm/v3/consensus-types/blocks"
@@ -24,7 +24,7 @@ func TestFuzzProcessAttestationNoVerify_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(att)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		_, err = ProcessAttestationNoVerifySignature(ctx, s, att)
 		_ = err
@@ -40,9 +40,9 @@ func TestFuzzProcessBlockHeader_10000(t *testing.T) {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(block)

-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
-		if block.Block == nil || block.Block.Body == nil {
+		if block.Block == nil || block.Block.Body == nil || block.Block.Body.Eth1Data == nil {
 			continue
 		}
 		wsb, err := blocks.NewSignedBeaconBlock(block)
@@ -79,7 +79,7 @@ func TestFuzzverifyDepositDataSigningRoot_10000(_ *testing.T) {
 func TestFuzzProcessEth1DataInBlock_10000(t *testing.T) {
 	fuzzer := fuzz.NewWithSeed(0)
 	e := &ethpb.Eth1Data{}
-	state, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
+	state, err := state_native.InitializeFromProtoUnsafePhase0(&ethpb.BeaconState{})
 	require.NoError(t, err)
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
@@ -111,7 +111,7 @@ func TestFuzzEth1DataHasEnoughSupport_10000(t *testing.T) {
 	for i := 0; i < 100000; i++ {
 		fuzzer.Fuzz(eth1data)
 		fuzzer.Fuzz(&stateVotes)
-		s, err := v1.InitializeFromProto(&ethpb.BeaconState{
+		s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 			Eth1DataVotes: stateVotes,
 		})
 		require.NoError(t, err)
@@ -129,7 +129,7 @@ func TestFuzzProcessBlockHeaderNoVerify_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(block)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		_, err = ProcessBlockHeaderNoVerify(context.Background(), s, block.Slot, block.ProposerIndex, block.ParentRoot, []byte{})
 		_ = err
@@ -144,7 +144,7 @@ func TestFuzzProcessRandao_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(b)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		if b.Block == nil || b.Block.Body == nil {
 			continue
@@ -166,7 +166,7 @@ func TestFuzzProcessRandaoNoVerify_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(blockBody)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessRandaoNoVerify(s, blockBody.RandaoReveal)
 		if err != nil && r != nil {
@@ -183,7 +183,7 @@ func TestFuzzProcessProposerSlashings_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(p)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessProposerSlashings(ctx, s, []*ethpb.ProposerSlashing{p}, v.SlashValidator)
 		if err != nil && r != nil {
@@ -199,7 +199,7 @@ func TestFuzzVerifyProposerSlashing_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(proposerSlashing)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		err = VerifyProposerSlashing(s, proposerSlashing)
 		_ = err
@@ -214,7 +214,7 @@ func TestFuzzProcessAttesterSlashings_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(a)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessAttesterSlashings(ctx, s, []*ethpb.AttesterSlashing{a}, v.SlashValidator)
 		if err != nil && r != nil {
@@ -231,7 +231,7 @@ func TestFuzzVerifyAttesterSlashing_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(attesterSlashing)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		err = VerifyAttesterSlashing(ctx, s, attesterSlashing)
 		_ = err
@@ -268,7 +268,7 @@ func TestFuzzProcessAttestationsNoVerify_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(b)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		if b.Block == nil || b.Block.Body == nil {
 			continue
@@ -290,7 +290,7 @@ func TestFuzzVerifyIndexedAttestationn_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(idxAttestation)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		err = VerifyIndexedAttestation(ctx, s, idxAttestation)
 		_ = err
@@ -305,7 +305,7 @@ func TestFuzzVerifyAttestation_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(attestation)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		err = VerifyAttestationSignature(ctx, s, attestation)
 		_ = err
@@ -322,7 +322,7 @@ func TestFuzzProcessDeposits_10000(t *testing.T) {
 		for i := range deposits {
 			fuzzer.Fuzz(deposits[i])
 		}
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessDeposits(ctx, s, deposits)
 		if err != nil && r != nil {
@@ -340,7 +340,7 @@ func TestFuzzProcessPreGenesisDeposit_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(deposit)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessPreGenesisDeposits(ctx, s, []*ethpb.Deposit{deposit})
 		if err != nil && r != nil {
@@ -357,7 +357,7 @@ func TestFuzzProcessDeposit_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(deposit)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, _, err := ProcessDeposit(s, deposit, true)
 		if err != nil && r != nil {
@@ -373,7 +373,7 @@ func TestFuzzverifyDeposit_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(deposit)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		err = verifyDeposit(s, deposit)
 		_ = err
@@ -388,7 +388,7 @@ func TestFuzzProcessVoluntaryExits_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(e)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessVoluntaryExits(ctx, s, []*ethpb.SignedVoluntaryExit{e})
 		if err != nil && r != nil {
@@ -404,7 +404,7 @@ func TestFuzzProcessVoluntaryExitsNoVerify_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(e)
-		s, err := v1.InitializeFromProtoUnsafe(state)
+		s, err := state_native.InitializeFromProtoUnsafePhase0(state)
 		require.NoError(t, err)
 		r, err := ProcessVoluntaryExits(context.Background(), s, []*ethpb.SignedVoluntaryExit{e})
 		if err != nil && r != nil {
@@ -425,7 +425,7 @@ func TestFuzzVerifyExit_10000(_ *testing.T) {
 		fuzzer.Fuzz(rawVal)
 		fuzzer.Fuzz(fork)
 		fuzzer.Fuzz(&slot)
-		val, err := v1.NewValidator(&ethpb.Validator{})
+		val, err := state_native.NewValidator(&ethpb.Validator{})
 		_ = err
 		err = VerifyExitAndSignature(val, slot, fork, ve, params.BeaconConfig().ZeroHash[:])
 		_ = err
--- a/beacon-chain/core/blocks/deposit.go
+++ b/beacon-chain/core/blocks/deposit.go
@@ -71,8 +71,9 @@ func ActivateValidatorWithEffectiveBalance(beaconState state.BeaconState, deposi
 // into the beacon chain.
 //
 // Spec pseudocode definition:
-//   For each deposit in block.body.deposits:
-//     process_deposit(state, deposit)
+//
+//	For each deposit in block.body.deposits:
+//	  process_deposit(state, deposit)
 func ProcessDeposits(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -120,40 +121,41 @@ func BatchVerifyDepositsSignatures(ctx context.Context, deposits []*ethpb.Deposi
 //
 // Spec pseudocode definition:
 // def process_deposit(state: BeaconState, deposit: Deposit) -> None:
-//    # Verify the Merkle branch
-//    assert is_valid_merkle_branch(
-//        leaf=hash_tree_root(deposit.data),
-//        branch=deposit.proof,
-//        depth=DEPOSIT_CONTRACT_TREE_DEPTH + 1,  # Add 1 for the List length mix-in
-//        index=state.eth1_deposit_index,
-//        root=state.eth1_data.deposit_root,
-//    )
 //
-//    # Deposits must be processed in order
-//    state.eth1_deposit_index += 1
+//	# Verify the Merkle branch
+//	assert is_valid_merkle_branch(
+//	    leaf=hash_tree_root(deposit.data),
+//	    branch=deposit.proof,
+//	    depth=DEPOSIT_CONTRACT_TREE_DEPTH + 1,  # Add 1 for the List length mix-in
+//	    index=state.eth1_deposit_index,
+//	    root=state.eth1_data.deposit_root,
+//	)
 //
-//    pubkey = deposit.data.pubkey
-//    amount = deposit.data.amount
-//    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
-//        deposit_message = DepositMessage(
-//            pubkey=deposit.data.pubkey,
-//            withdrawal_credentials=deposit.data.withdrawal_credentials,
-//            amount=deposit.data.amount,
-//        )
-//        domain = compute_domain(DOMAIN_DEPOSIT)  # Fork-agnostic domain since deposits are valid across forks
-//        signing_root = compute_signing_root(deposit_message, domain)
-//        if not bls.Verify(pubkey, signing_root, deposit.data.signature):
-//            return
+//	# Deposits must be processed in order
+//	state.eth1_deposit_index += 1
 //
-//        # Add validator and balance entries
-//        state.validators.append(get_validator_from_deposit(state, deposit))
-//        state.balances.append(amount)
-//    else:
-//        # Increase balance by deposit amount
-//        index = ValidatorIndex(validator_pubkeys.index(pubkey))
-//        increase_balance(state, index, amount)
+//	pubkey = deposit.data.pubkey
+//	amount = deposit.data.amount
+//	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
+//	    deposit_message = DepositMessage(
+//	        pubkey=deposit.data.pubkey,
+//	        withdrawal_credentials=deposit.data.withdrawal_credentials,
+//	        amount=deposit.data.amount,
+//	    )
+//	    domain = compute_domain(DOMAIN_DEPOSIT)  # Fork-agnostic domain since deposits are valid across forks
+//	    signing_root = compute_signing_root(deposit_message, domain)
+//	    if not bls.Verify(pubkey, signing_root, deposit.data.signature):
+//	        return
+//
+//	    # Add validator and balance entries
+//	    state.validators.append(get_validator_from_deposit(state, deposit))
+//	    state.balances.append(amount)
+//	else:
+//	    # Increase balance by deposit amount
+//	    index = ValidatorIndex(validator_pubkeys.index(pubkey))
+//	    increase_balance(state, index, amount)
 func ProcessDeposit(beaconState state.BeaconState, deposit *ethpb.Deposit, verifySignature bool) (state.BeaconState, bool, error) {
 	var newValidator bool
 	if err := verifyDeposit(beaconState, deposit); err != nil {
--- a/beacon-chain/core/blocks/deposit_test.go
+++ b/beacon-chain/core/blocks/deposit_test.go
@@ -6,7 +6,7 @@ import (

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	fieldparams "github.com/prysmaticlabs/prysm/v3/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
@@ -40,7 +40,7 @@ func TestProcessDeposits_SameValidatorMultipleDepositsSameBlock(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -80,7 +80,7 @@ func TestProcessDeposits_MerkleBranchFailsVerification(t *testing.T) {
 			Deposits: []*ethpb.Deposit{deposit},
 		},
 	}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Eth1Data: &ethpb.Eth1Data{
 			DepositRoot: []byte{0},
 			BlockHash:   []byte{1},
@@ -111,7 +111,7 @@ func TestProcessDeposits_AddsNewValidatorDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -175,7 +175,7 @@ func TestProcessDeposits_RepeatedDeposit_IncreasesValidatorBalance(t *testing.T)
 	balances := []uint64{0, 50}
 	root, err := depositTrie.HashTreeRoot()
 	require.NoError(t, err)
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data: &ethpb.Eth1Data{
@@ -203,7 +203,7 @@ func TestProcessDeposit_AddsNewValidatorDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -247,7 +247,7 @@ func TestProcessDeposit_SkipsInvalidDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -305,7 +305,7 @@ func TestPreGenesisDeposits_SkipInvalidDeposit(t *testing.T) {
 		},
 	}
 	balances := []uint64{0}
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data:   eth1Data,
@@ -383,7 +383,7 @@ func TestProcessDeposit_RepeatedDeposit_IncreasesValidatorBalance(t *testing.T)
 	root, err := depositTrie.HashTreeRoot()
 	require.NoError(t, err)

-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Balances:   balances,
 		Eth1Data: &ethpb.Eth1Data{
--- a/beacon-chain/core/blocks/error.go
+++ b/beacon-chain/core/blocks/error.go
@@ -6,3 +6,8 @@ var errNilSignedWithdrawalMessage = errors.New("nil SignedBLSToExecutionChange m
 var errNilWithdrawalMessage = errors.New("nil BLSToExecutionChange message")
 var errInvalidBLSPrefix = errors.New("withdrawal credential prefix is not a BLS prefix")
 var errInvalidWithdrawalCredentials = errors.New("withdrawal credentials do not match")
+var errInvalidWithdrawalIndex = errors.New("invalid withdrawal index")
+var errInvalidValidatorIndex = errors.New("invalid validator index")
+var errInvalidWithdrawalAmount = errors.New("invalid withdrawal amount")
+var errInvalidExecutionAddress = errors.New("invalid execution address")
+var errInvalidWithdrawalNumber = errors.New("invalid number of withdrawals")
--- a/beacon-chain/core/blocks/eth1_data.go
+++ b/beacon-chain/core/blocks/eth1_data.go
@@ -15,10 +15,11 @@ import (
 // into the beacon state.
 //
 // Official spec definition:
-//   def process_eth1_data(state: BeaconState, body: BeaconBlockBody) -> None:
-//    state.eth1_data_votes.append(body.eth1_data)
-//    if state.eth1_data_votes.count(body.eth1_data) * 2 > EPOCHS_PER_ETH1_VOTING_PERIOD * SLOTS_PER_EPOCH:
-//        state.eth1_data = body.eth1_data
+//
+//	def process_eth1_data(state: BeaconState, body: BeaconBlockBody) -> None:
+//	 state.eth1_data_votes.append(body.eth1_data)
+//	 if state.eth1_data_votes.count(body.eth1_data) * 2 > EPOCHS_PER_ETH1_VOTING_PERIOD * SLOTS_PER_EPOCH:
+//	     state.eth1_data = body.eth1_data
 func ProcessEth1DataInBlock(_ context.Context, beaconState state.BeaconState, eth1Data *ethpb.Eth1Data) (state.BeaconState, error) {
 	if beaconState == nil || beaconState.IsNil() {
 		return nil, errors.New("nil state")
--- a/beacon-chain/core/blocks/eth1_data_test.go
+++ b/beacon-chain/core/blocks/eth1_data_test.go
@@ -6,7 +6,7 @@ import (
 	"testing"

 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/blocks"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/encoding/bytesutil"
@@ -70,7 +70,7 @@ func TestEth1DataHasEnoughSupport(t *testing.T) {
 			c.EpochsPerEth1VotingPeriod = tt.votingPeriodLength
 			params.OverrideBeaconConfig(c)

-			s, err := v1.InitializeFromProto(&ethpb.BeaconState{
+			s, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 				Eth1DataVotes: tt.stateVotes,
 			})
 			require.NoError(t, err)
@@ -160,7 +160,7 @@ func TestAreEth1DataEqual(t *testing.T) {
 }

 func TestProcessEth1Data_SetsCorrectly(t *testing.T) {
-	beaconState, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	beaconState, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Eth1DataVotes: []*ethpb.Eth1Data{},
 	})
 	require.NoError(t, err)
--- a/beacon-chain/core/blocks/exit.go
+++ b/beacon-chain/core/blocks/exit.go
@@ -27,23 +27,24 @@ var ValidatorCannotExitYetMsg = "validator has not been active long enough to ex
 // should exit the state's validator registry.
 //
 // Spec pseudocode definition:
-//   def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
-//    voluntary_exit = signed_voluntary_exit.message
-//    validator = state.validators[voluntary_exit.validator_index]
-//    # Verify the validator is active
-//    assert is_active_validator(validator, get_current_epoch(state))
-//    # Verify exit has not been initiated
-//    assert validator.exit_epoch == FAR_FUTURE_EPOCH
-//    # Exits must specify an epoch when they become valid; they are not valid before then
-//    assert get_current_epoch(state) >= voluntary_exit.epoch
-//    # Verify the validator has been active long enough
-//    assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
-//    # Verify signature
-//    domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
-//    signing_root = compute_signing_root(voluntary_exit, domain)
-//    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
-//    # Initiate exit
-//    initiate_validator_exit(state, voluntary_exit.validator_index)
+//
+//	def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
+//	 voluntary_exit = signed_voluntary_exit.message
+//	 validator = state.validators[voluntary_exit.validator_index]
+//	 # Verify the validator is active
+//	 assert is_active_validator(validator, get_current_epoch(state))
+//	 # Verify exit has not been initiated
+//	 assert validator.exit_epoch == FAR_FUTURE_EPOCH
+//	 # Exits must specify an epoch when they become valid; they are not valid before then
+//	 assert get_current_epoch(state) >= voluntary_exit.epoch
+//	 # Verify the validator has been active long enough
+//	 assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
+//	 # Verify signature
+//	 domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
+//	 signing_root = compute_signing_root(voluntary_exit, domain)
+//	 assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
+//	 # Initiate exit
+//	 initiate_validator_exit(state, voluntary_exit.validator_index)
 func ProcessVoluntaryExits(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -71,23 +72,24 @@ func ProcessVoluntaryExits(
 // VerifyExitAndSignature implements the spec defined validation for voluntary exits.
 //
 // Spec pseudocode definition:
-//   def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
-//    voluntary_exit = signed_voluntary_exit.message
-//    validator = state.validators[voluntary_exit.validator_index]
-//    # Verify the validator is active
-//    assert is_active_validator(validator, get_current_epoch(state))
-//    # Verify exit has not been initiated
-//    assert validator.exit_epoch == FAR_FUTURE_EPOCH
-//    # Exits must specify an epoch when they become valid; they are not valid before then
-//    assert get_current_epoch(state) >= voluntary_exit.epoch
-//    # Verify the validator has been active long enough
-//    assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
-//    # Verify signature
-//    domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
-//    signing_root = compute_signing_root(voluntary_exit, domain)
-//    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
-//    # Initiate exit
-//    initiate_validator_exit(state, voluntary_exit.validator_index)
+//
+//	def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
+//	 voluntary_exit = signed_voluntary_exit.message
+//	 validator = state.validators[voluntary_exit.validator_index]
+//	 # Verify the validator is active
+//	 assert is_active_validator(validator, get_current_epoch(state))
+//	 # Verify exit has not been initiated
+//	 assert validator.exit_epoch == FAR_FUTURE_EPOCH
+//	 # Exits must specify an epoch when they become valid; they are not valid before then
+//	 assert get_current_epoch(state) >= voluntary_exit.epoch
+//	 # Verify the validator has been active long enough
+//	 assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
+//	 # Verify signature
+//	 domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
+//	 signing_root = compute_signing_root(voluntary_exit, domain)
+//	 assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
+//	 # Initiate exit
+//	 initiate_validator_exit(state, voluntary_exit.validator_index)
 func VerifyExitAndSignature(
 	validator state.ReadOnlyValidator,
 	currentSlot types.Slot,
@@ -117,23 +119,24 @@ func VerifyExitAndSignature(
 // verifyExitConditions implements the spec defined validation for voluntary exits(excluding signatures).
 //
 // Spec pseudocode definition:
-//   def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
-//    voluntary_exit = signed_voluntary_exit.message
-//    validator = state.validators[voluntary_exit.validator_index]
-//    # Verify the validator is active
-//    assert is_active_validator(validator, get_current_epoch(state))
-//    # Verify exit has not been initiated
-//    assert validator.exit_epoch == FAR_FUTURE_EPOCH
-//    # Exits must specify an epoch when they become valid; they are not valid before then
-//    assert get_current_epoch(state) >= voluntary_exit.epoch
-//    # Verify the validator has been active long enough
-//    assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
-//    # Verify signature
-//    domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
-//    signing_root = compute_signing_root(voluntary_exit, domain)
-//    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
-//    # Initiate exit
-//    initiate_validator_exit(state, voluntary_exit.validator_index)
+//
+//	def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
+//	 voluntary_exit = signed_voluntary_exit.message
+//	 validator = state.validators[voluntary_exit.validator_index]
+//	 # Verify the validator is active
+//	 assert is_active_validator(validator, get_current_epoch(state))
+//	 # Verify exit has not been initiated
+//	 assert validator.exit_epoch == FAR_FUTURE_EPOCH
+//	 # Exits must specify an epoch when they become valid; they are not valid before then
+//	 assert get_current_epoch(state) >= voluntary_exit.epoch
+//	 # Verify the validator has been active long enough
+//	 assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
+//	 # Verify signature
+//	 domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
+//	 signing_root = compute_signing_root(voluntary_exit, domain)
+//	 assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
+//	 # Initiate exit
+//	 initiate_validator_exit(state, voluntary_exit.validator_index)
 func verifyExitConditions(validator state.ReadOnlyValidator, currentSlot types.Slot, exit *ethpb.VoluntaryExit) error {
 	currentEpoch := slots.ToEpoch(currentSlot)
 	// Verify the validator is active.
--- a/beacon-chain/core/blocks/exit_test.go
+++ b/beacon-chain/core/blocks/exit_test.go
@@ -8,7 +8,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/signing"
 	"github.com/prysmaticlabs/prysm/v3/beacon-chain/core/time"
-	v1 "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/v1"
+	state_native "github.com/prysmaticlabs/prysm/v3/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v3/config/params"
 	types "github.com/prysmaticlabs/prysm/v3/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v3/crypto/bls"
@@ -32,7 +32,7 @@ func TestProcessVoluntaryExits_NotActiveLongEnoughToExit(t *testing.T) {
 			ExitEpoch: params.BeaconConfig().FarFutureEpoch,
 		},
 	}
-	state, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	state, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Slot:       10,
 	})
@@ -62,7 +62,7 @@ func TestProcessVoluntaryExits_ExitAlreadySubmitted(t *testing.T) {
 			ExitEpoch: 10,
 		},
 	}
-	state, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	state, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Slot:       0,
 	})
@@ -94,7 +94,7 @@ func TestProcessVoluntaryExits_AppliesCorrectStatus(t *testing.T) {
 			ActivationEpoch: 0,
 		},
 	}
-	state, err := v1.InitializeFromProto(&ethpb.BeaconState{
+	state, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Validators: registry,
 		Fork: &ethpb.Fork{
 			CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
--- a/beacon-chain/core/blocks/exports_test.go
+++ b/beacon-chain/core/blocks/exports_test.go
@@ -0,0 +1,3 @@
+package blocks
+
+var ProcessBLSToExecutionChange = processBLSToExecutionChange
--- a/beacon-chain/core/blocks/header.go
+++ b/beacon-chain/core/blocks/header.go
@@ -18,27 +18,27 @@ import (
 //
 // Spec pseudocode definition:
 //
-//  def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
-//    # Verify that the slots match
-//    assert block.slot == state.slot
-//    # Verify that the block is newer than latest block header
-//    assert block.slot > state.latest_block_header.slot
-//    # Verify that proposer index is the correct index
-//    assert block.proposer_index == get_beacon_proposer_index(state)
-//    # Verify that the parent matches
-//    assert block.parent_root == hash_tree_root(state.latest_block_header)
-//    # Cache current block as the new latest block
-//    state.latest_block_header = BeaconBlockHeader(
-//        slot=block.slot,
-//        proposer_index=block.proposer_index,
-//        parent_root=block.parent_root,
-//        state_root=Bytes32(),  # Overwritten in the next process_slot call
-//        body_root=hash_tree_root(block.body),
-//    )
+//	def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
+//	  # Verify that the slots match
+//	  assert block.slot == state.slot
+//	  # Verify that the block is newer than latest block header
+//	  assert block.slot > state.latest_block_header.slot
+//	  # Verify that proposer index is the correct index
+//	  assert block.proposer_index == get_beacon_proposer_index(state)
+//	  # Verify that the parent matches
+//	  assert block.parent_root == hash_tree_root(state.latest_block_header)
+//	  # Cache current block as the new latest block
+//	  state.latest_block_header = BeaconBlockHeader(
+//	      slot=block.slot,
+//	      proposer_index=block.proposer_index,
+//	      parent_root=block.parent_root,
+//	      state_root=Bytes32(),  # Overwritten in the next process_slot call
+//	      body_root=hash_tree_root(block.body),
+//	  )
 //
-//    # Verify proposer is not slashed
-//    proposer = state.validators[block.proposer_index]
-//    assert not proposer.slashed
+//	  # Verify proposer is not slashed
+//	  proposer = state.validators[block.proposer_index]
+//	  assert not proposer.slashed
 func ProcessBlockHeader(
 	ctx context.Context,
 	beaconState state.BeaconState,
@@ -51,13 +51,15 @@ func ProcessBlockHeader(
 	if err != nil {
 		return nil, err
 	}
-	beaconState, err = ProcessBlockHeaderNoVerify(ctx, beaconState, block.Block().Slot(), block.Block().ProposerIndex(), block.Block().ParentRoot(), bodyRoot[:])
+	parentRoot := block.Block().ParentRoot()
+	beaconState, err = ProcessBlockHeaderNoVerify(ctx, beaconState, block.Block().Slot(), block.Block().ProposerIndex(), parentRoot[:], bodyRoot[:])
 	if err != nil {
 		return nil, err
 	}

 	// Verify proposer signature.
-	if err := VerifyBlockSignature(beaconState, block.Block().ProposerIndex(), block.Signature(), block.Block().HashTreeRoot); err != nil {
+	sig := block.Signature()
+	if err := VerifyBlockSignature(beaconState, block.Block().ProposerIndex(), sig[:], block.Block().HashTreeRoot); err != nil {
 		return nil, err
 	}

@@ -71,27 +73,28 @@ func ProcessBlockHeader(
 // using a unsigned block.
 //
 // Spec pseudocode definition:
-//  def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
-//    # Verify that the slots match
-//    assert block.slot == state.slot
-//    # Verify that the block is newer than latest block header
-//    assert block.slot > state.latest_block_header.slot
-//    # Verify that proposer index is the correct index
-//    assert block.proposer_index == get_beacon_proposer_index(state)
-//    # Verify that the parent matches
-//    assert block.parent_root == hash_tree_root(state.latest_block_header)
-//    # Cache current block as the new latest block
-//    state.latest_block_header = BeaconBlockHeader(
-//        slot=block.slot,
-//        proposer_index=block.proposer_index,
-//        parent_root=block.parent_root,
-//        state_root=Bytes32(),  # Overwritten in the next process_slot call
-//        body_root=hash_tree_root(block.body),
-//    )
 //
-//    # Verify proposer is not slashed
-//    proposer = state.validators[block.proposer_index]
-//    assert not proposer.slashed
+//	def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
+//	  # Verify that the slots match
+//	  assert block.slot == state.slot
+//	  # Verify that the block is newer than latest block header
+//	  assert block.slot > state.latest_block_header.slot
+//	  # Verify that proposer index is the correct index
+//	  assert block.proposer_index == get_beacon_proposer_index(state)
+//	  # Verify that the parent matches
+//	  assert block.parent_root == hash_tree_root(state.latest_block_header)
+//	  # Cache current block as the new latest block
+//	  state.latest_block_header = BeaconBlockHeader(
+//	      slot=block.slot,
+//	      proposer_index=block.proposer_index,
+//	      parent_root=block.parent_root,
+//	      state_root=Bytes32(),  # Overwritten in the next process_slot call
+//	      body_root=hash_tree_root(block.body),
+//	  )
+//
+//	  # Verify proposer is not slashed
+//	  proposer = state.validators[block.proposer_index]
+//	  assert not proposer.slashed
 func ProcessBlockHeaderNoVerify(
 	ctx context.Context,
 	beaconState state.BeaconState,
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .0.0
 .3.0