diff --git a/test/LegacyCollectTest.t.sol b/test/LegacyCollectTest.t.sol
index 961656b..37824db 100644
--- a/test/LegacyCollectTest.t.sol
+++ b/test/LegacyCollectTest.t.sol
@@ -98,6 +98,51 @@ contract LegacyCollectTest is BaseTest, ReferralSystemTest {
         _collect(defaultAccount.ownerPk, defaultCollectParams);
     }
 
+    function testCannotExecuteOperationIf_ReferralProfileIdsPassedQty_DiffersFromPubIdsQty() public override {
+        // ReferralSystem inherited test that does not apply to this file.
+    }
+
+    function testCannotPass_TargetedPublication_AsReferrer() public override {
+        // Note: The following publication is converted to Legacy V1 in this test's setUp.
+        TestPublication memory targetPub = TestPublication(defaultAccount.profileId, pubId);
+
+        _referralSystem_PrepareOperation(
+            targetPub,
+            _toUint256Array(targetPub.profileId),
+            _toUint256Array(targetPub.pubId)
+        );
+        vm.expectRevert(Errors.InvalidReferrer.selector);
+        _referralSystem_ExecutePreparedOperation();
+    }
+
+    function testCannotPass_UnexistentProfile_AsReferrer(uint256 unexistentProfileId, uint8 anyPubId) public override {
+        // Note: The following publication is converted to Legacy V1 in this test's setUp.
+        TestPublication memory targetPub = TestPublication(defaultAccount.profileId, pubId);
+
+        vm.assume(!hub.exists(unexistentProfileId));
+        vm.assume(anyPubId != 0);
+        _referralSystem_PrepareOperation(targetPub, _toUint256Array(unexistentProfileId), _toUint256Array(anyPubId));
+        vm.expectRevert(Errors.InvalidReferrer.selector);
+        _referralSystem_ExecutePreparedOperation();
+    }
+
+    function testCannotPass_UnexistentPublication_AsReferrer(uint256 unexistentPubId) public override {
+        // Note: The following publication is converted to Legacy V1 in this test's setUp.
+        TestPublication memory targetPub = TestPublication(defaultAccount.profileId, pubId);
+
+        TestPublication memory pub = _comment(targetPub);
+        uint256 existentProfileId = pub.profileId;
+        vm.assume(unexistentPubId > pub.pubId);
+
+        _referralSystem_PrepareOperation(
+            targetPub,
+            _toUint256Array(existentProfileId),
+            _toUint256Array(unexistentPubId)
+        );
+        vm.expectRevert(Errors.InvalidReferrer.selector);
+        _referralSystem_ExecutePreparedOperation();
+    }
+
     function testCollect() public {
         Types.Publication memory pub = hub.getPublication(defaultAccount.profileId, pubId);
         assertTrue(pub.__DEPRECATED__collectNFT == address(0));
@@ -218,8 +263,8 @@ contract LegacyCollectTest is BaseTest, ReferralSystemTest {
 
     function _referralSystem_ExpectRevertsIfNeeded(
         TestPublication memory target,
-        uint256[] memory referrerProfileIds,
-        uint256[] memory referrerPubIds
+        uint256[] memory /* referrerProfileIds */,
+        uint256[] memory /* referrerPubIds */
     ) internal virtual override returns (bool) {
         if (skipTest) {
             return true;
@@ -267,16 +312,16 @@ contract LegacyCollectTest is BaseTest, ReferralSystemTest {
     }
 
     function _referralSystem_ExecutePreparedOperation() internal virtual override {
-        console.log(
-            'LEGACY COLLECTING: (%s, %s)',
-            defaultCollectParams.publicationCollectedProfileId,
-            defaultCollectParams.publicationCollectedId
-        );
-        console.log(
-            '    with referrer: (%s, %s)',
-            defaultCollectParams.referrerProfileId,
-            defaultCollectParams.referrerPubId
-        );
+        // console.log(
+        //     'LEGACY COLLECTING: (%s, %s)',
+        //     defaultCollectParams.publicationCollectedProfileId,
+        //     defaultCollectParams.publicationCollectedId
+        // );
+        // console.log(
+        //     '    with referrer: (%s, %s)',
+        //     defaultCollectParams.referrerProfileId,
+        //     defaultCollectParams.referrerPubId
+        // );
         if (skipTest) {
             console.log('   ^^^ SKIPPED ^^^');
             return;
diff --git a/test/ReferralSystem.t.sol b/test/ReferralSystem.t.sol
index 3d5f35c..be9baba 100644
--- a/test/ReferralSystem.t.sol
+++ b/test/ReferralSystem.t.sol
@@ -122,11 +122,11 @@ abstract contract ReferralSystemTest is BaseTest {
                 for (uint256 i = 0; i < treeV2.references.length; i++) {
                     TestPublication memory target = treeV2.references[i];
                     for (uint256 j = 0; j < treeV2.references.length; j++) {
-                        TestPublication memory referralPub = treeV2.references[j];
+                        TestPublication memory quoteOrCommentAsReferralPub = treeV2.references[j];
                         if (i == j) continue; // skip self
                         // vm.expectCall /* */();
 
-                        _executeOperation(target, referralPub);
+                        _executeOperation(target, quoteOrCommentAsReferralPub);
                     }
 
                     // One special case is a post as referal for reference node
@@ -166,7 +166,6 @@ abstract contract ReferralSystemTest is BaseTest {
 
     function testV1_TargetPost_ReferralMirror(uint256 v1FuzzBitmap) public virtual {
         vm.assume(v1FuzzBitmap < 2 ** 11);
-        uint256 commentQuoteFuzzBitmap = 0;
         Tree memory treeV1 = _createV1Tree(v1FuzzBitmap);
 
         // Target a post with mirrors as referrals
@@ -186,9 +185,6 @@ abstract contract ReferralSystemTest is BaseTest {
         for (uint256 i = 0; i < treeV1.references.length; i++) {
             TestPublication memory target = treeV1.references[i];
 
-            // check if target is V2 or V1
-            Types.Publication memory targetPublication = hub.getPublication(target.profileId, target.pubId);
-
             _referralSystem_PrepareOperation(target, referralPub);
 
             // Shoule revert as V1-contaminated trees don't have a root and only allow downwards referrals
@@ -475,7 +471,7 @@ abstract contract ReferralSystemTest is BaseTest {
         return TestPublication(publisher.profileId, pubId);
     }
 
-    function testCannotExecuteOperationIf_ReferralProfileIdsPassedQty_DiffersFromPubIdsQty() public {
+    function testCannotExecuteOperationIf_ReferralProfileIdsPassedQty_DiffersFromPubIdsQty() public virtual {
         Types.PostParams memory postParams = _getDefaultPostParams();
         postParams.referenceModule = address(mockReferenceModule);
         postParams.referenceModuleInitData = abi.encode(true);
@@ -493,7 +489,7 @@ abstract contract ReferralSystemTest is BaseTest {
         _referralSystem_ExecutePreparedOperation();
     }
 
-    function testCannotPass_TargetedPublication_AsReferrer() public {
+    function testCannotPass_TargetedPublication_AsReferrer() public virtual {
         Types.PostParams memory postParams = _getDefaultPostParams();
         postParams.referenceModule = address(mockReferenceModule);
         postParams.referenceModuleInitData = abi.encode(true);
@@ -505,7 +501,7 @@ abstract contract ReferralSystemTest is BaseTest {
         _referralSystem_ExecutePreparedOperation();
     }
 
-    function testCannotPass_UnexistentProfile_AsReferrer(uint256 unexistentProfileId, uint8 pubId) public {
+    function testCannotPass_UnexistentProfile_AsReferrer(uint256 unexistentProfileId, uint8 pubId) public virtual {
         Types.PostParams memory postParams = _getDefaultPostParams();
         postParams.referenceModule = address(mockReferenceModule);
         postParams.referenceModuleInitData = abi.encode(true);
@@ -519,7 +515,7 @@ abstract contract ReferralSystemTest is BaseTest {
         _referralSystem_ExecutePreparedOperation();
     }
 
-    function testCannotPass_UnexistentPublication_AsReferrer(uint256 unexistentPubId) public {
+    function testCannotPass_UnexistentPublication_AsReferrer(uint256 unexistentPubId) public virtual {
         Types.PostParams memory postParams = _getDefaultPostParams();
         postParams.referenceModule = address(mockReferenceModule);
         postParams.referenceModuleInitData = abi.encode(true);