diff --git a/cmd/utils/cmd.go b/cmd/utils/cmd.go
index fc66e11dca..791b3d1d20 100644
--- a/cmd/utils/cmd.go
+++ b/cmd/utils/cmd.go
@@ -262,7 +262,6 @@ func ImportHistory(chain *core.BlockChain, db ethdb.Database, dir string, networ
 		start    = time.Now()
 		reported = time.Now()
 		imported = 0
-		forker   = core.NewForkChoice(chain, nil)
 		h        = sha256.New()
 		buf      = bytes.NewBuffer(nil)
 	)
@@ -305,7 +304,7 @@ func ImportHistory(chain *core.BlockChain, db ethdb.Database, dir string, networ
 				if err != nil {
 					return fmt.Errorf("error reading receipts %d: %w", it.Number(), err)
 				}
-				if status, err := chain.HeaderChain().InsertHeaderChain([]*types.Header{block.Header()}, start, forker); err != nil {
+				if status, err := chain.HeaderChain().InsertHeaderChain([]*types.Header{block.Header()}, start); err != nil {
 					return fmt.Errorf("error inserting header %d: %w", it.Number(), err)
 				} else if status != core.CanonStatTy {
 					return fmt.Errorf("error inserting header %d, not canon: %v", it.Number(), status)
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index 611189a2cc..f55c3b52d0 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -2210,7 +2210,7 @@ func MakeChain(ctx *cli.Context, stack *node.Node, readonly bool) (*core.BlockCh
 		}
 	}
 	// Disable transaction indexing/unindexing by default.
-	chain, err := core.NewBlockChain(chainDb, cache, gspec, nil, engine, vmcfg, nil, nil)
+	chain, err := core.NewBlockChain(chainDb, cache, gspec, nil, engine, vmcfg, nil)
 	if err != nil {
 		Fatalf("Can't create BlockChain: %v", err)
 	}
diff --git a/cmd/utils/history_test.go b/cmd/utils/history_test.go
index a631eaf490..1074a358ec 100644
--- a/cmd/utils/history_test.go
+++ b/cmd/utils/history_test.go
@@ -78,7 +78,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 	})
 
 	// Initialize BlockChain.
-	chain, err := core.NewBlockChain(db, nil, genesis, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, nil, genesis, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("unable to initialize chain: %v", err)
 	}
@@ -171,7 +171,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 	})
 
 	genesis.MustCommit(db2, triedb.NewDatabase(db, triedb.HashDefaults))
-	imported, err := core.NewBlockChain(db2, nil, genesis, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	imported, err := core.NewBlockChain(db2, nil, genesis, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("unable to initialize chain: %v", err)
 	}
diff --git a/consensus/clique/clique_test.go b/consensus/clique/clique_test.go
index f14c8cb5ba..bacd207493 100644
--- a/consensus/clique/clique_test.go
+++ b/consensus/clique/clique_test.go
@@ -55,7 +55,7 @@ func TestReimportMirroredState(t *testing.T) {
 	copy(genspec.ExtraData[extraVanity:], addr[:])
 
 	// Generate a batch of blocks, each properly signed
-	chain, _ := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, genspec, nil, engine, vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, genspec, nil, engine, vm.Config{}, nil)
 	defer chain.Stop()
 
 	_, blocks, _ := core.GenerateChainWithGenesis(genspec, engine, 3, func(i int, block *core.BlockGen) {
@@ -87,7 +87,7 @@ func TestReimportMirroredState(t *testing.T) {
 	}
 	// Insert the first two blocks and make sure the chain is valid
 	db = rawdb.NewMemoryDatabase()
-	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil, nil)
+	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil)
 	defer chain.Stop()
 
 	if _, err := chain.InsertChain(blocks[:2]); err != nil {
@@ -100,7 +100,7 @@ func TestReimportMirroredState(t *testing.T) {
 	// Simulate a crash by creating a new chain on top of the database, without
 	// flushing the dirty states out. Insert the last block, triggering a sidechain
 	// reimport.
-	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil, nil)
+	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil)
 	defer chain.Stop()
 
 	if _, err := chain.InsertChain(blocks[2:]); err != nil {
diff --git a/consensus/clique/snapshot_test.go b/consensus/clique/snapshot_test.go
index 4ef7a7b3ae..6c46d1db4f 100644
--- a/consensus/clique/snapshot_test.go
+++ b/consensus/clique/snapshot_test.go
@@ -458,7 +458,7 @@ func (tt *cliqueTest) run(t *testing.T) {
 		batches[len(batches)-1] = append(batches[len(batches)-1], block)
 	}
 	// Pass all the headers through clique and ensure tallying succeeds
-	chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create test chain: %v", err)
 	}
diff --git a/core/bench_test.go b/core/bench_test.go
index 97713868a5..639d36e9ae 100644
--- a/core/bench_test.go
+++ b/core/bench_test.go
@@ -195,7 +195,7 @@ func benchInsertChain(b *testing.B, disk bool, gen func(int, *BlockGen)) {
 
 	// Time the insertion of the new chain.
 	// State and blocks are stored in the same DB.
-	chainman, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chainman, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer chainman.Stop()
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -312,7 +312,7 @@ func benchReadChain(b *testing.B, full bool, count uint64) {
 		if err != nil {
 			b.Fatalf("error opening database at %v: %v", dir, err)
 		}
-		chain, err := NewBlockChain(db, &cacheConfig, genesis, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(db, &cacheConfig, genesis, nil, ethash.NewFaker(), vm.Config{}, nil)
 		if err != nil {
 			b.Fatalf("error creating chain: %v", err)
 		}
diff --git a/core/block_validator_test.go b/core/block_validator_test.go
index c573ef91fa..16824467c1 100644
--- a/core/block_validator_test.go
+++ b/core/block_validator_test.go
@@ -50,7 +50,7 @@ func testHeaderVerification(t *testing.T, scheme string) {
 		headers[i] = block.Header()
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer chain.Stop()
 
 	for i := 0; i < len(blocks); i++ {
@@ -160,7 +160,7 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 		postHeaders[i] = block.Header()
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
 	defer chain.Stop()
 
 	// Verify the blocks before the merging
diff --git a/core/blockchain.go b/core/blockchain.go
index 397d917d73..b0c8da98ff 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -259,7 +259,6 @@ type BlockChain struct {
 	validator  Validator // Block and state validator interface
 	prefetcher Prefetcher
 	processor  Processor // Block transaction processor interface
-	forker     *ForkChoice
 	vmConfig   vm.Config
 	logger     *tracing.Hooks
 }
@@ -267,7 +266,7 @@ type BlockChain struct {
 // NewBlockChain returns a fully initialised block chain using information
 // available in the database. It initialises the default Ethereum Validator
 // and Processor.
-func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis, overrides *ChainOverrides, engine consensus.Engine, vmConfig vm.Config, shouldPreserve func(header *types.Header) bool, txLookupLimit *uint64) (*BlockChain, error) {
+func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis, overrides *ChainOverrides, engine consensus.Engine, vmConfig vm.Config, txLookupLimit *uint64) (*BlockChain, error) {
 	if cacheConfig == nil {
 		cacheConfig = defaultCacheConfig
 	}
@@ -312,7 +311,6 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis
 		return nil, err
 	}
 	bc.flushInterval.Store(int64(cacheConfig.TrieTimeLimit))
-	bc.forker = NewForkChoice(bc, shouldPreserve)
 	bc.stateCache = state.NewDatabaseWithNodeDB(bc.db, bc.triedb)
 	bc.validator = NewBlockValidator(chainConfig, bc)
 	bc.prefetcher = newStatePrefetcher(chainConfig, bc.hc)
@@ -1243,13 +1241,6 @@ func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain [
 
 		// Rewind may have occurred, skip in that case.
 		if bc.CurrentHeader().Number.Cmp(head.Number()) >= 0 {
-			reorg, err := bc.forker.ReorgNeeded(bc.CurrentSnapBlock(), head.Header())
-			if err != nil {
-				log.Warn("Reorg failed", "err", err)
-				return false
-			} else if !reorg {
-				return false
-			}
 			rawdb.WriteHeadFastBlockHash(bc.db, head.Hash())
 			bc.currentSnapBlock.Store(head.Header())
 			headFastBlockGauge.Update(int64(head.NumberU64()))
@@ -1548,42 +1539,30 @@ func (bc *BlockChain) writeBlockAndSetHead(block *types.Block, receipts []*types
 		return NonStatTy, err
 	}
 	currentBlock := bc.CurrentBlock()
-	reorg, err := bc.forker.ReorgNeeded(currentBlock, block.Header())
-	if err != nil {
-		return NonStatTy, err
-	}
-	if reorg {
-		// Reorganise the chain if the parent is not the head block
-		if block.ParentHash() != currentBlock.Hash() {
-			if err := bc.reorg(currentBlock, block); err != nil {
-				return NonStatTy, err
-			}
+
+	// Reorganise the chain if the parent is not the head block
+	if block.ParentHash() != currentBlock.Hash() {
+		if err := bc.reorg(currentBlock, block); err != nil {
+			return NonStatTy, err
 		}
-		status = CanonStatTy
-	} else {
-		status = SideStatTy
 	}
+
 	// Set new head.
-	if status == CanonStatTy {
-		bc.writeHeadBlock(block)
-	}
-	if status == CanonStatTy {
-		bc.chainFeed.Send(ChainEvent{Block: block, Hash: block.Hash(), Logs: logs})
-		if len(logs) > 0 {
-			bc.logsFeed.Send(logs)
-		}
-		// In theory, we should fire a ChainHeadEvent when we inject
-		// a canonical block, but sometimes we can insert a batch of
-		// canonical blocks. Avoid firing too many ChainHeadEvents,
-		// we will fire an accumulated ChainHeadEvent and disable fire
-		// event here.
-		if emitHeadEvent {
-			bc.chainHeadFeed.Send(ChainHeadEvent{Block: block})
-		}
-	} else {
-		bc.chainSideFeed.Send(ChainSideEvent{Block: block})
+	bc.writeHeadBlock(block)
+
+	bc.chainFeed.Send(ChainEvent{Block: block, Hash: block.Hash(), Logs: logs})
+	if len(logs) > 0 {
+		bc.logsFeed.Send(logs)
 	}
-	return status, nil
+	// In theory, we should fire a ChainHeadEvent when we inject
+	// a canonical block, but sometimes we can insert a batch of
+	// canonical blocks. Avoid firing too many ChainHeadEvents,
+	// we will fire an accumulated ChainHeadEvent and disable fire
+	// event here.
+	if emitHeadEvent {
+		bc.chainHeadFeed.Send(ChainHeadEvent{Block: block})
+	}
+	return CanonStatTy, nil
 }
 
 // InsertChain attempts to insert the given batch of blocks in to the canonical
@@ -1634,7 +1613,6 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 	if bc.insertStopped() {
 		return 0, nil
 	}
-
 	// Start a parallel signature recovery (signer will fluke on fork transition, minimal perf loss)
 	SenderCacher.RecoverFromBlocks(types.MakeSigner(bc.chainConfig, chain[0].Number(), chain[0].Time()), chain)
 
@@ -1667,24 +1645,10 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		//   2. The block is stored as a sidechain, and is lying about it's stateroot, and passes a stateroot
 		//      from the canonical chain, which has not been verified.
 		// Skip all known blocks that are behind us.
-		var (
-			reorg   bool
-			current = bc.CurrentBlock()
-		)
+		current := bc.CurrentBlock()
 		for block != nil && bc.skipBlock(err, it) {
-			reorg, err = bc.forker.ReorgNeeded(current, block.Header())
-			if err != nil {
-				return it.index, err
-			}
-			if reorg {
-				// Switch to import mode if the forker says the reorg is necessary
-				// and also the block is not on the canonical chain.
-				// In eth2 the forker always returns true for reorg decision (blindly trusting
-				// the external consensus engine), but in order to prevent the unnecessary
-				// reorgs when importing known blocks, the special case is handled here.
-				if block.NumberU64() > current.Number.Uint64() || bc.GetCanonicalHash(block.NumberU64()) != block.Hash() {
-					break
-				}
+			if block.NumberU64() > current.Number.Uint64() || bc.GetCanonicalHash(block.NumberU64()) != block.Hash() {
+				break
 			}
 			log.Debug("Ignoring already known block", "number", block.Number(), "hash", block.Hash())
 			stats.ignored++
@@ -2006,9 +1970,8 @@ func (bc *BlockChain) processBlock(block *types.Block, statedb *state.StateDB, s
 // insertSideChain is only used pre-merge.
 func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (int, error) {
 	var (
-		externTd  *big.Int
-		lastBlock = block
-		current   = bc.CurrentBlock()
+		externTd *big.Int
+		current  = bc.CurrentBlock()
 	)
 	// The first sidechain block error is already verified to be ErrPrunedAncestor.
 	// Since we don't import them here, we expect ErrUnknownAncestor for the remaining
@@ -2059,22 +2022,6 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 				"txs", len(block.Transactions()), "gas", block.GasUsed(), "uncles", len(block.Uncles()),
 				"root", block.Root())
 		}
-		lastBlock = block
-	}
-	// At this point, we've written all sidechain blocks to database. Loop ended
-	// either on some other error or all were processed. If there was some other
-	// error, we can ignore the rest of those blocks.
-	//
-	// If the externTd was larger than our local TD, we now need to reimport the previous
-	// blocks to regenerate the required state
-	reorg, err := bc.forker.ReorgNeeded(current, lastBlock.Header())
-	if err != nil {
-		return it.index, err
-	}
-	if !reorg {
-		localTd := bc.GetTd(current.Hash(), current.Number.Uint64())
-		log.Info("Sidechain written to disk", "start", it.first().NumberU64(), "end", it.previous().Number, "sidetd", externTd, "localtd", localTd)
-		return it.index, err
 	}
 	// Gather all the sidechain hashes (full blocks may be memory heavy)
 	var (
@@ -2541,7 +2488,7 @@ func (bc *BlockChain) InsertHeaderChain(chain []*types.Header) (int, error) {
 		return 0, errChainStopped
 	}
 	defer bc.chainmu.Unlock()
-	_, err := bc.hc.InsertHeaderChain(chain, start, bc.forker)
+	_, err := bc.hc.InsertHeaderChain(chain, start)
 	return 0, err
 }
 
diff --git a/core/blockchain_insert.go b/core/blockchain_insert.go
index 49e913aada..ec3f771818 100644
--- a/core/blockchain_insert.go
+++ b/core/blockchain_insert.go
@@ -170,11 +170,6 @@ func (it *insertIterator) current() *types.Header {
 	return it.chain[it.index].Header()
 }
 
-// first returns the first block in it.
-func (it *insertIterator) first() *types.Block {
-	return it.chain[0]
-}
-
 // remaining returns the number of remaining blocks.
 func (it *insertIterator) remaining() int {
 	return len(it.chain) - it.index
diff --git a/core/blockchain_repair_test.go b/core/blockchain_repair_test.go
index a4761f337b..07f154b4fa 100644
--- a/core/blockchain_repair_test.go
+++ b/core/blockchain_repair_test.go
@@ -1794,7 +1794,7 @@ func testRepairWithScheme(t *testing.T, tt *rewindTest, snapshots bool, scheme s
 		config.SnapshotLimit = 256
 		config.SnapshotWait = true
 	}
-	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -1859,7 +1859,7 @@ func testRepairWithScheme(t *testing.T, tt *rewindTest, snapshots bool, scheme s
 	}
 	defer db.Close()
 
-	newChain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
+	newChain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -1931,7 +1931,7 @@ func testIssue23496(t *testing.T, scheme string) {
 		}
 		engine = ethash.NewFullFaker()
 	)
-	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -1981,7 +1981,7 @@ func testIssue23496(t *testing.T, scheme string) {
 	}
 	defer db.Close()
 
-	chain, err = NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err = NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
diff --git a/core/blockchain_sethead_test.go b/core/blockchain_sethead_test.go
index 8b77f9f8b2..b06ed83616 100644
--- a/core/blockchain_sethead_test.go
+++ b/core/blockchain_sethead_test.go
@@ -1997,7 +1997,7 @@ func testSetHeadWithScheme(t *testing.T, tt *rewindTest, snapshots bool, scheme
 		config.SnapshotLimit = 256
 		config.SnapshotWait = true
 	}
-	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
diff --git a/core/blockchain_snapshot_test.go b/core/blockchain_snapshot_test.go
index 80f8035df1..45d33bb0a0 100644
--- a/core/blockchain_snapshot_test.go
+++ b/core/blockchain_snapshot_test.go
@@ -81,7 +81,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 		}
 		engine = ethash.NewFullFaker()
 	)
-	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(basic.scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(basic.scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -228,7 +228,7 @@ func (snaptest *snapshotTest) test(t *testing.T) {
 
 	// Restart the chain normally
 	chain.Stop()
-	newchain, err := NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -270,13 +270,13 @@ func (snaptest *crashSnapshotTest) test(t *testing.T) {
 	// the crash, we do restart twice here: one after the crash and one
 	// after the normal stop. It's used to ensure the broken snapshot
 	// can be detected all the time.
-	newchain, err := NewBlockChain(newdb, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(newdb, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
 	newchain.Stop()
 
-	newchain, err = NewBlockChain(newdb, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(newdb, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -313,7 +313,7 @@ func (snaptest *gappedSnapshotTest) test(t *testing.T) {
 		SnapshotLimit:  0,
 		StateScheme:    snaptest.scheme,
 	}
-	newchain, err := NewBlockChain(snaptest.db, cacheConfig, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, cacheConfig, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -321,7 +321,7 @@ func (snaptest *gappedSnapshotTest) test(t *testing.T) {
 	newchain.Stop()
 
 	// Restart the chain with enabling the snapshot
-	newchain, err = NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -349,7 +349,7 @@ func (snaptest *setHeadSnapshotTest) test(t *testing.T) {
 	chain.SetHead(snaptest.setHead)
 	chain.Stop()
 
-	newchain, err := NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -385,7 +385,7 @@ func (snaptest *wipeCrashSnapshotTest) test(t *testing.T) {
 		SnapshotLimit:  0,
 		StateScheme:    snaptest.scheme,
 	}
-	newchain, err := NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -402,7 +402,7 @@ func (snaptest *wipeCrashSnapshotTest) test(t *testing.T) {
 		SnapshotWait:   false, // Don't wait rebuild
 		StateScheme:    snaptest.scheme,
 	}
-	tmp, err := NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	tmp, err := NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -411,7 +411,7 @@ func (snaptest *wipeCrashSnapshotTest) test(t *testing.T) {
 	tmp.triedb.Close()
 	tmp.stopWithoutSaving()
 
-	newchain, err = NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(snaptest.db, DefaultCacheConfigWithScheme(snaptest.scheme), snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index 9148dd6f08..40f00982f2 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -22,6 +22,7 @@ import (
 	"math/big"
 	"math/rand"
 	"os"
+	"path"
 	"sync"
 	"testing"
 	"time"
@@ -61,7 +62,7 @@ func newCanonical(engine consensus.Engine, n int, full bool, scheme string) (eth
 		}
 	)
 	// Initialize a fresh chain with only a genesis block
-	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 
 	// Create and inject the requested chain
 	if n == 0 {
@@ -763,7 +764,7 @@ func testFastVsFullChains(t *testing.T, scheme string) {
 	})
 	// Import the chain as an archive node for the comparison baseline
 	archiveDb := rawdb.NewMemoryDatabase()
-	archive, _ := NewBlockChain(archiveDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	archive, _ := NewBlockChain(archiveDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer archive.Stop()
 
 	if n, err := archive.InsertChain(blocks); err != nil {
@@ -771,7 +772,7 @@ func testFastVsFullChains(t *testing.T, scheme string) {
 	}
 	// Fast import the chain as a non-archive node to test
 	fastDb := rawdb.NewMemoryDatabase()
-	fast, _ := NewBlockChain(fastDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	fast, _ := NewBlockChain(fastDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer fast.Stop()
 
 	headers := make([]*types.Header, len(blocks))
@@ -791,7 +792,7 @@ func testFastVsFullChains(t *testing.T, scheme string) {
 	}
 	defer ancientDb.Close()
 
-	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer ancient.Stop()
 
 	if n, err := ancient.InsertHeaderChain(headers); err != nil {
@@ -911,7 +912,7 @@ func testLightVsFastVsFullChainHeads(t *testing.T, scheme string) {
 	archiveCaching.TrieDirtyDisabled = true
 	archiveCaching.StateScheme = scheme
 
-	archive, _ := NewBlockChain(archiveDb, &archiveCaching, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	archive, _ := NewBlockChain(archiveDb, &archiveCaching, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if n, err := archive.InsertChain(blocks); err != nil {
 		t.Fatalf("failed to process block %d: %v", n, err)
 	}
@@ -924,7 +925,7 @@ func testLightVsFastVsFullChainHeads(t *testing.T, scheme string) {
 	// Import the chain as a non-archive node and ensure all pointers are updated
 	fastDb := makeDb()
 	defer fastDb.Close()
-	fast, _ := NewBlockChain(fastDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	fast, _ := NewBlockChain(fastDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer fast.Stop()
 
 	headers := make([]*types.Header, len(blocks))
@@ -944,7 +945,7 @@ func testLightVsFastVsFullChainHeads(t *testing.T, scheme string) {
 	// Import the chain as a ancient-first node and ensure all pointers are updated
 	ancientDb := makeDb()
 	defer ancientDb.Close()
-	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer ancient.Stop()
 
 	if n, err := ancient.InsertHeaderChain(headers); err != nil {
@@ -963,7 +964,7 @@ func testLightVsFastVsFullChainHeads(t *testing.T, scheme string) {
 	// Import the chain as a light node and ensure all pointers are updated
 	lightDb := makeDb()
 	defer lightDb.Close()
-	light, _ := NewBlockChain(lightDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	light, _ := NewBlockChain(lightDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if n, err := light.InsertHeaderChain(headers); err != nil {
 		t.Fatalf("failed to insert header %d: %v", n, err)
 	}
@@ -1036,7 +1037,7 @@ func testChainTxReorgs(t *testing.T, scheme string) {
 	})
 	// Import the chain. This runs all block validation rules.
 	db := rawdb.NewMemoryDatabase()
-	blockchain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if i, err := blockchain.InsertChain(chain); err != nil {
 		t.Fatalf("failed to insert original chain[%d]: %v", i, err)
 	}
@@ -1110,7 +1111,7 @@ func testLogReorgs(t *testing.T, scheme string) {
 		signer = types.LatestSigner(gspec.Config)
 	)
 
-	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	rmLogsCh := make(chan RemovedLogsEvent)
@@ -1166,7 +1167,7 @@ func testLogRebirth(t *testing.T, scheme string) {
 		gspec         = &Genesis{Config: params.TestChainConfig, Alloc: types.GenesisAlloc{addr1: {Balance: big.NewInt(10000000000000000)}}}
 		signer        = types.LatestSigner(gspec.Config)
 		engine        = ethash.NewFaker()
-		blockchain, _ = NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+		blockchain, _ = NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	)
 	defer blockchain.Stop()
 
@@ -1247,7 +1248,7 @@ func testSideLogRebirth(t *testing.T, scheme string) {
 		addr1         = crypto.PubkeyToAddress(key1.PublicKey)
 		gspec         = &Genesis{Config: params.TestChainConfig, Alloc: types.GenesisAlloc{addr1: {Balance: big.NewInt(10000000000000000)}}}
 		signer        = types.LatestSigner(gspec.Config)
-		blockchain, _ = NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+		blockchain, _ = NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	)
 	defer blockchain.Stop()
 
@@ -1266,7 +1267,7 @@ func testSideLogRebirth(t *testing.T, scheme string) {
 	}
 	checkLogEvents(t, newLogCh, rmLogsCh, 0, 0)
 
-	// Generate side chain with lower difficulty
+	// Generate side chain with lower difficulty, after the merge, the chain will be accepted even if it is lower difficulty
 	genDb, sideChain, _ := GenerateChainWithGenesis(gspec, ethash.NewFaker(), 2, func(i int, gen *BlockGen) {
 		if i == 1 {
 			tx, err := types.SignTx(types.NewContractCreation(gen.TxNonce(addr1), new(big.Int), 1000000, gen.header.BaseFee, logCode), signer, key1)
@@ -1279,14 +1280,14 @@ func testSideLogRebirth(t *testing.T, scheme string) {
 	if _, err := blockchain.InsertChain(sideChain); err != nil {
 		t.Fatalf("failed to insert forked chain: %v", err)
 	}
-	checkLogEvents(t, newLogCh, rmLogsCh, 0, 0)
+	checkLogEvents(t, newLogCh, rmLogsCh, 1, 0)
 
-	// Generate a new block based on side chain.
+	// Generate a new block based on side chain. Should not emit any events anymore.
 	newBlocks, _ := GenerateChain(gspec.Config, sideChain[len(sideChain)-1], ethash.NewFaker(), genDb, 1, func(i int, gen *BlockGen) {})
 	if _, err := blockchain.InsertChain(newBlocks); err != nil {
 		t.Fatalf("failed to insert forked chain: %v", err)
 	}
-	checkLogEvents(t, newLogCh, rmLogsCh, 1, 0)
+	checkLogEvents(t, newLogCh, rmLogsCh, 0, 0)
 }
 
 func checkLogEvents(t *testing.T, logsCh <-chan []*types.Log, rmLogsCh <-chan RemovedLogsEvent, wantNew, wantRemoved int) {
@@ -1346,7 +1347,7 @@ func testReorgSideEvent(t *testing.T, scheme string) {
 		}
 		signer = types.LatestSigner(gspec.Config)
 	)
-	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	_, chain, _ := GenerateChainWithGenesis(gspec, ethash.NewFaker(), 3, func(i int, gen *BlockGen) {})
@@ -1370,15 +1371,10 @@ func testReorgSideEvent(t *testing.T, scheme string) {
 		t.Fatalf("failed to insert chain: %v", err)
 	}
 
-	// first two block of the secondary chain are for a brief moment considered
-	// side chains because up to that point the first one is considered the
-	// heavier chain.
 	expectedSideHashes := map[common.Hash]bool{
-		replacementBlocks[0].Hash(): true,
-		replacementBlocks[1].Hash(): true,
-		chain[0].Hash():             true,
-		chain[1].Hash():             true,
-		chain[2].Hash():             true,
+		chain[0].Hash(): true,
+		chain[1].Hash(): true,
+		chain[2].Hash(): true,
 	}
 
 	i := 0
@@ -1403,7 +1399,7 @@ done:
 			timeout.Reset(timeoutDura)
 
 		case <-timeout.C:
-			t.Fatal("Timeout. Possibly not all blocks were triggered for sideevent")
+			t.Fatalf("Timeout. Possibly not all blocks were triggered for sideevent: %v", i)
 		}
 	}
 
@@ -1530,7 +1526,7 @@ func testEIP155Transition(t *testing.T, scheme string) {
 		}
 	})
 
-	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	if _, err := blockchain.InsertChain(blocks); err != nil {
@@ -1623,7 +1619,7 @@ func testEIP161AccountRemoval(t *testing.T, scheme string) {
 		block.AddTx(tx)
 	})
 	// account must exist pre eip 161
-	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	if _, err := blockchain.InsertChain(types.Blocks{blocks[0]}); err != nil {
@@ -1681,7 +1677,7 @@ func testBlockchainHeaderchainReorgConsistency(t *testing.T, scheme string) {
 	}
 	// Import the canonical and fork chain side by side, verifying the current block
 	// and current header consistency
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1725,7 +1721,7 @@ func TestTrieForkGC(t *testing.T) {
 		forks[i] = fork[0]
 	}
 	// Import the canonical and fork chain side by side, forcing the trie cache to cache both
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1771,7 +1767,7 @@ func testLargeReorgTrieGC(t *testing.T, scheme string) {
 	db, _ := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), "", "", false)
 	defer db.Close()
 
-	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1787,18 +1783,15 @@ func testLargeReorgTrieGC(t *testing.T, scheme string) {
 	if chain.HasState(shared[len(shared)-1].Root()) {
 		t.Fatalf("common-but-old ancestor still cache")
 	}
-	// Import the competitor chain without exceeding the canonical's TD and ensure
-	// we have not processed any of the blocks (protection against malicious blocks)
+	// Import the competitor chain without exceeding the canonical's TD.
+	// Post-merge the side chain should be executed
 	if _, err := chain.InsertChain(competitor[:len(competitor)-2]); err != nil {
 		t.Fatalf("failed to insert competitor chain: %v", err)
 	}
-	for i, block := range competitor[:len(competitor)-2] {
-		if chain.HasState(block.Root()) {
-			t.Fatalf("competitor %d: low TD chain became processed", i)
-		}
+	if !chain.HasState(competitor[len(competitor)-3].Root()) {
+		t.Fatalf("failed to insert low-TD chain")
 	}
-	// Import the head of the competitor chain, triggering the reorg and ensure we
-	// successfully reprocess all the stashed away blocks.
+	// Import the head of the competitor chain.
 	if _, err := chain.InsertChain(competitor[len(competitor)-2:]); err != nil {
 		t.Fatalf("failed to finalize competitor chain: %v", err)
 	}
@@ -1842,7 +1835,7 @@ func testBlockchainRecovery(t *testing.T, scheme string) {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
 	defer ancientDb.Close()
-	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 
 	headers := make([]*types.Header, len(blocks))
 	for i, block := range blocks {
@@ -1862,7 +1855,7 @@ func testBlockchainRecovery(t *testing.T, scheme string) {
 	rawdb.WriteHeadFastBlockHash(ancientDb, midBlock.Hash())
 
 	// Reopen broken blockchain again
-	ancient, _ = NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ = NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer ancient.Stop()
 	if num := ancient.CurrentBlock().Number.Uint64(); num != 0 {
 		t.Errorf("head block mismatch: have #%v, want #%v", num, 0)
@@ -1914,7 +1907,7 @@ func testInsertReceiptChainRollback(t *testing.T, scheme string) {
 	}
 	defer ancientDb.Close()
 
-	ancientChain, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancientChain, _ := NewBlockChain(ancientDb, DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer ancientChain.Stop()
 
 	// Import the canonical header chain.
@@ -1981,7 +1974,7 @@ func testLowDiffLongChain(t *testing.T, scheme string) {
 	diskdb, _ := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), "", "", false)
 	defer diskdb.Close()
 
-	chain, err := NewBlockChain(diskdb, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2042,7 +2035,7 @@ func testSideImport(t *testing.T, numCanonBlocksInSidechain, blocksBetweenCommon
 		mergeBlock = math.MaxInt32
 	)
 	// Generate and import the canonical chain
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2196,7 +2189,7 @@ func testInsertKnownChainData(t *testing.T, typ string, scheme string) {
 	}
 	defer chaindb.Close()
 
-	chain, err := NewBlockChain(chaindb, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(chaindb, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2280,10 +2273,10 @@ func testInsertKnownChainData(t *testing.T, typ string, scheme string) {
 	if err := inserter(append(blocks, blocks2...), append(receipts, receipts2...)); err != nil {
 		t.Fatalf("failed to insert chain data: %v", err)
 	}
-	// The head shouldn't change.
-	asserter(t, blocks3[len(blocks3)-1])
+	// Post-merge the chain should change even if td is lower.
+	asserter(t, blocks2[len(blocks2)-1])
 
-	// Rollback the heavier chain and re-insert the longer chain again
+	// Rollback the heavier chain and re-insert the longer chain again.
 	chain.SetHead(rollback - 1)
 	if err := inserter(append(blocks, blocks2...), append(receipts, receipts2...)); err != nil {
 		t.Fatalf("failed to insert chain data: %v", err)
@@ -2367,7 +2360,7 @@ func testInsertKnownChainDataWithMerging(t *testing.T, typ string, mergeHeight i
 	}
 	defer chaindb.Close()
 
-	chain, err := NewBlockChain(chaindb, nil, genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(chaindb, nil, genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2481,7 +2474,7 @@ func getLongAndShortChains(scheme string) (*BlockChain, []*types.Block, []*types
 	genDb, longChain, _ := GenerateChainWithGenesis(genesis, engine, 80, func(i int, b *BlockGen) {
 		b.SetCoinbase(common.Address{1})
 	})
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		return nil, nil, nil, nil, fmt.Errorf("failed to create tester chain: %v", err)
 	}
@@ -2657,7 +2650,7 @@ func benchmarkLargeNumberOfValueToNonexisting(b *testing.B, numTxs, numBlocks in
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		// Import the shared chain and the original canonical one
-		chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
 		if err != nil {
 			b.Fatalf("failed to create tester chain: %v", err)
 		}
@@ -2744,7 +2737,21 @@ func testSideImportPrunedBlocks(t *testing.T, scheme string) {
 	// Generate and import the canonical chain
 	_, blocks, _ := GenerateChainWithGenesis(genesis, engine, 2*state.TriesInMemory, nil)
 
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil, nil)
+	// Construct a database with freezer enabled
+	datadir := t.TempDir()
+	ancient := path.Join(datadir, "ancient")
+
+	db, err := rawdb.Open(rawdb.OpenOptions{
+		Directory:         datadir,
+		AncientsDirectory: ancient,
+		Ephemeral:         true,
+	})
+	if err != nil {
+		t.Fatalf("Failed to create persistent database: %v", err)
+	}
+	defer db.Close()
+
+	chain, err := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2771,7 +2778,6 @@ func testSideImportPrunedBlocks(t *testing.T, scheme string) {
 	if !chain.HasBlockAndState(firstNonPrunedBlock.Hash(), firstNonPrunedBlock.NumberU64()) {
 		t.Errorf("Block %d pruned", firstNonPrunedBlock.NumberU64())
 	}
-	// Now re-import some old blocks
 	blockToReimport := blocks[5:8]
 	_, err = chain.InsertChain(blockToReimport)
 	if err != nil {
@@ -2844,7 +2850,7 @@ func testDeleteCreateRevert(t *testing.T, scheme string) {
 		b.AddTx(tx)
 	})
 	// Import the canonical chain
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2959,7 +2965,7 @@ func testDeleteRecreateSlots(t *testing.T, scheme string) {
 	// Import the canonical chain
 	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{
 		Tracer: logger.NewJSONLogger(nil, os.Stdout),
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3041,7 +3047,7 @@ func testDeleteRecreateAccount(t *testing.T, scheme string) {
 	// Import the canonical chain
 	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{
 		Tracer: logger.NewJSONLogger(nil, os.Stdout),
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3217,7 +3223,7 @@ func testDeleteRecreateSlotsAcrossManyBlocks(t *testing.T, scheme string) {
 	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{
 		//Debug:  true,
 		//Tracer: vm.NewJSONLogger(nil, os.Stdout),
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3355,7 +3361,7 @@ func testInitThenFailCreateContract(t *testing.T, scheme string) {
 	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{
 		//Debug:  true,
 		//Tracer: vm.NewJSONLogger(nil, os.Stdout),
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3442,7 +3448,7 @@ func testEIP2718Transition(t *testing.T, scheme string) {
 	})
 
 	// Import the canonical chain
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3536,7 +3542,7 @@ func testEIP1559Transition(t *testing.T, scheme string) {
 
 		b.AddTx(tx)
 	})
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3649,7 +3655,7 @@ func testSetCanonical(t *testing.T, scheme string) {
 	diskdb, _ := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), "", "", false)
 	defer diskdb.Close()
 
-	chain, err := NewBlockChain(diskdb, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3758,7 +3764,7 @@ func testCanonicalHashMarker(t *testing.T, scheme string) {
 		_, forkB, _ := GenerateChainWithGenesis(gspec, engine, c.forkB, func(i int, gen *BlockGen) {})
 
 		// Initialize test chain
-		chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, engine, vm.Config{}, nil)
 		if err != nil {
 			t.Fatalf("failed to create tester chain: %v", err)
 		}
@@ -3895,7 +3901,7 @@ func testCreateThenDelete(t *testing.T, config *params.ChainConfig) {
 	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{
 		//Debug:  true,
 		//Tracer: logger.NewJSONLogger(nil, os.Stdout),
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -4007,7 +4013,7 @@ func TestDeleteThenCreate(t *testing.T) {
 		}
 	})
 	// Import the canonical chain
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -4092,7 +4098,7 @@ func TestTransientStorageReset(t *testing.T) {
 	})
 
 	// Initialize the blockchain with 1153 enabled.
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vmConfig, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vmConfig, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -4187,7 +4193,7 @@ func TestEIP3651(t *testing.T) {
 
 		b.AddTx(tx)
 	})
-	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{Tracer: logger.NewMarkdownLogger(&logger.Config{}, os.Stderr).Hooks()}, nil, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{Tracer: logger.NewMarkdownLogger(&logger.Config{}, os.Stderr).Hooks()}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
diff --git a/core/chain_makers_test.go b/core/chain_makers_test.go
index 6241f3fb69..61d09117bd 100644
--- a/core/chain_makers_test.go
+++ b/core/chain_makers_test.go
@@ -123,7 +123,7 @@ func TestGeneratePOSChain(t *testing.T) {
 	})
 
 	// Import the chain. This runs all block validation rules.
-	blockchain, _ := NewBlockChain(db, nil, gspec, nil, beacon.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, beacon.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	if i, err := blockchain.InsertChain(genchain); err != nil {
@@ -238,7 +238,7 @@ func ExampleGenerateChain() {
 	})
 
 	// Import the chain. This runs all block validation rules.
-	blockchain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(rawdb.HashScheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(rawdb.HashScheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	if i, err := blockchain.InsertChain(chain); err != nil {
diff --git a/core/dao_test.go b/core/dao_test.go
index b9a899ef2f..5da9e91b03 100644
--- a/core/dao_test.go
+++ b/core/dao_test.go
@@ -50,7 +50,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		BaseFee: big.NewInt(params.InitialBaseFee),
 		Config:  &proConf,
 	}
-	proBc, _ := NewBlockChain(proDb, nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	proBc, _ := NewBlockChain(proDb, nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer proBc.Stop()
 
 	conDb := rawdb.NewMemoryDatabase()
@@ -62,7 +62,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		BaseFee: big.NewInt(params.InitialBaseFee),
 		Config:  &conConf,
 	}
-	conBc, _ := NewBlockChain(conDb, nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	conBc, _ := NewBlockChain(conDb, nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer conBc.Stop()
 
 	if _, err := proBc.InsertChain(prefix); err != nil {
@@ -74,7 +74,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	// Try to expand both pro-fork and non-fork chains iteratively with other camp's blocks
 	for i := int64(0); i < params.DAOForkExtraRange.Int64(); i++ {
 		// Create a pro-fork block, and try to feed into the no-fork chain
-		bc, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+		bc, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 
 		blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().Number.Uint64()))
 		for j := 0; j < len(blocks)/2; j++ {
@@ -97,7 +97,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 			t.Fatalf("contra-fork chain didn't accepted no-fork block: %v", err)
 		}
 		// Create a no-fork block, and try to feed into the pro-fork chain
-		bc, _ = NewBlockChain(rawdb.NewMemoryDatabase(), nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+		bc, _ = NewBlockChain(rawdb.NewMemoryDatabase(), nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 
 		blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().Number.Uint64()))
 		for j := 0; j < len(blocks)/2; j++ {
@@ -121,7 +121,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		}
 	}
 	// Verify that contra-forkers accept pro-fork extra-datas after forking finishes
-	bc, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	bc, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer bc.Stop()
 
 	blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().Number.Uint64()))
@@ -139,7 +139,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		t.Fatalf("contra-fork chain didn't accept pro-fork block post-fork: %v", err)
 	}
 	// Verify that pro-forkers accept contra-fork extra-datas after forking finishes
-	bc, _ = NewBlockChain(rawdb.NewMemoryDatabase(), nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	bc, _ = NewBlockChain(rawdb.NewMemoryDatabase(), nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer bc.Stop()
 
 	blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().Number.Uint64()))
diff --git a/core/forkchoice.go b/core/forkchoice.go
deleted file mode 100644
index b293c851bf..0000000000
--- a/core/forkchoice.go
+++ /dev/null
@@ -1,113 +0,0 @@
-// Copyright 2021 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package core
-
-import (
-	crand "crypto/rand"
-	"errors"
-	"math/big"
-	mrand "math/rand"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/common/math"
-	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/params"
-)
-
-// ChainReader defines a small collection of methods needed to access the local
-// blockchain during header verification. It's implemented by both blockchain
-// and lightchain.
-type ChainReader interface {
-	// Config retrieves the header chain's chain configuration.
-	Config() *params.ChainConfig
-
-	// GetTd returns the total difficulty of a local block.
-	GetTd(common.Hash, uint64) *big.Int
-}
-
-// ForkChoice is the fork chooser based on the highest total difficulty of the
-// chain(the fork choice used in the eth1) and the external fork choice (the fork
-// choice used in the eth2). This main goal of this ForkChoice is not only for
-// offering fork choice during the eth1/2 merge phase, but also keep the compatibility
-// for all other proof-of-work networks.
-type ForkChoice struct {
-	chain ChainReader
-	rand  *mrand.Rand
-
-	// preserve is a helper function used in td fork choice.
-	// Miners will prefer to choose the local mined block if the
-	// local td is equal to the extern one. It can be nil for light
-	// client
-	preserve func(header *types.Header) bool
-}
-
-func NewForkChoice(chainReader ChainReader, preserve func(header *types.Header) bool) *ForkChoice {
-	// Seed a fast but crypto originating random generator
-	seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
-	if err != nil {
-		log.Crit("Failed to initialize random seed", "err", err)
-	}
-	return &ForkChoice{
-		chain:    chainReader,
-		rand:     mrand.New(mrand.NewSource(seed.Int64())),
-		preserve: preserve,
-	}
-}
-
-// ReorgNeeded returns whether the reorg should be applied
-// based on the given external header and local canonical chain.
-// In the td mode, the new head is chosen if the corresponding
-// total difficulty is higher. In the extern mode, the trusted
-// header is always selected as the head.
-func (f *ForkChoice) ReorgNeeded(current *types.Header, extern *types.Header) (bool, error) {
-	var (
-		localTD  = f.chain.GetTd(current.Hash(), current.Number.Uint64())
-		externTd = f.chain.GetTd(extern.Hash(), extern.Number.Uint64())
-	)
-	if localTD == nil || externTd == nil {
-		return false, errors.New("missing td")
-	}
-	// Accept the new header as the chain head if the transition
-	// is already triggered. We assume all the headers after the
-	// transition come from the trusted consensus layer.
-	if ttd := f.chain.Config().TerminalTotalDifficulty; ttd != nil && ttd.Cmp(externTd) <= 0 {
-		return true, nil
-	}
-
-	// If the total difficulty is higher than our known, add it to the canonical chain
-	if diff := externTd.Cmp(localTD); diff > 0 {
-		return true, nil
-	} else if diff < 0 {
-		return false, nil
-	}
-	// Local and external difficulty is identical.
-	// Second clause in the if statement reduces the vulnerability to selfish mining.
-	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
-	reorg := false
-	externNum, localNum := extern.Number.Uint64(), current.Number.Uint64()
-	if externNum < localNum {
-		reorg = true
-	} else if externNum == localNum {
-		var currentPreserve, externPreserve bool
-		if f.preserve != nil {
-			currentPreserve, externPreserve = f.preserve(current), f.preserve(extern)
-		}
-		reorg = !currentPreserve && (externPreserve || f.rand.Float64() < 0.5)
-	}
-	return reorg, nil
-}
diff --git a/core/genesis_test.go b/core/genesis_test.go
index fde458c4c8..0fee874138 100644
--- a/core/genesis_test.go
+++ b/core/genesis_test.go
@@ -124,7 +124,7 @@ func testSetupGenesis(t *testing.T, scheme string) {
 				tdb := triedb.NewDatabase(db, newDbConfig(scheme))
 				oldcustomg.Commit(db, tdb)
 
-				bc, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), &oldcustomg, nil, ethash.NewFullFaker(), vm.Config{}, nil, nil)
+				bc, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(scheme), &oldcustomg, nil, ethash.NewFullFaker(), vm.Config{}, nil)
 				defer bc.Stop()
 
 				_, blocks, _ := GenerateChainWithGenesis(&oldcustomg, ethash.NewFaker(), 4, nil)
diff --git a/core/headerchain.go b/core/headerchain.go
index 9ce8d11c40..c587a83fa6 100644
--- a/core/headerchain.go
+++ b/core/headerchain.go
@@ -254,7 +254,7 @@ func (hc *HeaderChain) WriteHeaders(headers []*types.Header) (int, error) {
 // without the real blocks. Hence, writing headers directly should only be done
 // in two scenarios: pure-header mode of operation (light clients), or properly
 // separated header/block phases (non-archive clients).
-func (hc *HeaderChain) writeHeadersAndSetHead(headers []*types.Header, forker *ForkChoice) (*headerWriteResult, error) {
+func (hc *HeaderChain) writeHeadersAndSetHead(headers []*types.Header) (*headerWriteResult, error) {
 	inserted, err := hc.WriteHeaders(headers)
 	if err != nil {
 		return nil, err
@@ -270,15 +270,6 @@ func (hc *HeaderChain) writeHeadersAndSetHead(headers []*types.Header, forker *F
 			lastHeader: lastHeader,
 		}
 	)
-	// Ask the fork choicer if the reorg is necessary
-	if reorg, err := forker.ReorgNeeded(hc.CurrentHeader(), lastHeader); err != nil {
-		return nil, err
-	} else if !reorg {
-		if inserted != 0 {
-			result.status = SideStatTy
-		}
-		return result, nil
-	}
 	// Special case, all the inserted headers are already on the canonical
 	// header chain, skip the reorg operation.
 	if hc.GetCanonicalHash(lastHeader.Number.Uint64()) == lastHash && lastHeader.Number.Uint64() <= hc.CurrentHeader().Number.Uint64() {
@@ -336,11 +327,11 @@ func (hc *HeaderChain) ValidateHeaderChain(chain []*types.Header) (int, error) {
 //
 // The returned 'write status' says if the inserted headers are part of the canonical chain
 // or a side chain.
-func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, start time.Time, forker *ForkChoice) (WriteStatus, error) {
+func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, start time.Time) (WriteStatus, error) {
 	if hc.procInterrupt() {
 		return 0, errors.New("aborted")
 	}
-	res, err := hc.writeHeadersAndSetHead(chain, forker)
+	res, err := hc.writeHeadersAndSetHead(chain)
 	if err != nil {
 		return 0, err
 	}
diff --git a/core/headerchain_test.go b/core/headerchain_test.go
index 25d9bfffcb..3228d82f0f 100644
--- a/core/headerchain_test.go
+++ b/core/headerchain_test.go
@@ -51,10 +51,10 @@ func verifyUnbrokenCanonchain(hc *HeaderChain) error {
 	return nil
 }
 
-func testInsert(t *testing.T, hc *HeaderChain, chain []*types.Header, wantStatus WriteStatus, wantErr error, forker *ForkChoice) {
+func testInsert(t *testing.T, hc *HeaderChain, chain []*types.Header, wantStatus WriteStatus, wantErr error) {
 	t.Helper()
 
-	status, err := hc.InsertHeaderChain(chain, time.Now(), forker)
+	status, err := hc.InsertHeaderChain(chain, time.Now())
 	if status != wantStatus {
 		t.Errorf("wrong write status from InsertHeaderChain: got %v, want %v", status, wantStatus)
 	}
@@ -83,34 +83,33 @@ func TestHeaderInsertion(t *testing.T) {
 	// chain B: G->A1->B1...B128
 	chainB := makeHeaderChain(gspec.Config, chainA[0], 128, ethash.NewFaker(), genDb, 10)
 
-	forker := NewForkChoice(hc, nil)
 	// Inserting 64 headers on an empty chain, expecting
 	// 1 callbacks, 1 canon-status, 0 sidestatus,
-	testInsert(t, hc, chainA[:64], CanonStatTy, nil, forker)
+	testInsert(t, hc, chainA[:64], CanonStatTy, nil)
 
 	// Inserting 64 identical headers, expecting
 	// 0 callbacks, 0 canon-status, 0 sidestatus,
-	testInsert(t, hc, chainA[:64], NonStatTy, nil, forker)
+	testInsert(t, hc, chainA[:64], NonStatTy, nil)
 
 	// Inserting the same some old, some new headers
 	// 1 callbacks, 1 canon, 0 side
-	testInsert(t, hc, chainA[32:96], CanonStatTy, nil, forker)
+	testInsert(t, hc, chainA[32:96], CanonStatTy, nil)
 
-	// Inserting side blocks, but not overtaking the canon chain
-	testInsert(t, hc, chainB[0:32], SideStatTy, nil, forker)
+	// Inserting headers from chain B, overtaking the canon chain blindly
+	testInsert(t, hc, chainB[0:32], CanonStatTy, nil)
 
-	// Inserting more side blocks, but we don't have the parent
-	testInsert(t, hc, chainB[34:36], NonStatTy, consensus.ErrUnknownAncestor, forker)
+	// Inserting more headers on chain B, but we don't have the parent
+	testInsert(t, hc, chainB[34:36], NonStatTy, consensus.ErrUnknownAncestor)
 
-	// Inserting more sideblocks, overtaking the canon chain
-	testInsert(t, hc, chainB[32:97], CanonStatTy, nil, forker)
+	// Inserting more headers on chain B, extend the canon chain
+	testInsert(t, hc, chainB[32:97], CanonStatTy, nil)
 
-	// Inserting more A-headers, taking back the canonicality
-	testInsert(t, hc, chainA[90:100], CanonStatTy, nil, forker)
+	// Inserting more headers on chain A, taking back the canonicality
+	testInsert(t, hc, chainA[90:100], CanonStatTy, nil)
 
 	// And B becomes canon again
-	testInsert(t, hc, chainB[97:107], CanonStatTy, nil, forker)
+	testInsert(t, hc, chainB[97:107], CanonStatTy, nil)
 
 	// And B becomes even longer
-	testInsert(t, hc, chainB[107:128], CanonStatTy, nil, forker)
+	testInsert(t, hc, chainB[107:128], CanonStatTy, nil)
 }
diff --git a/core/state_processor_test.go b/core/state_processor_test.go
index 4149cd2df3..3ed0eb7579 100644
--- a/core/state_processor_test.go
+++ b/core/state_processor_test.go
@@ -133,7 +133,7 @@ func TestStateProcessorErrors(t *testing.T) {
 					},
 				},
 			}
-			blockchain, _  = NewBlockChain(db, nil, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil, nil)
+			blockchain, _  = NewBlockChain(db, nil, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil)
 			tooBigInitCode = [params.MaxInitCodeSize + 1]byte{}
 		)
 
@@ -293,7 +293,7 @@ func TestStateProcessorErrors(t *testing.T) {
 					},
 				},
 			}
-			blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+			blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 		)
 		defer blockchain.Stop()
 		for i, tt := range []struct {
@@ -332,7 +332,7 @@ func TestStateProcessorErrors(t *testing.T) {
 					},
 				},
 			}
-			blockchain, _ = NewBlockChain(db, nil, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil, nil)
+			blockchain, _ = NewBlockChain(db, nil, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil)
 		)
 		defer blockchain.Stop()
 		for i, tt := range []struct {
@@ -481,7 +481,7 @@ func TestProcessVerkle(t *testing.T) {
 	// genesis := gspec.MustCommit(bcdb, triedb)
 	cacheConfig := DefaultCacheConfigWithScheme("path")
 	cacheConfig.SnapshotLimit = 0
-	blockchain, _ := NewBlockChain(bcdb, cacheConfig, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(bcdb, cacheConfig, gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil)
 	defer blockchain.Stop()
 
 	txCost1 := params.TxGas
diff --git a/eth/backend.go b/eth/backend.go
index 51011ed0b2..f7b67be4dc 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -216,11 +216,7 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 	if config.OverrideVerkle != nil {
 		overrides.OverrideVerkle = config.OverrideVerkle
 	}
-	// TODO (MariusVanDerWijden) get rid of shouldPreserve in a follow-up PR
-	shouldPreserve := func(header *types.Header) bool {
-		return false
-	}
-	eth.blockchain, err = core.NewBlockChain(chainDb, cacheConfig, config.Genesis, &overrides, eth.engine, vmConfig, shouldPreserve, &config.TransactionHistory)
+	eth.blockchain, err = core.NewBlockChain(chainDb, cacheConfig, config.Genesis, &overrides, eth.engine, vmConfig, &config.TransactionHistory)
 	if err != nil {
 		return nil, err
 	}
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index c440b40e9d..0f81e152ef 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -68,7 +68,7 @@ func newTesterWithNotification(t *testing.T, success func()) *downloadTester {
 		Alloc:   types.GenesisAlloc{testAddress: {Balance: big.NewInt(1000000000000000)}},
 		BaseFee: big.NewInt(params.InitialBaseFee),
 	}
-	chain, err := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if err != nil {
 		panic(err)
 	}
diff --git a/eth/downloader/testchain_test.go b/eth/downloader/testchain_test.go
index 6043f51372..8fa2e83413 100644
--- a/eth/downloader/testchain_test.go
+++ b/eth/downloader/testchain_test.go
@@ -217,7 +217,7 @@ func newTestBlockchain(blocks []*types.Block) *core.BlockChain {
 		if pregenerated {
 			panic("Requested chain generation outside of init")
 		}
-		chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, testGspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+		chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, testGspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 		if err != nil {
 			panic(err)
 		}
diff --git a/eth/filters/filter_test.go b/eth/filters/filter_test.go
index 2b3efb51b1..d8b703fee4 100644
--- a/eth/filters/filter_test.go
+++ b/eth/filters/filter_test.go
@@ -250,7 +250,7 @@ func TestFilters(t *testing.T) {
 		}
 	})
 	var l uint64
-	bc, err := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, &l)
+	bc, err := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, &l)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/eth/gasprice/gasprice_test.go b/eth/gasprice/gasprice_test.go
index 39f3c79b98..fdba2e584b 100644
--- a/eth/gasprice/gasprice_test.go
+++ b/eth/gasprice/gasprice_test.go
@@ -210,7 +210,7 @@ func newTestBackend(t *testing.T, londonBlock *big.Int, cancunBlock *big.Int, pe
 	})
 	// Construct testing chain
 	gspec.Config.TerminalTotalDifficulty = new(big.Int).SetUint64(td)
-	chain, err := core.NewBlockChain(db, &core.CacheConfig{TrieCleanNoPrefetch: true}, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, &core.CacheConfig{TrieCleanNoPrefetch: true}, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("Failed to create local chain, %v", err)
 	}
diff --git a/eth/handler_eth_test.go b/eth/handler_eth_test.go
index a38059ca95..c41c9abc26 100644
--- a/eth/handler_eth_test.go
+++ b/eth/handler_eth_test.go
@@ -98,8 +98,8 @@ func testForkIDSplit(t *testing.T, protocol uint) {
 		gspecNoFork  = &core.Genesis{Config: configNoFork}
 		gspecProFork = &core.Genesis{Config: configProFork}
 
-		chainNoFork, _  = core.NewBlockChain(dbNoFork, nil, gspecNoFork, nil, engine, vm.Config{}, nil, nil)
-		chainProFork, _ = core.NewBlockChain(dbProFork, nil, gspecProFork, nil, engine, vm.Config{}, nil, nil)
+		chainNoFork, _  = core.NewBlockChain(dbNoFork, nil, gspecNoFork, nil, engine, vm.Config{}, nil)
+		chainProFork, _ = core.NewBlockChain(dbProFork, nil, gspecProFork, nil, engine, vm.Config{}, nil)
 
 		_, blocksNoFork, _  = core.GenerateChainWithGenesis(gspecNoFork, engine, 2, nil)
 		_, blocksProFork, _ = core.GenerateChainWithGenesis(gspecProFork, engine, 2, nil)
diff --git a/eth/handler_test.go b/eth/handler_test.go
index bcc8ea30e4..7b250df2e9 100644
--- a/eth/handler_test.go
+++ b/eth/handler_test.go
@@ -151,7 +151,7 @@ func newTestHandlerWithBlocks(blocks int) *testHandler {
 		Config: params.TestChainConfig,
 		Alloc:  types.GenesisAlloc{testAddr: {Balance: big.NewInt(1000000)}},
 	}
-	chain, _ := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 
 	_, bs, _ := core.GenerateChainWithGenesis(gspec, ethash.NewFaker(), blocks, nil)
 	if _, err := chain.InsertChain(bs); err != nil {
diff --git a/eth/protocols/eth/handler_test.go b/eth/protocols/eth/handler_test.go
index 934dadc9a5..fc82b42947 100644
--- a/eth/protocols/eth/handler_test.go
+++ b/eth/protocols/eth/handler_test.go
@@ -104,7 +104,7 @@ func newTestBackendWithGenerator(blocks int, shanghai bool, generator func(int,
 		Config: config,
 		Alloc:  types.GenesisAlloc{testAddr: {Balance: big.NewInt(100_000_000_000_000_000)}},
 	}
-	chain, _ := core.NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil)
 
 	_, bs, _ := core.GenerateChainWithGenesis(gspec, engine, blocks, generator)
 	if _, err := chain.InsertChain(bs); err != nil {
diff --git a/eth/protocols/snap/handler_fuzzing_test.go b/eth/protocols/snap/handler_fuzzing_test.go
index 4e234ad21b..777db6387c 100644
--- a/eth/protocols/snap/handler_fuzzing_test.go
+++ b/eth/protocols/snap/handler_fuzzing_test.go
@@ -126,7 +126,7 @@ func getChain() *core.BlockChain {
 		SnapshotWait:        true,
 	}
 	trieRoot = blocks[len(blocks)-1].Root()
-	bc, _ := core.NewBlockChain(rawdb.NewMemoryDatabase(), cacheConf, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
+	bc, _ := core.NewBlockChain(rawdb.NewMemoryDatabase(), cacheConf, gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	if _, err := bc.InsertChain(blocks); err != nil {
 		panic(err)
 	}
diff --git a/eth/tracers/api_test.go b/eth/tracers/api_test.go
index e717f5352d..47e3693495 100644
--- a/eth/tracers/api_test.go
+++ b/eth/tracers/api_test.go
@@ -81,7 +81,7 @@ func newTestBackend(t *testing.T, n int, gspec *core.Genesis, generator func(i i
 		SnapshotLimit:     0,
 		TrieDirtyDisabled: true, // Archive mode
 	}
-	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, gspec, nil, backend.engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, gspec, nil, backend.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1014,7 +1014,7 @@ func newTestMergedBackend(t *testing.T, n int, gspec *core.Genesis, generator fu
 		SnapshotLimit:     0,
 		TrieDirtyDisabled: true, // Archive mode
 	}
-	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, gspec, nil, backend.engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, gspec, nil, backend.engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
diff --git a/eth/tracers/internal/tracetest/supply_test.go b/eth/tracers/internal/tracetest/supply_test.go
index d608b1e002..5c11b5e472 100644
--- a/eth/tracers/internal/tracetest/supply_test.go
+++ b/eth/tracers/internal/tracetest/supply_test.go
@@ -557,7 +557,7 @@ func testSupplyTracer(t *testing.T, genesis *core.Genesis, gen func(*core.BlockG
 		return nil, nil, fmt.Errorf("failed to create call tracer: %v", err)
 	}
 
-	chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), core.DefaultCacheConfigWithScheme(rawdb.PathScheme), genesis, nil, engine, vm.Config{Tracer: tracer}, nil, nil)
+	chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), core.DefaultCacheConfigWithScheme(rawdb.PathScheme), genesis, nil, engine, vm.Config{Tracer: tracer}, nil)
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to create tester chain: %v", err)
 	}
diff --git a/internal/ethapi/api_test.go b/internal/ethapi/api_test.go
index 7465fb5529..3c5da840d3 100644
--- a/internal/ethapi/api_test.go
+++ b/internal/ethapi/api_test.go
@@ -449,7 +449,7 @@ func newTestBackend(t *testing.T, n int, gspec *core.Genesis, engine consensus.E
 	// Generate blocks for testing
 	db, blocks, _ := core.GenerateChainWithGenesis(gspec, engine, n, generator)
 	txlookupLimit := uint64(0)
-	chain, err := core.NewBlockChain(db, cacheConfig, gspec, nil, engine, vm.Config{}, nil, &txlookupLimit)
+	chain, err := core.NewBlockChain(db, cacheConfig, gspec, nil, engine, vm.Config{}, &txlookupLimit)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
diff --git a/miner/miner_test.go b/miner/miner_test.go
index da133ad8d0..779626c045 100644
--- a/miner/miner_test.go
+++ b/miner/miner_test.go
@@ -152,7 +152,7 @@ func createMiner(t *testing.T) *Miner {
 	// Create consensus engine
 	engine := clique.New(chainConfig.Clique, chainDB)
 	// Create Ethereum backend
-	bc, err := core.NewBlockChain(chainDB, nil, genesis, nil, engine, vm.Config{}, nil, nil)
+	bc, err := core.NewBlockChain(chainDB, nil, genesis, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("can't create new chain %v", err)
 	}
diff --git a/miner/payload_building_test.go b/miner/payload_building_test.go
index ac9b2ab704..7a235d88e1 100644
--- a/miner/payload_building_test.go
+++ b/miner/payload_building_test.go
@@ -121,7 +121,7 @@ func newTestWorkerBackend(t *testing.T, chainConfig *params.ChainConfig, engine
 	default:
 		t.Fatalf("unexpected consensus engine type: %T", engine)
 	}
-	chain, err := core.NewBlockChain(db, &core.CacheConfig{TrieDirtyDisabled: true}, gspec, nil, engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, &core.CacheConfig{TrieDirtyDisabled: true}, gspec, nil, engine, vm.Config{}, nil)
 	if err != nil {
 		t.Fatalf("core.NewBlockChain failed: %v", err)
 	}
diff --git a/tests/block_test.go b/tests/block_test.go
index 52184eb274..4bbd2571d7 100644
--- a/tests/block_test.go
+++ b/tests/block_test.go
@@ -49,6 +49,17 @@ func TestBlockchain(t *testing.T) {
 	// using 4.6 TGas
 	bt.skipLoad(`.*randomStatetest94.json.*`)
 
+	// After the merge we would accept side chains as canonical even if they have lower td
+	bt.skipLoad(`.*bcMultiChainTest/ChainAtoChainB_difficultyB.json`)
+	bt.skipLoad(`.*bcMultiChainTest/CallContractFromNotBestBlock.json`)
+	bt.skipLoad(`.*bcTotalDifficultyTest/uncleBlockAtBlock3afterBlock4.json`)
+	bt.skipLoad(`.*bcTotalDifficultyTest/lotsOfBranchesOverrideAtTheMiddle.json`)
+	bt.skipLoad(`.*bcTotalDifficultyTest/sideChainWithMoreTransactions.json`)
+	bt.skipLoad(`.*bcForkStressTest/ForkStressTest.json`)
+	bt.skipLoad(`.*bcMultiChainTest/lotsOfLeafs.json`)
+	bt.skipLoad(`.*bcFrontierToHomestead/blockChainFrontierWithLargerTDvsHomesteadBlockchain.json`)
+	bt.skipLoad(`.*bcFrontierToHomestead/blockChainFrontierWithLargerTDvsHomesteadBlockchain2.json`)
+
 	bt.walk(t, blockTestDir, func(t *testing.T, name string, test *BlockTest) {
 		execBlockTest(t, bt, test)
 	})
diff --git a/tests/block_test_util.go b/tests/block_test_util.go
index 62aa582c82..b3957601bb 100644
--- a/tests/block_test_util.go
+++ b/tests/block_test_util.go
@@ -153,7 +153,7 @@ func (t *BlockTest) Run(snapshotter bool, scheme string, witness bool, tracer *t
 	chain, err := core.NewBlockChain(db, cache, gspec, nil, engine, vm.Config{
 		Tracer:                  tracer,
 		EnableWitnessCollection: witness,
-	}, nil, nil)
+	}, nil)
 	if err != nil {
 		return err
 	}