diff --git a/core/blockchain.go b/core/blockchain.go
index e234b5a5ba53..4f12690f4baa 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -244,10 +244,7 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 		engine:        engine,
 		vmConfig:      vmConfig,
 	}
-	bc.forker = NewForkChoice(bc, merger.LeftPoW(), shouldPreserve)
-	merger.SubscribeLeavePoW(func() {
-		bc.forker.MarkTransitioned()
-	})
+	bc.forker = NewForkChoice(bc, shouldPreserve)
 	bc.validator = NewBlockValidator(chainConfig, bc, engine)
 	bc.prefetcher = newStatePrefetcher(chainConfig, bc, engine)
 	bc.processor = NewStateProcessor(chainConfig, bc, engine)
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index f1e130b19ff1..99db78fcf707 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -230,9 +230,6 @@ func testInsertAfterMerge(t *testing.T, blockchain *BlockChain, i, n int, full b
 		t.Errorf("chain content mismatch at %d: have hash %v, want hash %v", i, hash2, hash1)
 	}
 
-	// Trigger the transition explicitly
-	blockchain2.forker.MarkTransitioned()
-
 	// Extend the newly created chain
 	if full {
 		blockChainB := makeBlockChain(blockchain2.CurrentBlock(), n, ethash.NewFaker(), db, forkSeed)
@@ -1963,7 +1960,6 @@ func testSideImport(t *testing.T, numCanonBlocksInSidechain, blocksBetweenCommon
 	if mergePoint == 0 {
 		genEngine.MarkTransitioned()
 		runEngine.MarkTransitioned()
-		chain.forker.MarkTransitioned()
 	}
 	blocks, _ := GenerateChain(params.TestChainConfig, genesis, genEngine, db, 2*TriesInMemory, func(i int, gen *BlockGen) {
 		tx, err := types.SignTx(types.NewTransaction(nonce, common.HexToAddress("deadbeef"), big.NewInt(100), 21000, big.NewInt(int64(i+1)*params.GWei), nil), signer, key)
@@ -1994,7 +1990,6 @@ func testSideImport(t *testing.T, numCanonBlocksInSidechain, blocksBetweenCommon
 	if mergePoint == 1 {
 		genEngine.MarkTransitioned()
 		runEngine.MarkTransitioned()
-		chain.forker.MarkTransitioned()
 	}
 
 	// Generate the sidechain
@@ -2218,9 +2213,6 @@ func testInsertKnownChainDataWithMerging(t *testing.T, typ string, mergeHeight i
 		if engine != nil {
 			engine.MarkTransitioned()
 		}
-		if forker != nil {
-			forker.MarkTransitioned()
-		}
 	}
 
 	// Apply merging since genesis
diff --git a/core/forkchoice.go b/core/forkchoice.go
index 9bc1f79facef..e3b8e591201f 100644
--- a/core/forkchoice.go
+++ b/core/forkchoice.go
@@ -27,12 +27,16 @@ import (
 	"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
 }
@@ -45,12 +49,7 @@ type ChainReader interface {
 type ForkChoice struct {
 	chain ChainReader
 	rand  *mrand.Rand
-
-	// transitioned is the flag whether the chain has started(or finished)
-	// the transition. It's triggered by receiving the first "NewHead" message
-	// from the external consensus engine.
-	transitioned bool
-	lock         sync.RWMutex
+	lock  sync.RWMutex
 
 	// preserve is a helper function used in td fork choice.
 	// Miners will prefer to choose the local mined block if the
@@ -59,17 +58,16 @@ type ForkChoice struct {
 	preserve func(header *types.Header) bool
 }
 
-func NewForkChoice(chainReader ChainReader, transitioned bool, preserve func(header *types.Header) bool) *ForkChoice {
+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())),
-		transitioned: transitioned,
-		preserve:     preserve,
+		chain:    chainReader,
+		rand:     mrand.New(mrand.NewSource(seed.Int64())),
+		preserve: preserve,
 	}
 }
 
@@ -82,12 +80,6 @@ func (f *ForkChoice) Reorg(current *types.Header, header *types.Header) (bool, e
 	f.lock.RLock()
 	defer f.lock.RUnlock()
 
-	// 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 f.transitioned {
-		return true, nil
-	}
 	var (
 		localTD  = f.chain.GetTd(current.Hash(), current.Number.Uint64())
 		externTd = f.chain.GetTd(header.Hash(), header.Number.Uint64())
@@ -95,6 +87,12 @@ func (f *ForkChoice) Reorg(current *types.Header, header *types.Header) (bool, e
 	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
 	// Second clause in the if statement reduces the vulnerability to selfish mining.
 	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
@@ -113,11 +111,3 @@ func (f *ForkChoice) Reorg(current *types.Header, header *types.Header) (bool, e
 	}
 	return reorg, nil
 }
-
-// MarkTransitioned marks the transition has started.
-func (f *ForkChoice) MarkTransitioned() {
-	f.lock.Lock()
-	defer f.lock.Unlock()
-
-	f.transitioned = true
-}
diff --git a/core/headerchain_test.go b/core/headerchain_test.go
index 5371ff98642d..ed0522671fb8 100644
--- a/core/headerchain_test.go
+++ b/core/headerchain_test.go
@@ -84,7 +84,7 @@ func TestHeaderInsertion(t *testing.T) {
 	chainB := makeHeaderChain(chainA[0], 128, ethash.NewFaker(), db, 10)
 	log.Root().SetHandler(log.StdoutHandler)
 
-	forker := NewForkChoice(hc, false, nil)
+	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)
diff --git a/eth/catalyst/api.go b/eth/catalyst/api.go
index 344acb9eb4b3..77144cb78998 100644
--- a/eth/catalyst/api.go
+++ b/eth/catalyst/api.go
@@ -231,7 +231,7 @@ func (api *ConsensusAPI) ExecutePayload(params ExecutableData) (GenericStringRes
 		if parent == nil {
 			return INVALID, fmt.Errorf("could not find parent %x", params.ParentHash)
 		}
-		block, err := ExecutableDataToBlock(api.les.BlockChain().Config(), parent, params)
+		block, err := ExecutableDataToBlock(params)
 		if err != nil {
 			return INVALID, err
 		}
@@ -240,17 +240,7 @@ func (api *ConsensusAPI) ExecutePayload(params ExecutableData) (GenericStringRes
 		}
 		return VALID, nil
 	}
-	parent := api.eth.BlockChain().GetBlockByHash(params.ParentHash)
-	if parent == nil {
-		return INVALID, fmt.Errorf("could not find parent %x", params.ParentHash)
-	}
-
-	td := api.eth.BlockChain().GetTdByHash(parent.Hash())
-	ttd := api.eth.BlockChain().Config().TerminalTotalDifficulty
-	if td.Cmp(ttd) < 0 {
-		return INVALID, fmt.Errorf("can not execute payload on top of block with low td got: %v threshold %v", td, ttd)
-	}
-	block, err := ExecutableDataToBlock(api.eth.BlockChain().Config(), parent.Header(), params)
+	block, err := ExecutableDataToBlock(params)
 	if err != nil {
 		return INVALID, err
 	}
@@ -260,6 +250,12 @@ func (api *ConsensusAPI) ExecutePayload(params ExecutableData) (GenericStringRes
 		}
 		return SYNCING, nil
 	}
+	parent := api.eth.BlockChain().GetBlockByHash(params.ParentHash)
+	td := api.eth.BlockChain().GetTdByHash(parent.Hash())
+	ttd := api.eth.BlockChain().Config().TerminalTotalDifficulty
+	if td.Cmp(ttd) < 0 {
+		return INVALID, fmt.Errorf("can not execute payload on top of block with low td got: %v threshold %v", td, ttd)
+	}
 	if err := api.eth.BlockChain().InsertBlock(block); err != nil {
 		return INVALID, err
 	}
@@ -392,7 +388,7 @@ func decodeTransactions(enc [][]byte) ([]*types.Transaction, error) {
 	return txs, nil
 }
 
-func ExecutableDataToBlock(config *chainParams.ChainConfig, parent *types.Header, params ExecutableData) (*types.Block, error) {
+func ExecutableDataToBlock(params ExecutableData) (*types.Block, error) {
 	txs, err := decodeTransactions(params.Transactions)
 	if err != nil {
 		return nil, err
@@ -419,9 +415,6 @@ func ExecutableDataToBlock(config *chainParams.ChainConfig, parent *types.Header
 		Extra:       params.ExtraData,
 		// TODO (MariusVanDerWijden) add params.Random to header once required
 	}
-	if config.IsLondon(number) {
-		header.BaseFee = misc.CalcBaseFee(config, parent)
-	}
 	block := types.NewBlockWithHeader(header).WithBody(txs, nil /* uncles */)
 	if block.Hash() != params.BlockHash {
 		return nil, fmt.Errorf("blockhash mismatch, want %x, got %x", params.BlockHash, block.Hash())
diff --git a/eth/catalyst/api_test.go b/eth/catalyst/api_test.go
index 720a678ceac6..50db1a82b940 100644
--- a/eth/catalyst/api_test.go
+++ b/eth/catalyst/api_test.go
@@ -255,7 +255,7 @@ func TestEth2NewBlock(t *testing.T) {
 		if err != nil {
 			t.Fatalf("Failed to create the executable data %v", err)
 		}
-		block, err := ExecutableDataToBlock(ethservice.BlockChain().Config(), parent.Header(), *execData)
+		block, err := ExecutableDataToBlock(*execData)
 		if err != nil {
 			t.Fatalf("Failed to convert executable data to block %v", err)
 		}
@@ -292,7 +292,7 @@ func TestEth2NewBlock(t *testing.T) {
 		if err != nil {
 			t.Fatalf("Failed to create the executable data %v", err)
 		}
-		block, err := ExecutableDataToBlock(ethservice.BlockChain().Config(), parent.Header(), *execData)
+		block, err := ExecutableDataToBlock(*execData)
 		if err != nil {
 			t.Fatalf("Failed to convert executable data to block %v", err)
 		}
diff --git a/light/lightchain.go b/light/lightchain.go
index 93d474a967e2..6bb621ff2994 100644
--- a/light/lightchain.go
+++ b/light/lightchain.go
@@ -93,10 +93,7 @@ func NewLightChain(odr OdrBackend, config *params.ChainConfig, engine consensus.
 		blockCache:    blockCache,
 		engine:        engine,
 	}
-	bc.forker = core.NewForkChoice(bc, merger.LeftPoW(), nil)
-	merger.SubscribeLeavePoW(func() {
-		bc.forker.MarkTransitioned()
-	})
+	bc.forker = core.NewForkChoice(bc, nil)
 	var err error
 	bc.hc, err = core.NewHeaderChain(odr.Database(), config, bc.engine, bc.getProcInterrupt)
 	if err != nil {
diff --git a/miner/stress/beacon/main.go b/miner/stress/beacon/main.go
index 46bf6d7e1476..dc5c229410cf 100644
--- a/miner/stress/beacon/main.go
+++ b/miner/stress/beacon/main.go
@@ -172,13 +172,7 @@ func (n *ethNode) insertBlockAndSetHead(parent *types.Header, ed catalyst.Execut
 	if err := n.insertBlock(ed); err != nil {
 		return err
 	}
-	var config *params.ChainConfig
-	if n.typ == eth2LightClient {
-		config = n.lesBackend.BlockChain().Config()
-	} else {
-		config = n.ethBackend.BlockChain().Config()
-	}
-	block, err := catalyst.ExecutableDataToBlock(config, parent, ed)
+	block, err := catalyst.ExecutableDataToBlock(ed)
 	if err != nil {
 		return err
 	}
@@ -319,7 +313,7 @@ func (mgr *nodeManager) run() {
 				log.Error("Failed to assemble the block", "err", err)
 				continue
 			}
-			block, _ := catalyst.ExecutableDataToBlock(chain.Config(), parentBlock.Header(), *ed)
+			block, _ := catalyst.ExecutableDataToBlock(*ed)
 
 			nodes := mgr.getNodes(eth2MiningNode)
 			nodes = append(nodes, mgr.getNodes(eth2NormalNode)...)