diff --git a/cmd/geth/config.go b/cmd/geth/config.go
index 7a642edd0..ea4e65162 100644
--- a/cmd/geth/config.go
+++ b/cmd/geth/config.go
@@ -161,7 +161,7 @@ func makeFullNode(ctx *cli.Context) (*node.Node, ethapi.Backend) {
 	if ctx.GlobalIsSet(utils.OverrideTerminalTotalDifficulty.Name) {
 		cfg.Eth.OverrideTerminalTotalDifficulty = new(big.Int).SetUint64(ctx.GlobalUint64(utils.OverrideTerminalTotalDifficulty.Name))
 	}
-	backend, _ := utils.RegisterEthService(stack, &cfg.Eth, ctx.GlobalBool(utils.CatalystFlag.Name))
+	backend, _ := utils.RegisterEthService(stack, &cfg.Eth)
 
 	// Configure GraphQL if requested
 	if ctx.GlobalIsSet(utils.GraphQLEnabledFlag.Name) {
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index a6f7b2d50..94a0b16a8 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -157,7 +157,6 @@ var (
 		utils.GpoIgnoreGasPriceFlag,
 		utils.MinerNotifyFullFlag,
 		configFileFlag,
-		utils.CatalystFlag,
 	}
 
 	rpcFlags = []cli.Flag{
diff --git a/cmd/geth/usage.go b/cmd/geth/usage.go
index c63c62fd3..417fba689 100644
--- a/cmd/geth/usage.go
+++ b/cmd/geth/usage.go
@@ -229,7 +229,6 @@ var AppHelpFlagGroups = []flags.FlagGroup{
 			utils.SnapshotFlag,
 			utils.BloomFilterSizeFlag,
 			cli.HelpFlag,
-			utils.CatalystFlag,
 		},
 	},
 }
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index 586eeca40..7d11b0631 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -790,11 +790,6 @@ var (
 		Usage: "InfluxDB organization name (v2 only)",
 		Value: metrics.DefaultConfig.InfluxDBOrganization,
 	}
-
-	CatalystFlag = cli.BoolFlag{
-		Name:  "catalyst",
-		Usage: "Catalyst mode (eth2 integration testing)",
-	}
 )
 
 // MakeDataDir retrieves the currently requested data directory, terminating
@@ -1717,14 +1712,14 @@ func SetDNSDiscoveryDefaults(cfg *ethconfig.Config, genesis common.Hash) {
 // RegisterEthService adds an Ethereum client to the stack.
 // The second return value is the full node instance, which may be nil if the
 // node is running as a light client.
-func RegisterEthService(stack *node.Node, cfg *ethconfig.Config, isCatalyst bool) (ethapi.Backend, *eth.Ethereum) {
+func RegisterEthService(stack *node.Node, cfg *ethconfig.Config) (ethapi.Backend, *eth.Ethereum) {
 	if cfg.SyncMode == downloader.LightSync {
 		backend, err := les.New(stack, cfg)
 		if err != nil {
 			Fatalf("Failed to register the Ethereum service: %v", err)
 		}
 		stack.RegisterAPIs(tracers.APIs(backend.ApiBackend))
-		if isCatalyst {
+		if backend.BlockChain().Config().TerminalTotalDifficulty != nil {
 			if err := lescatalyst.Register(stack, backend); err != nil {
 				Fatalf("Failed to register the catalyst service: %v", err)
 			}
@@ -1741,7 +1736,7 @@ func RegisterEthService(stack *node.Node, cfg *ethconfig.Config, isCatalyst bool
 			Fatalf("Failed to create the LES server: %v", err)
 		}
 	}
-	if isCatalyst {
+	if backend.BlockChain().Config().TerminalTotalDifficulty != nil {
 		if err := ethcatalyst.Register(stack, backend); err != nil {
 			Fatalf("Failed to register the catalyst service: %v", err)
 		}