diff --git a/cmd/geth/chaincmd.go b/cmd/geth/chaincmd.go
index 1f78979198..ba20272174 100644
--- a/cmd/geth/chaincmd.go
+++ b/cmd/geth/chaincmd.go
@@ -161,6 +161,7 @@ The export-preimages command export hash preimages to an RLP encoded stream`,
 			utils.RinkebyFlag,
 			utils.TxLookupLimitFlag,
 			utils.GoerliFlag,
+			utils.YoloV1Flag,
 			utils.LegacyTestnetFlag,
 		},
 		Category: "BLOCKCHAIN COMMANDS",
@@ -210,6 +211,7 @@ Use "ethereum dump 0" to dump the genesis block.`,
 			utils.RopstenFlag,
 			utils.RinkebyFlag,
 			utils.GoerliFlag,
+			utils.YoloV1Flag,
 			utils.LegacyTestnetFlag,
 			utils.SyncModeFlag,
 		},
diff --git a/cmd/geth/consolecmd.go b/cmd/geth/consolecmd.go
index 8773208adf..2a304636eb 100644
--- a/cmd/geth/consolecmd.go
+++ b/cmd/geth/consolecmd.go
@@ -136,6 +136,8 @@ func remoteConsole(ctx *cli.Context) error {
 				path = filepath.Join(path, "rinkeby")
 			} else if ctx.GlobalBool(utils.GoerliFlag.Name) {
 				path = filepath.Join(path, "goerli")
+			} else if ctx.GlobalBool(utils.YoloV1Flag.Name) {
+				path = filepath.Join(path, "yolo-v1")
 			}
 		}
 		endpoint = fmt.Sprintf("%s/geth.ipc", path)
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 80ef17c594..b232b8e807 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -140,6 +140,7 @@ var (
 		utils.RopstenFlag,
 		utils.RinkebyFlag,
 		utils.GoerliFlag,
+		utils.YoloV1Flag,
 		utils.VMEnableDebugFlag,
 		utils.NetworkIdFlag,
 		utils.EthStatsURLFlag,
diff --git a/cmd/geth/usage.go b/cmd/geth/usage.go
index 1ae9a77271..5c429056e9 100644
--- a/cmd/geth/usage.go
+++ b/cmd/geth/usage.go
@@ -74,6 +74,7 @@ var AppHelpFlagGroups = []flagGroup{
 			utils.NetworkIdFlag,
 			utils.GoerliFlag,
 			utils.RinkebyFlag,
+			utils.YoloV1Flag,
 			utils.RopstenFlag,
 			utils.SyncModeFlag,
 			utils.ExitWhenSyncedFlag,
diff --git a/cmd/puppeth/wizard_genesis.go b/cmd/puppeth/wizard_genesis.go
index 8832de13ab..40327d25d2 100644
--- a/cmd/puppeth/wizard_genesis.go
+++ b/cmd/puppeth/wizard_genesis.go
@@ -235,6 +235,10 @@ func (w *wizard) manageGenesis() {
 		fmt.Printf("Which block should Istanbul come into effect? (default = %v)\n", w.conf.Genesis.Config.IstanbulBlock)
 		w.conf.Genesis.Config.IstanbulBlock = w.readDefaultBigInt(w.conf.Genesis.Config.IstanbulBlock)
 
+		fmt.Println()
+		fmt.Printf("Which block should YOLOv1 come into effect? (default = %v)\n", w.conf.Genesis.Config.YoloV1Block)
+		w.conf.Genesis.Config.YoloV1Block = w.readDefaultBigInt(w.conf.Genesis.Config.YoloV1Block)
+
 		out, _ := json.MarshalIndent(w.conf.Genesis.Config, "", "  ")
 		fmt.Printf("Chain configuration updated:\n\n%s\n", out)
 
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index c29a1bed73..19d7e99a43 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -169,6 +169,10 @@ var (
 		Name:  "goerli",
 		Usage: "Görli network: pre-configured proof-of-authority test network",
 	}
+	YoloV1Flag = cli.BoolFlag{
+		Name:  "yolov1",
+		Usage: "YOLOv1 network: pre-configured proof-of-authority shortlived test network.",
+	}
 	RinkebyFlag = cli.BoolFlag{
 		Name:  "rinkeby",
 		Usage: "Rinkeby network: pre-configured proof-of-authority test network",
@@ -744,6 +748,9 @@ func MakeDataDir(ctx *cli.Context) string {
 		if ctx.GlobalBool(GoerliFlag.Name) {
 			return filepath.Join(path, "goerli")
 		}
+		if ctx.GlobalBool(YoloV1Flag.Name) {
+			return filepath.Join(path, "yolo-v1")
+		}
 		return path
 	}
 	Fatalf("Cannot determine default data directory, please set manually (--datadir)")
@@ -800,6 +807,8 @@ func setBootstrapNodes(ctx *cli.Context, cfg *p2p.Config) {
 		urls = params.RinkebyBootnodes
 	case ctx.GlobalBool(GoerliFlag.Name):
 		urls = params.GoerliBootnodes
+	case ctx.GlobalBool(YoloV1Flag.Name):
+		urls = params.YoloV1Bootnodes
 	case cfg.BootstrapNodes != nil:
 		return // already set, don't apply defaults.
 	}
@@ -834,6 +843,8 @@ func setBootstrapNodesV5(ctx *cli.Context, cfg *p2p.Config) {
 		urls = params.RinkebyBootnodes
 	case ctx.GlobalBool(GoerliFlag.Name):
 		urls = params.GoerliBootnodes
+	case ctx.GlobalBool(YoloV1Flag.Name):
+		urls = params.YoloV1Bootnodes
 	case cfg.BootstrapNodesV5 != nil:
 		return // already set, don't apply defaults.
 	}
@@ -1264,6 +1275,8 @@ func setDataDir(ctx *cli.Context, cfg *node.Config) {
 		cfg.DataDir = filepath.Join(node.DefaultDataDir(), "rinkeby")
 	case ctx.GlobalBool(GoerliFlag.Name) && cfg.DataDir == node.DefaultDataDir():
 		cfg.DataDir = filepath.Join(node.DefaultDataDir(), "goerli")
+	case ctx.GlobalBool(YoloV1Flag.Name) && cfg.DataDir == node.DefaultDataDir():
+		cfg.DataDir = filepath.Join(node.DefaultDataDir(), "yolo-v1")
 	}
 }
 
@@ -1471,7 +1484,7 @@ func SetShhConfig(ctx *cli.Context, stack *node.Node, cfg *whisper.Config) {
 // SetEthConfig applies eth-related command line flags to the config.
 func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 	// Avoid conflicting network flags
-	CheckExclusive(ctx, DeveloperFlag, LegacyTestnetFlag, RopstenFlag, RinkebyFlag, GoerliFlag)
+	CheckExclusive(ctx, DeveloperFlag, LegacyTestnetFlag, RopstenFlag, RinkebyFlag, GoerliFlag, YoloV1Flag)
 	CheckExclusive(ctx, LegacyLightServFlag, LightServeFlag, SyncModeFlag, "light")
 	CheckExclusive(ctx, DeveloperFlag, ExternalSignerFlag) // Can't use both ephemeral unlocked and external signer
 	CheckExclusive(ctx, GCModeFlag, "archive", TxLookupLimitFlag)
@@ -1576,6 +1589,11 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 		}
 		cfg.Genesis = core.DefaultGoerliGenesisBlock()
 		setDNSDiscoveryDefaults(cfg, params.GoerliGenesisHash)
+	case ctx.GlobalBool(YoloV1Flag.Name):
+		if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
+			cfg.NetworkId = 133519467574833 // "yolov1"
+		}
+		cfg.Genesis = core.DefaultYoloV1GenesisBlock()
 	case ctx.GlobalBool(DeveloperFlag.Name):
 		if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
 			cfg.NetworkId = 1337
@@ -1758,6 +1776,8 @@ func MakeGenesis(ctx *cli.Context) *core.Genesis {
 		genesis = core.DefaultRinkebyGenesisBlock()
 	case ctx.GlobalBool(GoerliFlag.Name):
 		genesis = core.DefaultGoerliGenesisBlock()
+	case ctx.GlobalBool(YoloV1Flag.Name):
+		genesis = core.DefaultYoloV1GenesisBlock()
 	case ctx.GlobalBool(DeveloperFlag.Name):
 		Fatalf("Developer chains are ephemeral")
 	}
diff --git a/core/genesis.go b/core/genesis.go
index 3528262b5b..655736906f 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -242,6 +242,8 @@ func (g *Genesis) configOrDefault(ghash common.Hash) *params.ChainConfig {
 		return params.RinkebyChainConfig
 	case ghash == params.GoerliGenesisHash:
 		return params.GoerliChainConfig
+	case ghash == params.YoloV1GenesisHash:
+		return params.YoloV1ChainConfig
 	default:
 		return params.AllEthashProtocolChanges
 	}
@@ -377,6 +379,17 @@ func DefaultGoerliGenesisBlock() *Genesis {
 	}
 }
 
+func DefaultYoloV1GenesisBlock() *Genesis {
+	return &Genesis{
+		Config:     params.YoloV1ChainConfig,
+		Timestamp:  0x5ed754f1,
+		ExtraData:  hexutil.MustDecode("0x00000000000000000000000000000000000000000000000000000000000000008a37866fd3627c9205a37c8685666f32ec07bb1b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
+		GasLimit:   0x47b760,
+		Difficulty: big.NewInt(1),
+		Alloc:      decodePrealloc(yoloV1AllocData),
+	}
+}
+
 // DeveloperGenesisBlock returns the 'geth --dev' genesis block.
 func DeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis {
 	// Override the default period to the user requested one
diff --git a/core/genesis_alloc.go b/core/genesis_alloc.go
index 9d9417222c..3e03d16407 100644
--- a/core/genesis_alloc.go
+++ b/core/genesis_alloc.go
@@ -25,3 +25,4 @@ const mainnetAllocData = "\xfa\x04]X\u0793\r\x83b\x011\x8e\u0189\x9agT\x06\x908'
 const ropstenAllocData = "\xf9\x03\xa4\u0080\x01\xc2\x01\x01\xc2\x02\x01\xc2\x03\x01\xc2\x04\x01\xc2\x05\x01\xc2\x06\x01\xc2\a\x01\xc2\b\x01\xc2\t\x01\xc2\n\x80\xc2\v\x80\xc2\f\x80\xc2\r\x80\xc2\x0e\x80\xc2\x0f\x80\xc2\x10\x80\xc2\x11\x80\xc2\x12\x80\xc2\x13\x80\xc2\x14\x80\xc2\x15\x80\xc2\x16\x80\xc2\x17\x80\xc2\x18\x80\xc2\x19\x80\xc2\x1a\x80\xc2\x1b\x80\xc2\x1c\x80\xc2\x1d\x80\xc2\x1e\x80\xc2\x1f\x80\xc2 \x80\xc2!\x80\xc2\"\x80\xc2#\x80\xc2$\x80\xc2%\x80\xc2&\x80\xc2'\x80\xc2(\x80\xc2)\x80\xc2*\x80\xc2+\x80\xc2,\x80\xc2-\x80\xc2.\x80\xc2/\x80\xc20\x80\xc21\x80\xc22\x80\xc23\x80\xc24\x80\xc25\x80\xc26\x80\xc27\x80\xc28\x80\xc29\x80\xc2:\x80\xc2;\x80\xc2<\x80\xc2=\x80\xc2>\x80\xc2?\x80\xc2@\x80\xc2A\x80\xc2B\x80\xc2C\x80\xc2D\x80\xc2E\x80\xc2F\x80\xc2G\x80\xc2H\x80\xc2I\x80\xc2J\x80\xc2K\x80\xc2L\x80\xc2M\x80\xc2N\x80\xc2O\x80\xc2P\x80\xc2Q\x80\xc2R\x80\xc2S\x80\xc2T\x80\xc2U\x80\xc2V\x80\xc2W\x80\xc2X\x80\xc2Y\x80\xc2Z\x80\xc2[\x80\xc2\\\x80\xc2]\x80\xc2^\x80\xc2_\x80\xc2`\x80\xc2a\x80\xc2b\x80\xc2c\x80\xc2d\x80\xc2e\x80\xc2f\x80\xc2g\x80\xc2h\x80\xc2i\x80\xc2j\x80\xc2k\x80\xc2l\x80\xc2m\x80\xc2n\x80\xc2o\x80\xc2p\x80\xc2q\x80\xc2r\x80\xc2s\x80\xc2t\x80\xc2u\x80\xc2v\x80\xc2w\x80\xc2x\x80\xc2y\x80\xc2z\x80\xc2{\x80\xc2|\x80\xc2}\x80\xc2~\x80\xc2\u007f\x80\u00c1\x80\x80\u00c1\x81\x80\u00c1\x82\x80\u00c1\x83\x80\u00c1\x84\x80\u00c1\x85\x80\u00c1\x86\x80\u00c1\x87\x80\u00c1\x88\x80\u00c1\x89\x80\u00c1\x8a\x80\u00c1\x8b\x80\u00c1\x8c\x80\u00c1\x8d\x80\u00c1\x8e\x80\u00c1\x8f\x80\u00c1\x90\x80\u00c1\x91\x80\u00c1\x92\x80\u00c1\x93\x80\u00c1\x94\x80\u00c1\x95\x80\u00c1\x96\x80\u00c1\x97\x80\u00c1\x98\x80\u00c1\x99\x80\u00c1\x9a\x80\u00c1\x9b\x80\u00c1\x9c\x80\u00c1\x9d\x80\u00c1\x9e\x80\u00c1\x9f\x80\u00c1\xa0\x80\u00c1\xa1\x80\u00c1\xa2\x80\u00c1\xa3\x80\u00c1\xa4\x80\u00c1\xa5\x80\u00c1\xa6\x80\u00c1\xa7\x80\u00c1\xa8\x80\u00c1\xa9\x80\u00c1\xaa\x80\u00c1\xab\x80\u00c1\xac\x80\u00c1\xad\x80\u00c1\xae\x80\u00c1\xaf\x80\u00c1\xb0\x80\u00c1\xb1\x80\u00c1\xb2\x80\u00c1\xb3\x80\u00c1\xb4\x80\u00c1\xb5\x80\u00c1\xb6\x80\u00c1\xb7\x80\u00c1\xb8\x80\u00c1\xb9\x80\u00c1\xba\x80\u00c1\xbb\x80\u00c1\xbc\x80\u00c1\xbd\x80\u00c1\xbe\x80\u00c1\xbf\x80\u00c1\xc0\x80\u00c1\xc1\x80\u00c1\u0080\u00c1\u00c0\u00c1\u0100\u00c1\u0140\u00c1\u0180\u00c1\u01c0\u00c1\u0200\u00c1\u0240\u00c1\u0280\u00c1\u02c0\u00c1\u0300\u00c1\u0340\u00c1\u0380\u00c1\u03c0\u00c1\u0400\u00c1\u0440\u00c1\u0480\u00c1\u04c0\u00c1\u0500\u00c1\u0540\u00c1\u0580\u00c1\u05c0\u00c1\u0600\u00c1\u0640\u00c1\u0680\u00c1\u06c0\u00c1\u0700\u00c1\u0740\u00c1\u0780\u00c1\u07c0\u00c1\xe0\x80\u00c1\xe1\x80\u00c1\xe2\x80\u00c1\xe3\x80\u00c1\xe4\x80\u00c1\xe5\x80\u00c1\xe6\x80\u00c1\xe7\x80\u00c1\xe8\x80\u00c1\xe9\x80\u00c1\xea\x80\u00c1\xeb\x80\u00c1\xec\x80\u00c1\xed\x80\u00c1\xee\x80\u00c1\xef\x80\u00c1\xf0\x80\u00c1\xf1\x80\u00c1\xf2\x80\u00c1\xf3\x80\u00c1\xf4\x80\u00c1\xf5\x80\u00c1\xf6\x80\u00c1\xf7\x80\u00c1\xf8\x80\u00c1\xf9\x80\u00c1\xfa\x80\u00c1\xfb\x80\u00c1\xfc\x80\u00c1\xfd\x80\u00c1\xfe\x80\u00c1\xff\x80\u3507KT\xa8\xbd\x15)f\xd6?pk\xae\x1f\xfe\xb0A\x19!\xe5\x8d\f\x9f,\x9c\xd0Ft\xed\xea@\x00\x00\x00"
 const rinkebyAllocData = "\xf9\x03\xb7\u0080\x01\xc2\x01\x01\xc2\x02\x01\xc2\x03\x01\xc2\x04\x01\xc2\x05\x01\xc2\x06\x01\xc2\a\x01\xc2\b\x01\xc2\t\x01\xc2\n\x01\xc2\v\x01\xc2\f\x01\xc2\r\x01\xc2\x0e\x01\xc2\x0f\x01\xc2\x10\x01\xc2\x11\x01\xc2\x12\x01\xc2\x13\x01\xc2\x14\x01\xc2\x15\x01\xc2\x16\x01\xc2\x17\x01\xc2\x18\x01\xc2\x19\x01\xc2\x1a\x01\xc2\x1b\x01\xc2\x1c\x01\xc2\x1d\x01\xc2\x1e\x01\xc2\x1f\x01\xc2 \x01\xc2!\x01\xc2\"\x01\xc2#\x01\xc2$\x01\xc2%\x01\xc2&\x01\xc2'\x01\xc2(\x01\xc2)\x01\xc2*\x01\xc2+\x01\xc2,\x01\xc2-\x01\xc2.\x01\xc2/\x01\xc20\x01\xc21\x01\xc22\x01\xc23\x01\xc24\x01\xc25\x01\xc26\x01\xc27\x01\xc28\x01\xc29\x01\xc2:\x01\xc2;\x01\xc2<\x01\xc2=\x01\xc2>\x01\xc2?\x01\xc2@\x01\xc2A\x01\xc2B\x01\xc2C\x01\xc2D\x01\xc2E\x01\xc2F\x01\xc2G\x01\xc2H\x01\xc2I\x01\xc2J\x01\xc2K\x01\xc2L\x01\xc2M\x01\xc2N\x01\xc2O\x01\xc2P\x01\xc2Q\x01\xc2R\x01\xc2S\x01\xc2T\x01\xc2U\x01\xc2V\x01\xc2W\x01\xc2X\x01\xc2Y\x01\xc2Z\x01\xc2[\x01\xc2\\\x01\xc2]\x01\xc2^\x01\xc2_\x01\xc2`\x01\xc2a\x01\xc2b\x01\xc2c\x01\xc2d\x01\xc2e\x01\xc2f\x01\xc2g\x01\xc2h\x01\xc2i\x01\xc2j\x01\xc2k\x01\xc2l\x01\xc2m\x01\xc2n\x01\xc2o\x01\xc2p\x01\xc2q\x01\xc2r\x01\xc2s\x01\xc2t\x01\xc2u\x01\xc2v\x01\xc2w\x01\xc2x\x01\xc2y\x01\xc2z\x01\xc2{\x01\xc2|\x01\xc2}\x01\xc2~\x01\xc2\u007f\x01\u00c1\x80\x01\u00c1\x81\x01\u00c1\x82\x01\u00c1\x83\x01\u00c1\x84\x01\u00c1\x85\x01\u00c1\x86\x01\u00c1\x87\x01\u00c1\x88\x01\u00c1\x89\x01\u00c1\x8a\x01\u00c1\x8b\x01\u00c1\x8c\x01\u00c1\x8d\x01\u00c1\x8e\x01\u00c1\x8f\x01\u00c1\x90\x01\u00c1\x91\x01\u00c1\x92\x01\u00c1\x93\x01\u00c1\x94\x01\u00c1\x95\x01\u00c1\x96\x01\u00c1\x97\x01\u00c1\x98\x01\u00c1\x99\x01\u00c1\x9a\x01\u00c1\x9b\x01\u00c1\x9c\x01\u00c1\x9d\x01\u00c1\x9e\x01\u00c1\x9f\x01\u00c1\xa0\x01\u00c1\xa1\x01\u00c1\xa2\x01\u00c1\xa3\x01\u00c1\xa4\x01\u00c1\xa5\x01\u00c1\xa6\x01\u00c1\xa7\x01\u00c1\xa8\x01\u00c1\xa9\x01\u00c1\xaa\x01\u00c1\xab\x01\u00c1\xac\x01\u00c1\xad\x01\u00c1\xae\x01\u00c1\xaf\x01\u00c1\xb0\x01\u00c1\xb1\x01\u00c1\xb2\x01\u00c1\xb3\x01\u00c1\xb4\x01\u00c1\xb5\x01\u00c1\xb6\x01\u00c1\xb7\x01\u00c1\xb8\x01\u00c1\xb9\x01\u00c1\xba\x01\u00c1\xbb\x01\u00c1\xbc\x01\u00c1\xbd\x01\u00c1\xbe\x01\u00c1\xbf\x01\u00c1\xc0\x01\u00c1\xc1\x01\u00c1\xc2\x01\u00c1\xc3\x01\u00c1\xc4\x01\u00c1\xc5\x01\u00c1\xc6\x01\u00c1\xc7\x01\u00c1\xc8\x01\u00c1\xc9\x01\u00c1\xca\x01\u00c1\xcb\x01\u00c1\xcc\x01\u00c1\xcd\x01\u00c1\xce\x01\u00c1\xcf\x01\u00c1\xd0\x01\u00c1\xd1\x01\u00c1\xd2\x01\u00c1\xd3\x01\u00c1\xd4\x01\u00c1\xd5\x01\u00c1\xd6\x01\u00c1\xd7\x01\u00c1\xd8\x01\u00c1\xd9\x01\u00c1\xda\x01\u00c1\xdb\x01\u00c1\xdc\x01\u00c1\xdd\x01\u00c1\xde\x01\u00c1\xdf\x01\u00c1\xe0\x01\u00c1\xe1\x01\u00c1\xe2\x01\u00c1\xe3\x01\u00c1\xe4\x01\u00c1\xe5\x01\u00c1\xe6\x01\u00c1\xe7\x01\u00c1\xe8\x01\u00c1\xe9\x01\u00c1\xea\x01\u00c1\xeb\x01\u00c1\xec\x01\u00c1\xed\x01\u00c1\xee\x01\u00c1\xef\x01\u00c1\xf0\x01\u00c1\xf1\x01\u00c1\xf2\x01\u00c1\xf3\x01\u00c1\xf4\x01\u00c1\xf5\x01\u00c1\xf6\x01\u00c1\xf7\x01\u00c1\xf8\x01\u00c1\xf9\x01\u00c1\xfa\x01\u00c1\xfb\x01\u00c1\xfc\x01\u00c1\xfd\x01\u00c1\xfe\x01\u00c1\xff\x01\xf6\x941\xb9\x8d\x14\x00{\xde\xe67)\x80\x86\x98\x8a\v\xbd1\x18E#\xa0\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
 const goerliAllocData = "\xf9\x04\x06\u0080\x01\xc2\x01\x01\xc2\x02\x01\xc2\x03\x01\xc2\x04\x01\xc2\x05\x01\xc2\x06\x01\xc2\a\x01\xc2\b\x01\xc2\t\x01\xc2\n\x01\xc2\v\x01\xc2\f\x01\xc2\r\x01\xc2\x0e\x01\xc2\x0f\x01\xc2\x10\x01\xc2\x11\x01\xc2\x12\x01\xc2\x13\x01\xc2\x14\x01\xc2\x15\x01\xc2\x16\x01\xc2\x17\x01\xc2\x18\x01\xc2\x19\x01\xc2\x1a\x01\xc2\x1b\x01\xc2\x1c\x01\xc2\x1d\x01\xc2\x1e\x01\xc2\x1f\x01\xc2 \x01\xc2!\x01\xc2\"\x01\xc2#\x01\xc2$\x01\xc2%\x01\xc2&\x01\xc2'\x01\xc2(\x01\xc2)\x01\xc2*\x01\xc2+\x01\xc2,\x01\xc2-\x01\xc2.\x01\xc2/\x01\xc20\x01\xc21\x01\xc22\x01\xc23\x01\xc24\x01\xc25\x01\xc26\x01\xc27\x01\xc28\x01\xc29\x01\xc2:\x01\xc2;\x01\xc2<\x01\xc2=\x01\xc2>\x01\xc2?\x01\xc2@\x01\xc2A\x01\xc2B\x01\xc2C\x01\xc2D\x01\xc2E\x01\xc2F\x01\xc2G\x01\xc2H\x01\xc2I\x01\xc2J\x01\xc2K\x01\xc2L\x01\xc2M\x01\xc2N\x01\xc2O\x01\xc2P\x01\xc2Q\x01\xc2R\x01\xc2S\x01\xc2T\x01\xc2U\x01\xc2V\x01\xc2W\x01\xc2X\x01\xc2Y\x01\xc2Z\x01\xc2[\x01\xc2\\\x01\xc2]\x01\xc2^\x01\xc2_\x01\xc2`\x01\xc2a\x01\xc2b\x01\xc2c\x01\xc2d\x01\xc2e\x01\xc2f\x01\xc2g\x01\xc2h\x01\xc2i\x01\xc2j\x01\xc2k\x01\xc2l\x01\xc2m\x01\xc2n\x01\xc2o\x01\xc2p\x01\xc2q\x01\xc2r\x01\xc2s\x01\xc2t\x01\xc2u\x01\xc2v\x01\xc2w\x01\xc2x\x01\xc2y\x01\xc2z\x01\xc2{\x01\xc2|\x01\xc2}\x01\xc2~\x01\xc2\u007f\x01\u00c1\x80\x01\u00c1\x81\x01\u00c1\x82\x01\u00c1\x83\x01\u00c1\x84\x01\u00c1\x85\x01\u00c1\x86\x01\u00c1\x87\x01\u00c1\x88\x01\u00c1\x89\x01\u00c1\x8a\x01\u00c1\x8b\x01\u00c1\x8c\x01\u00c1\x8d\x01\u00c1\x8e\x01\u00c1\x8f\x01\u00c1\x90\x01\u00c1\x91\x01\u00c1\x92\x01\u00c1\x93\x01\u00c1\x94\x01\u00c1\x95\x01\u00c1\x96\x01\u00c1\x97\x01\u00c1\x98\x01\u00c1\x99\x01\u00c1\x9a\x01\u00c1\x9b\x01\u00c1\x9c\x01\u00c1\x9d\x01\u00c1\x9e\x01\u00c1\x9f\x01\u00c1\xa0\x01\u00c1\xa1\x01\u00c1\xa2\x01\u00c1\xa3\x01\u00c1\xa4\x01\u00c1\xa5\x01\u00c1\xa6\x01\u00c1\xa7\x01\u00c1\xa8\x01\u00c1\xa9\x01\u00c1\xaa\x01\u00c1\xab\x01\u00c1\xac\x01\u00c1\xad\x01\u00c1\xae\x01\u00c1\xaf\x01\u00c1\xb0\x01\u00c1\xb1\x01\u00c1\xb2\x01\u00c1\xb3\x01\u00c1\xb4\x01\u00c1\xb5\x01\u00c1\xb6\x01\u00c1\xb7\x01\u00c1\xb8\x01\u00c1\xb9\x01\u00c1\xba\x01\u00c1\xbb\x01\u00c1\xbc\x01\u00c1\xbd\x01\u00c1\xbe\x01\u00c1\xbf\x01\u00c1\xc0\x01\u00c1\xc1\x01\u00c1\xc2\x01\u00c1\xc3\x01\u00c1\xc4\x01\u00c1\xc5\x01\u00c1\xc6\x01\u00c1\xc7\x01\u00c1\xc8\x01\u00c1\xc9\x01\u00c1\xca\x01\u00c1\xcb\x01\u00c1\xcc\x01\u00c1\xcd\x01\u00c1\xce\x01\u00c1\xcf\x01\u00c1\xd0\x01\u00c1\xd1\x01\u00c1\xd2\x01\u00c1\xd3\x01\u00c1\xd4\x01\u00c1\xd5\x01\u00c1\xd6\x01\u00c1\xd7\x01\u00c1\xd8\x01\u00c1\xd9\x01\u00c1\xda\x01\u00c1\xdb\x01\u00c1\xdc\x01\u00c1\xdd\x01\u00c1\xde\x01\u00c1\xdf\x01\u00c1\xe0\x01\u00c1\xe1\x01\u00c1\xe2\x01\u00c1\xe3\x01\u00c1\xe4\x01\u00c1\xe5\x01\u00c1\xe6\x01\u00c1\xe7\x01\u00c1\xe8\x01\u00c1\xe9\x01\u00c1\xea\x01\u00c1\xeb\x01\u00c1\xec\x01\u00c1\xed\x01\u00c1\xee\x01\u00c1\xef\x01\u00c1\xf0\x01\u00c1\xf1\x01\u00c1\xf2\x01\u00c1\xf3\x01\u00c1\xf4\x01\u00c1\xf5\x01\u00c1\xf6\x01\u00c1\xf7\x01\u00c1\xf8\x01\u00c1\xf9\x01\u00c1\xfa\x01\u00c1\xfb\x01\u00c1\xfc\x01\u00c1\xfd\x01\u00c1\xfe\x01\u00c1\xff\x01\xe0\x94L*\xe4\x82Y5\x05\xf0\x16<\xde\xfc\a>\x81\xc6<\xdaA\a\x8a\x15-\x02\xc7\xe1J\xf6\x80\x00\x00\xe0\x94\xa8\xe8\xf1G2e\x8eKQ\xe8q\x191\x05:\x8ai\xba\xf2\xb1\x8a\x15-\x02\xc7\xe1J\xf6\x80\x00\x00\xe1\x94\u0665\x17\x9f\t\x1d\x85\x05\x1d<\x98'\x85\xef\xd1E\\\uc199\x8b\bE\x95\x16\x14\x01HJ\x00\x00\x00\xe1\x94\u08bdBX\xd2v\x887\xba\xa2j(\xfeq\xdc\a\x9f\x84\u01cbJG\xe3\xc1$H\xf4\xad\x00\x00\x00"
+const yoloV1AllocData = "\xf9\x03\xb7\u0080\x01\xc2\x01\x01\xc2\x02\x01\xc2\x03\x01\xc2\x04\x01\xc2\x05\x01\xc2\x06\x01\xc2\a\x01\xc2\b\x01\xc2\t\x01\xc2\n\x01\xc2\v\x01\xc2\f\x01\xc2\r\x01\xc2\x0e\x01\xc2\x0f\x01\xc2\x10\x01\xc2\x11\x01\xc2\x12\x01\xc2\x13\x01\xc2\x14\x01\xc2\x15\x01\xc2\x16\x01\xc2\x17\x01\xc2\x18\x01\xc2\x19\x01\xc2\x1a\x01\xc2\x1b\x01\xc2\x1c\x01\xc2\x1d\x01\xc2\x1e\x01\xc2\x1f\x01\xc2 \x01\xc2!\x01\xc2\"\x01\xc2#\x01\xc2$\x01\xc2%\x01\xc2&\x01\xc2'\x01\xc2(\x01\xc2)\x01\xc2*\x01\xc2+\x01\xc2,\x01\xc2-\x01\xc2.\x01\xc2/\x01\xc20\x01\xc21\x01\xc22\x01\xc23\x01\xc24\x01\xc25\x01\xc26\x01\xc27\x01\xc28\x01\xc29\x01\xc2:\x01\xc2;\x01\xc2<\x01\xc2=\x01\xc2>\x01\xc2?\x01\xc2@\x01\xc2A\x01\xc2B\x01\xc2C\x01\xc2D\x01\xc2E\x01\xc2F\x01\xc2G\x01\xc2H\x01\xc2I\x01\xc2J\x01\xc2K\x01\xc2L\x01\xc2M\x01\xc2N\x01\xc2O\x01\xc2P\x01\xc2Q\x01\xc2R\x01\xc2S\x01\xc2T\x01\xc2U\x01\xc2V\x01\xc2W\x01\xc2X\x01\xc2Y\x01\xc2Z\x01\xc2[\x01\xc2\\\x01\xc2]\x01\xc2^\x01\xc2_\x01\xc2`\x01\xc2a\x01\xc2b\x01\xc2c\x01\xc2d\x01\xc2e\x01\xc2f\x01\xc2g\x01\xc2h\x01\xc2i\x01\xc2j\x01\xc2k\x01\xc2l\x01\xc2m\x01\xc2n\x01\xc2o\x01\xc2p\x01\xc2q\x01\xc2r\x01\xc2s\x01\xc2t\x01\xc2u\x01\xc2v\x01\xc2w\x01\xc2x\x01\xc2y\x01\xc2z\x01\xc2{\x01\xc2|\x01\xc2}\x01\xc2~\x01\xc2\u007f\x01\u00c1\x80\x01\u00c1\x81\x01\u00c1\x82\x01\u00c1\x83\x01\u00c1\x84\x01\u00c1\x85\x01\u00c1\x86\x01\u00c1\x87\x01\u00c1\x88\x01\u00c1\x89\x01\u00c1\x8a\x01\u00c1\x8b\x01\u00c1\x8c\x01\u00c1\x8d\x01\u00c1\x8e\x01\u00c1\x8f\x01\u00c1\x90\x01\u00c1\x91\x01\u00c1\x92\x01\u00c1\x93\x01\u00c1\x94\x01\u00c1\x95\x01\u00c1\x96\x01\u00c1\x97\x01\u00c1\x98\x01\u00c1\x99\x01\u00c1\x9a\x01\u00c1\x9b\x01\u00c1\x9c\x01\u00c1\x9d\x01\u00c1\x9e\x01\u00c1\x9f\x01\u00c1\xa0\x01\u00c1\xa1\x01\u00c1\xa2\x01\u00c1\xa3\x01\u00c1\xa4\x01\u00c1\xa5\x01\u00c1\xa6\x01\u00c1\xa7\x01\u00c1\xa8\x01\u00c1\xa9\x01\u00c1\xaa\x01\u00c1\xab\x01\u00c1\xac\x01\u00c1\xad\x01\u00c1\xae\x01\u00c1\xaf\x01\u00c1\xb0\x01\u00c1\xb1\x01\u00c1\xb2\x01\u00c1\xb3\x01\u00c1\xb4\x01\u00c1\xb5\x01\u00c1\xb6\x01\u00c1\xb7\x01\u00c1\xb8\x01\u00c1\xb9\x01\u00c1\xba\x01\u00c1\xbb\x01\u00c1\xbc\x01\u00c1\xbd\x01\u00c1\xbe\x01\u00c1\xbf\x01\u00c1\xc0\x01\u00c1\xc1\x01\u00c1\xc2\x01\u00c1\xc3\x01\u00c1\xc4\x01\u00c1\xc5\x01\u00c1\xc6\x01\u00c1\xc7\x01\u00c1\xc8\x01\u00c1\xc9\x01\u00c1\xca\x01\u00c1\xcb\x01\u00c1\xcc\x01\u00c1\xcd\x01\u00c1\xce\x01\u00c1\xcf\x01\u00c1\xd0\x01\u00c1\xd1\x01\u00c1\xd2\x01\u00c1\xd3\x01\u00c1\xd4\x01\u00c1\xd5\x01\u00c1\xd6\x01\u00c1\xd7\x01\u00c1\xd8\x01\u00c1\xd9\x01\u00c1\xda\x01\u00c1\xdb\x01\u00c1\xdc\x01\u00c1\xdd\x01\u00c1\xde\x01\u00c1\xdf\x01\u00c1\xe0\x01\u00c1\xe1\x01\u00c1\xe2\x01\u00c1\xe3\x01\u00c1\xe4\x01\u00c1\xe5\x01\u00c1\xe6\x01\u00c1\xe7\x01\u00c1\xe8\x01\u00c1\xe9\x01\u00c1\xea\x01\u00c1\xeb\x01\u00c1\xec\x01\u00c1\xed\x01\u00c1\xee\x01\u00c1\xef\x01\u00c1\xf0\x01\u00c1\xf1\x01\u00c1\xf2\x01\u00c1\xf3\x01\u00c1\xf4\x01\u00c1\xf5\x01\u00c1\xf6\x01\u00c1\xf7\x01\u00c1\xf8\x01\u00c1\xf9\x01\u00c1\xfa\x01\u00c1\xfb\x01\u00c1\xfc\x01\u00c1\xfd\x01\u00c1\xfe\x01\u00c1\xff\x01\xf6\x94\x8a7\x86o\xd3b|\x92\x05\xa3|\x86\x85fo2\xec\a\xbb\x1b\xa0\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index 0c8a3bc850..70621ccbc0 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -78,9 +78,9 @@ var PrecompiledContractsIstanbul = map[common.Address]PrecompiledContract{
 	common.BytesToAddress([]byte{9}): &blake2F{},
 }
 
-// PrecompiledContractsBerlin contains the default set of pre-compiled Ethereum
-// contracts used in the Berlin release.
-var PrecompiledContractsBerlin = map[common.Address]PrecompiledContract{
+// PrecompiledContractsYoloV1 contains the default set of pre-compiled Ethereum
+// contracts used in the Yolo v1 test release.
+var PrecompiledContractsYoloV1 = map[common.Address]PrecompiledContract{
 	common.BytesToAddress([]byte{1}):  &ecrecover{},
 	common.BytesToAddress([]byte{2}):  &sha256hash{},
 	common.BytesToAddress([]byte{3}):  &ripemd160hash{},
diff --git a/core/vm/contracts_test.go b/core/vm/contracts_test.go
index a0da3f02af..139de99e54 100644
--- a/core/vm/contracts_test.go
+++ b/core/vm/contracts_test.go
@@ -42,7 +42,7 @@ type precompiledFailureTest struct {
 	Name          string
 }
 
-var allPrecompiles = PrecompiledContractsBerlin
+var allPrecompiles = PrecompiledContractsYoloV1
 
 // EIP-152 test vectors
 var blake2FMalformedInputTests = []precompiledFailureTest{
diff --git a/core/vm/evm.go b/core/vm/evm.go
index c86da054db..63fe652b67 100644
--- a/core/vm/evm.go
+++ b/core/vm/evm.go
@@ -51,6 +51,9 @@ func run(evm *EVM, contract *Contract, input []byte, readOnly bool) ([]byte, err
 		if evm.chainRules.IsIstanbul {
 			precompiles = PrecompiledContractsIstanbul
 		}
+		if evm.chainRules.IsYoloV1 {
+			precompiles = PrecompiledContractsYoloV1
+		}
 		if p := precompiles[*contract.CodeAddr]; p != nil {
 			return RunPrecompiledContract(p, input, contract)
 		}
diff --git a/core/vm/interpreter.go b/core/vm/interpreter.go
index 4a96f1431b..4bbab51337 100644
--- a/core/vm/interpreter.go
+++ b/core/vm/interpreter.go
@@ -101,6 +101,8 @@ func NewEVMInterpreter(evm *EVM, cfg Config) *EVMInterpreter {
 	if !cfg.JumpTable[STOP].valid {
 		var jt JumpTable
 		switch {
+		case evm.chainRules.IsYoloV1:
+			jt = yoloV1InstructionSet
 		case evm.chainRules.IsIstanbul:
 			jt = istanbulInstructionSet
 		case evm.chainRules.IsConstantinople:
diff --git a/core/vm/jump_table.go b/core/vm/jump_table.go
index 23decaa7b9..f7e5f45a27 100644
--- a/core/vm/jump_table.go
+++ b/core/vm/jump_table.go
@@ -57,11 +57,20 @@ var (
 	byzantiumInstructionSet        = newByzantiumInstructionSet()
 	constantinopleInstructionSet   = newConstantinopleInstructionSet()
 	istanbulInstructionSet         = newIstanbulInstructionSet()
+	yoloV1InstructionSet           = newYoloV1InstructionSet()
 )
 
 // JumpTable contains the EVM opcodes supported at a given fork.
 type JumpTable [256]operation
 
+func newYoloV1InstructionSet() JumpTable {
+	instructionSet := newIstanbulInstructionSet()
+
+	enable2315(&instructionSet) // Subroutines - https://eips.ethereum.org/EIPS/eip-2315
+
+	return instructionSet
+}
+
 // newIstanbulInstructionSet returns the frontier, homestead
 // byzantium, contantinople and petersburg instructions.
 func newIstanbulInstructionSet() JumpTable {
diff --git a/params/bootnodes.go b/params/bootnodes.go
index e1898d7624..c8736b8ae8 100644
--- a/params/bootnodes.go
+++ b/params/bootnodes.go
@@ -63,6 +63,12 @@ var GoerliBootnodes = []string{
 	"enode://a61215641fb8714a373c80edbfa0ea8878243193f57c96eeb44d0bc019ef295abd4e044fd619bfc4c59731a73fb79afe84e9ab6da0c743ceb479cbb6d263fa91@3.11.147.67:30303",
 }
 
+// YoloV1Bootnodes are the enode URLs of the P2P bootstrap nodes running on the
+// YOLOv1 ephemeral test network.
+var YoloV1Bootnodes = []string{
+	"enode://9e1096aa59862a6f164994cb5cb16f5124d6c992cdbf4535ff7dea43ea1512afe5448dca9df1b7ab0726129603f1a3336b631e4d7a1a44c94daddd03241587f9@35.178.210.161:30303",
+}
+
 const dnsPrefix = "enrtree://AKA3AM6LPBYEUDMVNU3BSVQJ5AD45Y7YPOHJLEF6W26QOE4VTUDPE@"
 
 // KnownDNSNetwork returns the address of a public DNS-based node list for the given
diff --git a/params/config.go b/params/config.go
index 6d830e42ce..3a78ad685c 100644
--- a/params/config.go
+++ b/params/config.go
@@ -31,6 +31,7 @@ var (
 	RopstenGenesisHash = common.HexToHash("0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d")
 	RinkebyGenesisHash = common.HexToHash("0x6341fd3daf94b748c72ced5a5b26028f2474f5f00d824504e4fa37a75767e177")
 	GoerliGenesisHash  = common.HexToHash("0xbf7e331f7f7c1dd2e05159666b3bf8bc7a8a3a9eb1d518969eab529dd9b88c1a")
+	YoloV1GenesisHash  = common.HexToHash("0xc3fd235071f24f93865b0850bd2a2119b30f7224d18a0e34c7bbf549ad7e3d36")
 )
 
 // TrustedCheckpoints associates each known checkpoint with the genesis hash of
@@ -144,6 +145,7 @@ var (
 		ConstantinopleBlock: big.NewInt(3660663),
 		PetersburgBlock:     big.NewInt(4321234),
 		IstanbulBlock:       big.NewInt(5435345),
+		MuirGlacierBlock:    nil,
 		Clique: &CliqueConfig{
 			Period: 15,
 			Epoch:  30000,
@@ -183,6 +185,7 @@ var (
 		ConstantinopleBlock: big.NewInt(0),
 		PetersburgBlock:     big.NewInt(0),
 		IstanbulBlock:       big.NewInt(1561651),
+		MuirGlacierBlock:    nil,
 		Clique: &CliqueConfig{
 			Period: 15,
 			Epoch:  30000,
@@ -210,21 +213,42 @@ var (
 		Threshold: 2,
 	}
 
+	// YoloV1ChainConfig contains the chain parameters to run a node on the YOLOv1 test network.
+	YoloV1ChainConfig = &ChainConfig{
+		ChainID:             big.NewInt(133519467574833),
+		HomesteadBlock:      big.NewInt(0),
+		DAOForkBlock:        nil,
+		DAOForkSupport:      true,
+		EIP150Block:         big.NewInt(0),
+		EIP155Block:         big.NewInt(0),
+		EIP158Block:         big.NewInt(0),
+		ByzantiumBlock:      big.NewInt(0),
+		ConstantinopleBlock: big.NewInt(0),
+		PetersburgBlock:     big.NewInt(0),
+		IstanbulBlock:       big.NewInt(0),
+		MuirGlacierBlock:    nil,
+		YoloV1Block:         big.NewInt(0),
+		Clique: &CliqueConfig{
+			Period: 15,
+			Epoch:  30000,
+		},
+	}
+
 	// AllEthashProtocolChanges contains every protocol change (EIPs) introduced
 	// and accepted by the Ethereum core developers into the Ethash consensus.
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, new(EthashConfig), nil}
 
 	// AllCliqueProtocolChanges contains every protocol change (EIPs) introduced
 	// and accepted by the Ethereum core developers into the Clique consensus.
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
+	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
 
-	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, new(EthashConfig), nil}
 	TestRules       = TestChainConfig.Rules(new(big.Int))
 )
 
@@ -295,7 +319,9 @@ type ChainConfig struct {
 	PetersburgBlock     *big.Int `json:"petersburgBlock,omitempty"`     // Petersburg switch block (nil = same as Constantinople)
 	IstanbulBlock       *big.Int `json:"istanbulBlock,omitempty"`       // Istanbul switch block (nil = no fork, 0 = already on istanbul)
 	MuirGlacierBlock    *big.Int `json:"muirGlacierBlock,omitempty"`    // Eip-2384 (bomb delay) switch block (nil = no fork, 0 = already activated)
-	EWASMBlock          *big.Int `json:"ewasmBlock,omitempty"`          // EWASM switch block (nil = no fork, 0 = already activated)
+
+	YoloV1Block *big.Int `json:"yoloV1Block,omitempty"` // YOLO v1: https://github.com/ethereum/EIPs/pull/2657 (Ephemeral testnet)
+	EWASMBlock  *big.Int `json:"ewasmBlock,omitempty"`  // EWASM switch block (nil = no fork, 0 = already activated)
 
 	// Various consensus engines
 	Ethash *EthashConfig `json:"ethash,omitempty"`
@@ -332,7 +358,7 @@ func (c *ChainConfig) String() string {
 	default:
 		engine = "unknown"
 	}
-	return fmt.Sprintf("{ChainID: %v Homestead: %v DAO: %v DAOSupport: %v EIP150: %v EIP155: %v EIP158: %v Byzantium: %v Constantinople: %v Petersburg: %v Istanbul: %v, Muir Glacier: %v, Engine: %v}",
+	return fmt.Sprintf("{ChainID: %v Homestead: %v DAO: %v DAOSupport: %v EIP150: %v EIP155: %v EIP158: %v Byzantium: %v Constantinople: %v Petersburg: %v Istanbul: %v, Muir Glacier: %v, YOLO v1: %v, Engine: %v}",
 		c.ChainID,
 		c.HomesteadBlock,
 		c.DAOForkBlock,
@@ -345,6 +371,7 @@ func (c *ChainConfig) String() string {
 		c.PetersburgBlock,
 		c.IstanbulBlock,
 		c.MuirGlacierBlock,
+		c.YoloV1Block,
 		engine,
 	)
 }
@@ -401,6 +428,11 @@ func (c *ChainConfig) IsIstanbul(num *big.Int) bool {
 	return isForked(c.IstanbulBlock, num)
 }
 
+// IsYoloV1 returns whether num is either equal to the YoloV1 fork block or greater.
+func (c *ChainConfig) IsYoloV1(num *big.Int) bool {
+	return isForked(c.YoloV1Block, num)
+}
+
 // IsEWASM returns whether num represents a block number after the EWASM fork
 func (c *ChainConfig) IsEWASM(num *big.Int) bool {
 	return isForked(c.EWASMBlock, num)
@@ -428,20 +460,23 @@ func (c *ChainConfig) CheckCompatible(newcfg *ChainConfig, height uint64) *Confi
 // to guarantee that forks can be implemented in a different order than on official networks
 func (c *ChainConfig) CheckConfigForkOrder() error {
 	type fork struct {
-		name  string
-		block *big.Int
+		name     string
+		block    *big.Int
+		optional bool // if true, the fork may be nil and next fork is still allowed
 	}
 	var lastFork fork
 	for _, cur := range []fork{
-		{"homesteadBlock", c.HomesteadBlock},
-		{"eip150Block", c.EIP150Block},
-		{"eip155Block", c.EIP155Block},
-		{"eip158Block", c.EIP158Block},
-		{"byzantiumBlock", c.ByzantiumBlock},
-		{"constantinopleBlock", c.ConstantinopleBlock},
-		{"petersburgBlock", c.PetersburgBlock},
-		{"istanbulBlock", c.IstanbulBlock},
-		{"muirGlacierBlock", c.MuirGlacierBlock},
+		{name: "homesteadBlock", block: c.HomesteadBlock},
+		{name: "daoForkBlock", block: c.DAOForkBlock, optional: true},
+		{name: "eip150Block", block: c.EIP150Block},
+		{name: "eip155Block", block: c.EIP155Block},
+		{name: "eip158Block", block: c.EIP158Block},
+		{name: "byzantiumBlock", block: c.ByzantiumBlock},
+		{name: "constantinopleBlock", block: c.ConstantinopleBlock},
+		{name: "petersburgBlock", block: c.PetersburgBlock},
+		{name: "istanbulBlock", block: c.IstanbulBlock},
+		{name: "muirGlacierBlock", block: c.MuirGlacierBlock, optional: true},
+		{name: "yoloV1Block", block: c.YoloV1Block},
 	} {
 		if lastFork.name != "" {
 			// Next one must be higher number
@@ -456,7 +491,10 @@ func (c *ChainConfig) CheckConfigForkOrder() error {
 				}
 			}
 		}
-		lastFork = cur
+		// If it was optional and not set, then ignore it
+		if !cur.optional || cur.block != nil {
+			lastFork = cur
+		}
 	}
 	return nil
 }
@@ -498,6 +536,9 @@ func (c *ChainConfig) checkCompatible(newcfg *ChainConfig, head *big.Int) *Confi
 	if isForkIncompatible(c.MuirGlacierBlock, newcfg.MuirGlacierBlock, head) {
 		return newCompatError("Muir Glacier fork block", c.MuirGlacierBlock, newcfg.MuirGlacierBlock)
 	}
+	if isForkIncompatible(c.YoloV1Block, newcfg.YoloV1Block, head) {
+		return newCompatError("YOLOv1 fork block", c.YoloV1Block, newcfg.YoloV1Block)
+	}
 	if isForkIncompatible(c.EWASMBlock, newcfg.EWASMBlock, head) {
 		return newCompatError("ewasm fork block", c.EWASMBlock, newcfg.EWASMBlock)
 	}
@@ -568,6 +609,7 @@ type Rules struct {
 	ChainID                                                 *big.Int
 	IsHomestead, IsEIP150, IsEIP155, IsEIP158               bool
 	IsByzantium, IsConstantinople, IsPetersburg, IsIstanbul bool
+	IsYoloV1                                                bool
 }
 
 // Rules ensures c's ChainID is not nil.
@@ -586,5 +628,6 @@ func (c *ChainConfig) Rules(num *big.Int) Rules {
 		IsConstantinople: c.IsConstantinople(num),
 		IsPetersburg:     c.IsPetersburg(num),
 		IsIstanbul:       c.IsIstanbul(num),
+		IsYoloV1:         c.IsYoloV1(num),
 	}
 }
diff --git a/tests/init.go b/tests/init.go
index a18e12bdd2..70382d3562 100644
--- a/tests/init.go
+++ b/tests/init.go
@@ -140,6 +140,18 @@ var Forks = map[string]*params.ChainConfig{
 		PetersburgBlock:     big.NewInt(0),
 		IstanbulBlock:       big.NewInt(5),
 	},
+	"YOLOv1": {
+		ChainID:             big.NewInt(1),
+		HomesteadBlock:      big.NewInt(0),
+		EIP150Block:         big.NewInt(0),
+		EIP155Block:         big.NewInt(0),
+		EIP158Block:         big.NewInt(0),
+		ByzantiumBlock:      big.NewInt(0),
+		ConstantinopleBlock: big.NewInt(0),
+		PetersburgBlock:     big.NewInt(0),
+		IstanbulBlock:       big.NewInt(0),
+		YoloV1Block:         big.NewInt(0),
+	},
 }
 
 // UnsupportedForkError is returned when a test requests a fork that isn't implemented.