Frontier
GenesisBlock 1
2015-07-30
Ethereum Classic genesis. The original Ethereum codebase launches — the first production EVM with smart contract capability. The ledger begins.
Frontier Thawing
EVM ParityBlock 200,000
2015-09-07
Gas limit raised from 5,000 to allow network growth. Mining difficulty threshold adjusted.
ETH DAO Fork
/ Rejected by Ethereum ClassicDefining MomentBlock 1,920,000
2016-07-20
Ethereum implemented an irregular state change to reverse the DAO exploit. Ethereum Classic rejected this intervention, upholding Code is Law and the immutability of the ledger. ETC and ETH permanently diverge. This is the founding principle of Ethereum Classic.
Gas Reprice
/ Tangerine WhistleEVM ParityBlock 2,500,000
2016-10-24
Gas cost repricing for IO-heavy operations to prevent denial-of-service attacks that had been exploiting underpriced opcodes.
Die Hard
/ Spurious DragonETC NativeEVM ParityBlock 3,000,000
2017-01-13
Delayed the difficulty bomb and implemented replay protection via chain ID. ETC's first independent protocol deviation from Ethereum.
Gotham
/ 5M20 Monetary PolicyMonetary PolicyETC NativeBlock 5,000,000
2017-12-11
Established ETC's fixed monetary policy: the 5M20 era system with a 210,700,000 maximum supply. Block rewards reduce 20% every 5,000,000 blocks — sound, predictable, immutable.
Defuse Difficulty Bomb
ETC NativeBlock 5,900,000
2018-05-29
Permanently removed the difficulty bomb from ETC, ensuring the Proof-of-Work chain continues in perpetuity without artificial pressure to migrate.
Atlantis
/ ByzantiumEVM ParityBlock 8,772,000
2019-09-12
Byzantium parity. Added precompiles for elliptic curve arithmetic enabling ZK-proof compatibility, REVERT opcode, and receipt status codes.
Agharta
/ Constantinople + PetersburgEVM ParityBlock 9,583,000
2020-01-11
Constantinople and Petersburg parity. Introduced bitwise shifting opcodes, CREATE2 for deterministic contract deployment, and EXTCODEHASH.
Phoenix
/ IstanbulEVM ParityBlock 10,500,839
2020-06-01
Istanbul parity. Added BLAKE2 precompile, repriced elliptic curve operations, chain ID opcode, and improved gas cost accuracy for storage operations.
Thanos
/ ETCHash + MESSETC NativeBlock 11,700,000
2020-11-28
Introduced ETCHash — a modified DAG growth algorithm keeping ETC mineable on GPU hardware — and MESS (Modified Exponential Subjective Scoring) for chain finality. Following Ethereum's Merge, ETC absorbed a significant portion of the global GPU mining network.
Magneto
/ BerlinEVM ParityBlock 13,189,133
2021-07-23
Berlin parity. Repriced cold storage access operations, introduced typed transaction envelopes, and added optional access lists for gas optimization.
Mystique
/ London (partial)EVM ParityBlock 14,525,000
2022-02-12
London parity without EIP-1559. Reduced gas refunds, reserved the 0xEF bytecode prefix for future use. The fee market upgrade arrives with Olympia.
Spiral
/ ShanghaiEVM ParityBlock 19,250,000
2024-02-04
Shanghai parity. Warm COINBASE access, PUSH0 opcode, initcode size limit. The most recently completed ETC network upgrade.
Olympia
/ Fusaka + EIP-1559 + DAO GovernanceUpcomingETC NativeEVM ParityPending Activation Block
Before 2027
ETC's most significant upgrade — EVM alignment to Fusaka, incorporating EIPs spanning London, Dencun, Pectra, and Fusaka. Introduces EIP-1559 fee market with basefee directed to a protocol treasury and on-chain DAO governance.