Karst Mainnet Upgrade
Ronin (RON) · Releases & Updates · October 7, 2026
Ronin's Karst upgrade activates on mainnet October 7, 2026 at 16:00 UTC, bringing Ethereum's Fusaka changes to the Ronin L2.
Ronin, the gaming-focused Ethereum layer-2 behind Axie Infinity, activates the Karst network upgrade on mainnet on October 7, 2026 at 16:00:01 UTC. Karst brings Ronin in line with Ethereum's Fusaka hard fork: latest execution-layer improvements, a new L2 Contract Manager that lets Ronin upgrade core contracts in a single block, and L1 contracts moved to op-contracts v7.0.0. Builders should note a new per-transaction gas cap of about 16.8M, pricier P256VERIFY and MODEXP precompiles, a lower bn256Pairing limit (300 pairs) and the new CLZ opcode. No action for RON holders and no downtime; node operators must upgrade op-node, move to op-reth v2.2.3 and refresh genesis files, or stop following the chain. Karst has run on the Saigon testnet since September 2.