Immutable Chain, which hosts games including Gods Unchained GODS $0.01965 ▼ -5% (official site) and Guild of Guardians (official site), is getting rebuilt. Immutable plans to move the network onto the OP Stack, the open-source framework from Optimism, which makes it a standard Ethereum rollup. The company is aiming to finish the migration in mid-2027.
For players, blocks will come faster, fees will go up slightly and native withdrawals will take seven days. Developers lose the public gaming testnet before any of those changes land.
Block times halve, fees edge up
According to Immutable, block times will fall from roughly two seconds to one second. Onchain actions in games on the network should confirm more quickly as a result.
The cost per transaction is expected to rise a little. Immutable says fees should go up slightly once the migration is done. Transactions on the network are currently cheap, and the actual size of any fee change will depend on how busy the network is after the switch.
New rules for bridging and withdrawals
The chain currently relies on Axelar for native bridging. Once it moves to the OP Stack, withdrawals will be checked directly against Ethereum using cryptographic proofs, and Ethereum will also handle data availability.
At launch the network will use permissioned fault proofs. Zero-knowledge validity proofs are planned for a later stage.
If you move assets between networks, plan around this: native withdrawals from the upgraded chain are expected to take about seven days.
The reason for the switch
Today Immutable Chain runs on a heavily modified build of Go-Ethereum (Geth). A custom build means each major Ethereum upgrade, security patch and protocol change has to be merged in manually. Immutable says the OP Stack puts the network closer to Ethereum’s standard infrastructure, which makes future upgrades easier to ship, improves compatibility and reduces the effort of maintaining a separate blockchain implementation.
The testnet closes, and migration day will pause the chain
The public gaming testnet will be shut down by the end of 2026. The announcement says gas on the testnet was so cheap, and third-party integrations so limited, that it could not mirror real-world conditions for complex games. Immutable is directing studios to run their own local test environments, or to use the production network where that fits.
Developers and infrastructure providers need to go through Immutable’s migration documentation and update their setups. Immutable says the exact migration date will be announced ahead of time, and block production is expected to stop for several hours while the switch happens.
What changes for Immutable’s games
Games on Immutable are available on PC and mobile. Gods Unchained is a free-to-play trading card game in which you build decks, play strategic matches and collect cards that exist as NFTs. Guild of Guardians GOG $0.0008123 ▼ -3.1% is a mobile fantasy action RPG: you assemble teams of Guardians, run dungeons, collect resources and level up your characters. RPGs, strategy games and collectible titles from other studios also run on the network.
Moving to the OP Stack gives these studios a more standard foundation for building and maintaining their games. It does not make any game more profitable or increase anyone’s rewards, and studios still need games that attract players and keep them around. The trade-off is one-second blocks and Ethereum-verified withdrawals in exchange for slightly higher fees and a seven-day native withdrawal period. How that works out for players will become clear once the migration wraps up in 2027.