Immutable Chain Will Switch to Optimism’s OP Stack in Mid-2027: Faster Blocks, Seven-Day Withdrawals and a Testnet Shutdown - eGamers.io

Immutable Chain, which hosts games including Gods Unchained and Guild of Guardians, is undergoing a significant rebuild. The company plans to move the network onto the OP Stack, the open-source framework from Optimism, transforming it into a standard Ethereum rollup. This migration is scheduled for completion in mid-2027.

Faster blocks, higher fees

According to Immutable, block times will be reduced from approximately two seconds to just one second, allowing for quicker confirmations of onchain actions in games. However, the cost per transaction is expected to increase slightly following the migration. While the network currently offers cheap transactions, the actual fee increase will depend on network activity after the switch.

New withdrawal rules

The current chain relies on Axelar for native bridging. After moving to the OP Stack, withdrawals will be verified directly against Ethereum using cryptographic proofs, with Ethereum also handling data availability. Initially, the network will use permissioned fault proofs, with zero-knowledge validity proofs planned for a later stage. Importantly, native withdrawals from the upgraded chain will take about seven days.

Migration impact on developers

The public gaming testnet will be shut down by the end of 2026, as Immutable states it couldn't mirror real-world conditions for complex games due to cheap gas and limited third-party integrations. Developers and infrastructure providers will need to review migration documentation and update their setups. The exact migration date will be announced in advance, with block production expected to pause for several hours during the transition.

Game experience changes

Games like Gods Unchained and Guild of Guardians will benefit from a more standard foundation for development and maintenance. The trade-off offers one-second blocks and Ethereum-verified withdrawals in exchange for slightly higher fees and a seven-day withdrawal period. This migration doesn't inherently make games more profitable but provides a more robust infrastructure for studios building on the network.