Ethereum's Fusaka upgrade has been successfully activated on the Sepolia testnet, marking a significant milestone in the network's scalability and performance enhancement efforts. This activation represents the second phase of the Fusaka roadmap, following the Holesky testnet activation earlier this month. The Sepolia deployment is designed to stress test the network's new data-availability system and increased block gas limit, setting the stage for the final Hoodi testnet activation later this month. The Fusaka upgrade aims to increase Ethereum's block gas limit to 60 million, enabling more transactions and complex smart contracts per block. Key features being tested include Peer Data Availability Sampling (PeerDAS), which allows validators to verify transaction data more efficiently, reducing the burden on nodes. The mainnet launch of Fusaka is anticipated in December, following the final test on the Hoodi testnet scheduled for October 28.