According to Wu Shuo, significant progress has been made in the development of the Bitcoin ecological layer, especially in L2 solutions. The Bitcoin ecosystem has expanded to include Sidechains, Drivechains, Merge-Mined Chains, and Proof-of-Stake Chains. At the same time, we have also witnessed the emergence of multiple protocols, token standards, cross-chain bridges, Rollups, and other innovative solutions. This article details key innovations in these categories, demonstrating the dynamic and forward-looking nature of Bitcoin’s layered ecosystem.