ExRelay is a network of Ethereum sidechain settlement relayers, based on Ethereum asset settlement. It facilitates high-frequency, low-cost, and efficient settlement of various asset transactions in the Ethereum world, while maintaining full decentralization, and sharing a global order book. The ExRelay network will introduce a significant amount of complex matching trade computing power to the ExRelay network, ensuring that trades are conducted under complete decentralization of Ethereum assets. Any DApp within the Ethereum ecosystem can connect to the ExRelay network and use market-driven behavior to solve its own DeFi business settlement issues. This enables instant listing, cancellation, and trading, with no deposits or withdrawals and no asset mapping, as all assets are genuine. While most ExRelay transactions still require confirmation within the Ethereum world, for small transactions, ExRelay will implement a new confirmation mechanism, adopting the Lightning Networks approach for early confirmation, and establishing a fund protection mechanism to safeguard against any risks. ExRelay is an infrastructural technology designed to facilitate the practical implementation of DApps. All underlying designs are aimed at ensuring low-threshold implementation of the DApp ecosystem. With the advent of Ethereum 2.0, ExRelay holds immense potential for the future.