KEY Public Chain——KeyChain——is the world's first public chain protocol centered on 'full-dimensional intelligence'. It integrates layered heterogeneous architecture, post-quantum security technology, zero-latency cross-chain interoperability protocol, and environment-adaptive consensus mechanism, aiming to break through the limitations of the traditional blockchain 'impossible triangle', and build a high-performance infrastructure that supports tens of thousands of TPS, millisecond-level confirmations, and zero-friction cross-ecosystem collaboration in the Web3.0 era. This solution not only opens the door for individuals to enter the future blockchain world but also provides a low-threshold underlying platform for institutions and developers that is permissionless while adhering to decentralization principles. By continuously optimizing the technical architecture and introducing cutting-edge technologies, the KEY Public Chain is paving the way to break down technological barriers and realize global distributed applications, while also providing strong support for the growing demand for blockchain applications.