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Metis is in the rollup battlefield, and generally speaking, rollups are solutions that perform transaction execution outside the main. mainnet (layer 1), while taking advantage of the robust decentralized security model of mainnet. Metis introduces a Ranger’s system to incentivize the fast validators with Metis token mining rewards to solve the problem of long validation time, leveraging economic ways to speed up the transaction validation time. Layer 2 refers to a wide range of scaling solutions(rollups, validium, plasma, state channels, etc.) designed to help scale your application.