From BlockchainGaming Wiki

ERC-20 is a standardized smart contract format for generating cryptocurrency and utility tokens on Ethereum, designed internally by their team. Many major blockchain gaming tokens use it, including those for Enjin, Decentraland, GameCredits, the Sandbox, and Axie Infinity. It has even been ported to other blockchains such as Ubiq, where it is used by blockchain game GeoCoin.