Developed by Vietnam-based game studio Sky Mavis, Axie Infinity is a blockchain-based play-to-earn game built on the Ronin network, an Ethereum sidechain. Players buy, train, breed, and battle pets called Axies, available in the form of NFTs to earn the in-game currency SLP. Axie Infinity players can also sell their Axies in the marketplace to earn real money. Players need three Axies to get started, the cost of which fluctuated overtime, which in turn has created a barrier to entry.