Etheria is a decentralized 3D virtual world of unique hexagonal water and land tiles, created and deployed to the Ethereum blockchain in October 2015. Its provably scarce land tiles can be owned, transferred, and customized with voxel-based sculptures, and its entire world state, including ownership and build data, is stored natively on-chain. Etheria cannot be altered against its owners' will or destroyed, not even by its creator, and will persist as long as Ethereum does.