Minecraft - A block-building game that allows you to create and explore entire worlds from scratch.
EVE Online - Player-created empires, player-driven markets, and endless ways to embark on your personal sci-fi adventure.
Terraria - Dig, Fight, Build! The very world is at your fingertips as you fight for survival, fortune, and glory.
Star Conflict - Star Conflict is a free MMO action game and space simulator that was introduced in 2012.
Minetest - Minetest is a near-infinite-world block sandbox game and a game engine, inspired by InfiniMiner...
Star Trek Online - Star Trek Online (STO) is a free to play MMORPG that takes place inside the Star Trek world.