Minetest - Minetest is a near-infinite-world block sandbox game and a game engine, inspired by InfiniMiner...
Creativerse - Creativerse is a sandbox adventure game set in a beautiful yet treacherous world shrouded in...
Minecraft - A block-building game that allows you to create and explore entire worlds from scratch.
Deepworld - Deepworld is a massively-multiplayer 2D crafting adventure game.
Terasology - Terasology (started under the name Blockmania) is an open source project started by Benjamin...
Voxelands - The Fun-Focused Free Software Voxel World Game.