Minetest is a near-infinite-world block sandbox game and a game engine, inspired by InfiniMiner, Minecraft, and the like.
Minetest is available natively for Windows, OS X, GNU/Linux, Android, and FreeBSD. It is Free/Libre and Open Source Software, released under the LGPL 2.1 or later.
With a 620003 block playing area, there's no running out of space. Yes, the world height is also near-infinite.
Play by yourself, locally with your friends, or online with dozens of players on a server.
Want to install dozens of mods at once? You can. Want to play Hunger Games? No problem!
Not happy at the look of the textures? Change the textures!
Beautiful map generators
Choose from several different in-house map generators, v5, v6, v7, flat, fractal, and valleys, each of them featuring several biomes.