MyWorldGen Mod 1.8, 1.7.10, 1.7.2 revolutionizes Minecraft world generation. Rather than introducing new biomes, or trying to make up strange-looking hard-coded structures, MyWorldGen relies on you to populate your world. All you have to do is put some schematic files into your .minecraft/worldgen folder, and they'll start showing up in your single-player worlds. You can also install it onto a server, and have custom worldgen for your own community!