Xackery

Blade your reply worked, just note with 1.7.1+ you need to do some changes as per : http://www.wuppy29.com/minecraft/modding-tutorials/wuppys-minecraft-forge-modding-tutorials-for-1-7-updating-1-6-to-1-7-part-1-modfile-and-recipes/#sthash.9BCseiYx.dpbs Basically, biomeList becomes getBiomeGenArray() as well as getIntTemperature() changes to getFloatTemperature() with additional parameters. As per original answer, I managed to get multiple biomes on a custom dimension with modding ChunkProvider, WorldProvider, WorldChunkManager