Dungeons are small rooms made of cobblestone and moss stone and contain a monster spawner and up to 2 chests. Finding a dungeon without a chest is very unlikely, but possible. Occasionally, a dungeon will spawn with its chests in such a way as to create a double chest. Dungeons generate with either a zombie (50% chance), skeleton (25% chance), or spider (25% chance) spawner. The spawner is always in the center of the dungeon room, with chests located around the walls of the room (large chests can connect with the short side against the wall) Each block of the floor has a 25% chance of being cobblestone, and a 75% chance of being moss stone. Dungeons will still generate if the 'generate structures' option is toggled to off.