War machines are important part of many armies in the Warhammer world. Amongst the most spectacular of these engines of destruction are the mighty cannons of the Empire and the Dwarfs, but their manufacture is difficult and the secrets of gun casting and black-powder manufacture are carefully guarded. Other races build gigantic stone throwers that lob boulders high into the air to come crashing down upon enemy formations or behind city walls. Bolt throwers are giant crossbows that can send a spear-sized bolt clean through several ranks of enemy, skewering each in turn. These are all relatively common war machines that can be found in several armies, and thus their rules are included here. Many other weird and unique war machines are described in the Warhammer Armies books, like the infamous Skaven Warp-lightning Cannon and the wacky Goblin Doom Diver. Their rules are included in the appropriate book.