War machines are an important part of many armies in the Warhammer World. Gigantic cannons are amongst the most spectacular of these engines of war, but their manufacture is difficult and the secrets of gun casting and gunpowder manufacture are carefully guarded. Orcs and other less sophisticated races build gigantic stone throwers which lob boulders high into the air to come crashing down upon enemy formations or behind city walls. Bolt throwers are powerful 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.