Mortar
From Warhammer - The Old World - Lexicanum
The Empire Mortar is part of the Empire Army List. They are shorter and heavier than Great Cannons and are designed to lob a shell to fall upon the target rather than directly firing at it. The shell is hollow and full of gunpowder and the crew light the fuse before loading the mortar. While a cannon may rip through ranks and kill three or four warriors, an exploding mortar shell can spray mud and pieces of shell over a large area, shredding many victims at once.
Empire Mortars may be taken as a Special choice.
