Lizardmen designed a specialized catapult to be strapped to the backs of giant turtles. This modification allows for easy transport through the treacherous swamps in which the Lizardmen often dwell, seeing as how horses and other beasts of burden were not nearly as mobile and far too edible in the swamp.
Like normal catapults, these constructions are primarily used in sieges to breach a city's outer wall. The huge boulders hurled by these machines are ideal for such attacks. However, they are occasionally employed, with less accuracy, to attack individual units. If a catapult's stone does find its target, the damage caused is devastating to almost any creature.