Mercenary Catapults

Though generally considered somewhat primitive and backwards by today's standards, there is no denying that the tried-and-true catapult is a cheap and good weapon. That is why the Carrion Kings field them as their standard artillery pieces. Catapults are cheap and easy to build and simple to train crews in the use of, making them ideal for the money-centric Carrionites. 
In sieges and open battle, it is common to see these catapults using flaming ammunition. This might seem quite strange but is actually quite smart, as it is a form of deep psychological warfare. Not only does the flames risk spreading fires, but the heat of the fire intensifies the already immense heat of the desert. Most would not be able to deal with such an environment and so be more likely to break and flee. In this way, these primitive weapons utilise the environment to their advantage, making an already good weapon even more effective. As well as flaming projectiles, these catapults also utilise simple rock ammunition for blunt-force power as well as clay pots filled with flammable oil.