Sand Serpents

Sand Serpents are giant snake-like creatures that live in the most remote parts of the Dead Sands. It is believed that Sand Serpents are relatives of the Sea Serpent, though totally opposite in direction. Where Sea Serpents lie in wait below the waves, Sand Serpents lie in wait below the dunes. Being reptilian in nature, these serpents can go months without feeding. But, when food does reveal itself, the Sand Serpent will erupt from the ground to launch a devastating attack. From there the serpent can impale its prey on their spear-like fangs, strangle them in a deathly coil, or simply swallow them whole in smaller cases. When necessary, the Sand Serpent can even spit an acidic venom that burns and melts the flesh of whatever it hits. If a purely physical approach is somehow not enough, this venom more often than not does the trick. 
With all this in mind, it makes perfect sense as to why the Carrion Kingdoms are desperate for these creatures. Surprisingly, Sand Serpents are fairly complacent if they are fed every so often, making taming and maintenance a fairly simple process. In war, Sand Serpents are devastatingly effective predators. With their size they can crush groups of infantry. With their fangs they can impale and slay war beasts and cavalry. And with their venom they can dissolve groups into little more than a grotesque bloody mush - a puddle to be swallowed up by the dry sand. In some cases, Sand Serpents are even used as mounts for experienced soldiers, riding into battle as their own units. However, this is an incredibly complex process and so is more uncommon when compared the using of independent serpents.