The Haetae is a legendary creature which resembles a lion, but is, in fact, a fire-eating dog.
Upon being spawned it will take a defensive posture and can be mounted. The Haetae is slow moving, but its ability to eat fire (has to be woken up after three uses) is invaluable. It protects friendly NPCs, but most people are afraid of it.
Like a fun-loving dog, it enjoys rolling over onto its back.