Stone Dragons have a tough outer covering made of a stone-like material. They eat rocks, using the minerals they contain for nourishment and to keep up their stone outer shell. They rarely move, and are the heaviest of all types of dragons. Although they have wings, indicating flight ability, no one has ever seen a stone dragon flying.

Dragons are highly-intelligent reptilian creatures that—from a human perspective, at least—appear to live forever. Many different varieties of dragon exist, each with their own unique qualities, habitats, and behavior. Adolescence in dragons is usually marked by the growth of a hatchling’s wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. In Galsreim, dragons and humans coexist peacefully.

While the name may imply more of an active, murderous lifestyle, Killer has in fact never harmed another dragon.  He doesn't need to—the ferocious glare he gives to all is enough to paralyze one with fear (sometimes even literally).  He rarely lets any other dragons close enough to him, as he prefers to meander around in solitude.  Comfort and compassion are simply things that cannot register in his mind.