Horse Dragons have equine-shaped bodies and hooves instead of claws, which allow them to be fast runners. They specialize in running takeoffs, which are quicker than taking off from a stand-still. Horse dragons are able to stalk their prey from the ground then quickly execute an aerial attack for the kill.

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.

A curse befell a human named Imiut upon birth, due to a corrupt pact by his father, who desired power over anything else. The boy was subsequently shunned by his father, who feared his pact with another plane. The boy set out, struggling with his curse, and traveling to find a cure for it. Years ago, first getting a grasp of his powers, he summoned a nightmare (or, more correctly, a nightstallion) from the plane that he was linked to. Given the name Ketorio, upon his first summon, he was just a foal. He made a pact with Imiut, the two joining forces.

When not in this plane, Ketorio watches over Imiut from his shadow. He is fiercely protective of the man, and hopes both that Imiut will find a cure for his condition, and that he will still be able to keep his ties with him once the bond between Imiut and the shadow plane is severed. He provides both transport and protection, not minding either in the least. Imiut is kind towards Ketorio, and the two have developed a close friendship.