Black Marrows are named for their dark colored hides which are encased in a distinct exoskeleton. Their skull and the top edges of their spine push out from under the skin as they age. As such, their young need excessive amounts of calcium for this armor to develop. The older a Black Marrow dragon is, the more skeletal their appearance. They often use their skeletal looks to lure in foolish scavengers or terrify predators. These vicious dragons love nothing more than to crack open bones with their stony beaks and eat the marrow inside. Voracious scavengers, Black Marrows will swarm and devour corpses both old and fresh, sometimes even dragging larger finds to the water to allow them to “ripen.” Despite their dreadful demeanour and often horrid stench, Black Marrows are devoted mates and parents.

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.

Sir Mordred Le Traitre is a bitter male, shunned by most of the Cave's dragons for his species and looks. Whereas most Black Marrows have a good deal of their kind to flock with, the only other of his species that Mordred has for company is Lady Morgan Le Fey. The two spend their days in the caves and skies surrounding the Necropolis where the Vampire Covn and three Zombie Dragons roam.

Mordred is a strong flier, and an excellent fighter when it comes down to it. His talons and spikes can easily frighten off the weaker challengers, and take down the stronger ones with ease. The only flaw on this handsome example of the breed is a chip in his bone-like beak, from a battle with the Gold Dragon, Zaahir Nightingale.