Vampire Dragons are members of the undead. They sustain themselves by drinking the blood of others. It is said that they are only “alive” at night, and seem dead or asleep during the day, as they cannot endure sunlight for long periods of time. Vampire Dragons can only reproduce by changing the eggs of other dragons, puncturing the shell with their fangs and injecting venom that kills the baby inside.

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.

Salacia von Humpeding is the only Vampire dragon in the Night Watch, and one of the few who does not include her rank in her official name, usually referring to herself as Sally. Many dragons were surprised when she was allowed to join the Watch, due to Commander Sam Vimes—the leader of the clan—having a well-known hatred of vampires. Nevertheless, her night vision and keen sense of smell has made her an extremely useful watchdragon. Like Otto von Chriek, she has sworn never to drink dragon blood, and when not on patrol spends her nights hunting stags and bears instead. Although she and the Nocturne dragon Sergeant Angua initially hated each other, they are now almost friends, and occasionally hunt together.