Black Dragons are warriors. They are strong and capable in battles of force, but also ample magic users, capable of devastating opponents with their spells. Their bright eyes give them excellent night vision, which is why they generally hunt during the night.

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.

Guanin and her best friend Cytosin are basically inseparable. Wherever one of the two can be found the other is not far off. The only other friendship that is as close as theirs is that of Adenin and Thymin another pair of dragons that simply can't stay alone for any considerable time. The four Black dragons are often seen together and work as a messenger group between Fumee and Fury, making sure all the information gets where it belongs and nothing is lost.