Golden Wyverns are known for their beautiful metallic scales and rumored magical abilities. Living high in the mountains, these dragons do not believe in killing for sport or pleasure. They will hunt only when hungry and defend themselves when provoked, but will avoid killing to the best of their abilities. Golden Wyverns often mingle with other dragons of similar color and take pride in their shimmering hide.

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.

One night, as the full moon gleamed brightly above the Mountains of Elgar, casting its eerie light over the land, the Hellfire named Nyx of the High Family flew over the slumbering mountains. By chance, a gleam of gold caught her attention, bringing her to the egg of Thanatos. After being declared worthy by Chaos, leader of the High Family, Thanatos was raised to serve as one of the Posluga. From a young age, he has always been affiliated with death and is closely tied to Hypnos, his "brother", close companion, and personification of sleep. The two are almost always seen together, and while Hypnos is viewed as a sly troublemaker, Thanatos is feared for his cold and serious personality. He cares little for the feelings of others and sees only the practical, and often enough deadly, outcome of events. He does not so much take joy out of the death of other living things then he feels a sense of duty towards his role. He is the living representation of Death in the Posluga.