Hellfire Wyverns are so named for their foul tempers and fiery visages. Their social structure places all females above all males, due to superior physical characteristics and violent dispositions. Forced subservience of the males causes them to become vicious, petty, antisocial, and passive-aggressive compared to the aggressive and social females. However, orphaned hatchlings raised by foster parents of another species can develop surprisingly even tempers and mellow dispositions, proving that their defining unpleasant nature is, in fact, a learned behavior.

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.

This dragon is afflicted with the belief that he is on fire. All of the other Republicator dragons have attempted to reason with him, to tell him that he only LOOKS like he is on fire, but none of them have succeeded. Fiyah truly believes he is in flames.

The strange thing is, he doesn't take it like a normal dragon. Most of the dragons in the Wisdom Territories know that fire is something to enjoy, from the fire baths in Dooku's spa to the volcanic area where the best gemstones are found. Fiyah, however, acts as though being on fire will kill him.

It isn't out of the ordinary to see him flapping around the main Republicator tower, shrieking "I'M ON FIYAH!" and trying to 'put himself out'. Since Fiyah is a Republicator, the Separators often enjoy sneaking over to the Separator-Republicator border to watch the show, bringing cookies and mocking attitudes.