Split Dragons use their sharp teeth and wings to hunt large animals and rarely eat plants. They are intelligent dragons who enjoy mental challenges, preferably alone; Split Dragons are normally solitary except during mating season. When mating, many dragons come together in a group to raise their eggs and hatchlings. These groups tend to be very noisy—reminiscent of a thunderstorm—and last only until the hatchlings are capable of surviving on their own.

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.

Two-headed dragons are unique enough to deserve a separate classification from ordinary dragons. They have two necks, two brains, two mouths, but one stomach and one main body. The two heads usually work together, but there are times when they will fight each other, snapping back and forth. Their unique anatomy prevents them from breeding with single-headed dragons.

Castello (Cas for the right head, Tello for the left) is the second two-headed dragon on the Amadeus line and only mate of Finnarynne Amadeus.

He was bought by a mage in a far away village from a mysterious dragon merchant man who got his egg ages before from a cave. The egg wasn't believed to hatch, according to the man, but it was bought anyway.

It was a bit surprisingly when it did and came out to be a two-headed male, the perfect mate for the mage's companion, Finnarynne. Although, it took so much time until the female dragon could trust the young male and produce an egg.

Castello never gets too attached to their offspring, because of the personality of the Cas-head. He prefers to let the eggs and hatchlings go to other people, because in his dragon mind, he knows that he may meet them again, someday, when flying around the mountains, as his fellow mage owner takes care of the other dragons and eggs on her lair on the base of said mountains.