Dark green dragons, once they mature, appear to become an entirely different species. However, this isn’t true. Rather, they burrow underground and get nutrients from their vines. These vines are sometimes referred to as Dragon Grass. These dragons are very violent, and will use their vines to capture, kill, and eat anything that moves, as well as nearby plants. Luckily, their range is limited and they cannot use magic. Dark green dragons tend to be easy to spot since they usually kill all plants around them and thus are usually surrounded by a large clearing.

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.

Jirachika is a convicted hatchling killer, and he is known for committing at least twenty-three counts of child murder. Dragons who claim to be "bystanders" of these events say that Jirachika drags the hatchlings towards him and slits their throats with the sharp thorns on his vines. Despite his horrendous acts, the Uncita clan has not sentenced him to death mainly because he is not truly a member of the clan. It was discovered that Jirachika was born on the outside of the clan's territory borders but not actually inside of them. The clan's human owner is unsure of who his true parents are, but she made a guess for the sake of recording information on her scroll. It is also commonly believed that Jirachika lured hatchlings to him with a simple and soft little lullaby, and the first lyrics supposedly go, "Come little children, come with me. Safe and happy you will be..."