When Water Dragons mature, they lose the ability to survive on land, entering the water permanently. They are adept swimmers and eat whatever fish are in the lake they live in. They tend to inhabit the same lake for their entire lives, although a few live in the ocean and swim all over the world.

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.

Levi-thun is the oldest water-bound dragon in Jmm's caverns, and so is in charge of the underwater sections of the caverns. Often the only one capable and trusted enough to hold responsibility for the water-based younger dragons, Levi-thun has little choice but to serve as their mentor for the majority of his time, though he still enjoys forming new sections of cavern and filling these with water. While he does prefer the freshwater half of the underwater section, where his personal space is located, his duties usually require that he visit the saltwater section reasonably often.