Deep Sea Dragons, as their name suggests, spend most of their time in the darkest depths of the sea. They have a bioluminescent dorsal spine that serves to attract prey and communicate with their own kind. As with many deep sea animals, they generally eat whatever they can manage to bait. They rarely leave the ocean floor, surfacing only during breeding season. When they do choose to travel to the shallower depths, they avoid bright lights and will only come up far away from shore.

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.

Nerio Tasi is a salty Deep Sea dragon with a love for shrimp. Although the shrimp thing doesn't need an explanation, Nerio Tasi secretly pities the land dragons, feeling as though the ocean is the best place to live on Earth. He is a little proud, but Vespara is quick to humble him. He has the uncanny ability to separate the salt from sea water, so he often makes fresh water for the hatchlings.