Undine Dragons are named for the water spirits with which they share territory. They have close relationships with these spirits, and are able to communicate with them. In exchange for protection and respect of their mutual freshwater homes, laid eggs are often protected by a blessing. This blessing stays with the dragon into adulthood, and with it they gain potent magical abilities. Sometimes when an Undine Dragon becomes very upset, the ground at their feet may frost over or begin to steam. They have also been observed to manipulate water directly, rerouting raindrops or creating puddles from groundwater. Undine Dragons always live near forest pools, streams, or waterfalls. Both genders take equal part in the raising of young and are very good parents—though they may not remain mated after the offspring are grown.

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.

Tomas Jackson is Alexandri's younger brother. He never lost his youthful imagination and has several invisible friends, like the Green who supposedly pulls plows for the farmer on the edge of town and the Shimmerscale who dances with kings and queens. It is not unusual for him to call another dragon by one of his friends' names. The water spirits enjoy hearing his imaginative stories. His older sister Alexandri could go without them, as he often wanders off while telling his stories. The scribes of the group often write down his words to use as bedtime stories for younger hatchlings. They have coaxed many hatchlings back to sleep with his tales of adventure.

Tomas's favorite tale was about a princess that needed to be rescued. He and his friends bravely vanquished those holding the princess captive and saved her life. In appreciation, she knighted Tomas. He now tells the tale to everyone, as if believing it was true. Naturally, he has made the story more exciting over the years.