Thunder Dragons are the masters of electricity. Their wings gather energy as they soar through the clouds, and when they clap their wings together they can create devastating arcs of lightning. They can stay airborne nearly indefinitely, landing only to sleep and breed; they catch their prey from the air and take moisture from the clouds. A thunder dragon’s roar is considered to be an omen of misfortune.

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.

Tonitrua is known for his incredible ability to harmonize with thunder and lightning, earning him the name of "Stormsinger" which was later added to his actual name, thus, creating Tonitrua Stormsinger. He was a kind and noble dragon, always helping, always caring, unless attacked. Then he would transform into a raging monster. All feared him, and yet all loved him. Then one day, the mother of a son that he had saved from starving gave him the Eye of Onyx, one of the most powerful jewels on the planet. It corrupted him. He had been trained under the strict rule of the highest fighting dragon, making him one of the most dangerous dragons in the land. All that bored him, all that cursed him, were utterly destroyed by the power of the Eye of Onyx. Then one unremarkable day, he dropped the eye on the ground, smashing it to pieces. Suddenly, like having a veil lifted off his eyes, he could see the destruction that he had created. He had no place, so he went away.