Frostbite Dragons first appear at the beginning of winter, creeping in with the frosts. They have found their place in human lore as the spirits of snow, since they only reveal themselves during icy weather. In the depths of winter, they cover the world in blankets of snow and are believed to be responsible for the glittering frost that creeps over everything. Although they appear cold and distant, they are actually rather mischievous and enjoy spending time dancing through blizzards.

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.

While many a dragon from the Cloudtouched Thicket has benefited from Tenderheart's kind, nurturing treatment, Oisin's heart has always been as cold as the bitter north winds. He was never aggressive toward Mentha or her hatchlings, but tried to ignore them outright. Oisin never responded to the prodding of his peers. He only ever seemed to show emotion when hunting, and it was the simple emotion of intense concentration mixed with the slightest bit of... excitement, maybe, or thrill.

His maturation left him largely unchanged. As soon as Oisin could fly, he took off into a snowstorm and hasn't been seen since. Many say that he died that night and haunts the Thicket, ready to gobble up little hatchlings that wander too far from their nest. In truth, he has found peace on a snowcapped mountaintop not far from his birthplace. His pastime of choice involves packing snow around the bare bones of his prey, creating eerily lifelike sculptures that capture their final moments upon the earth.