Odd is a twelve-year-old Norwegian boy with a Scottish mother. Following the death of his father from pneumonia, Odd suffers a permanently disabled leg in a logging accident and relies on a wooden crutch for mobility. He possesses a highly practical perspective on life and maintains a cheerful demeanor that deeply frustrates his isolated community. Mistreated by his stepfather, he prefers the solitude of the snowy wilderness.

Loki is the Norse trickster god, currently trapped in the form of a fox after being outsmarted by an enemy. He retains his striking green eyes and slippery personality even in his animal body. He speaks highly of himself and operates with a selfish approach to life, yet his sudden lack of magical power forces him to rely on a human boy during the harsh winter.

Thor is the Norse god of thunder, presently cursed to live as a massive brown bear. He maintains his immense physical strength, stubbornness, and aggressive nature despite his animal form. He readily accepts Odd's help when trapped and offers the boy a ride on his back, forming a protective but cynical alliance with the human.

Odin is the king of the Norse gods, transformed by a curse into a giant eagle. He is proud, distant, and speaks very little in his animal state, preferring to watch events unfold from above. Even while cursed and losing his human nature faster than the others, he commands the absolute respect of the other gods and oversees their chaotic interactions with quiet authority.

The Frost Giant is an immense, icy being from Jotunheim who guards the walls of Asgard. He operates with a mix of physical power and surprising simplicity, having successfully taken control of the gods' home. He desires to bring something beautiful back to his bleak homeland and seeks to avenge his fallen brother.

Freya is a highly powerful Norse goddess who resides in Asgard. She possesses a whimsical view of the world and operates with an uncanny, intimidating power beneath her kind exterior. She serves as the ultimate prize desired by the giants of Jotunheim, though she demonstrates absolute control over her own domain.

Odd's mother is a Scottish woman who was kidnapped during a Viking raid but eventually built a loving marriage with her captor. She is deeply protective of her son, frequently sharing stories and songs from her homeland with him. Following her husband's death, she struggles with melancholy and marries a cruel man simply to secure a future for her child.

Fat Elfred is a villager with seven children from a previous marriage who takes Odd's mother as his second wife. He misuses alcohol and treats his stepson with open, physical hostility. His constant cruelty drives Odd to spend most of his time isolated in the snowy wilderness.

Odd's father was a Viking and woodcarver who died from pneumonia after saving a pony from freezing waters. Though he began his marriage by kidnapping his wife, they eventually formed a deeply loving relationship. He leaves behind an uncarved block of wood that becomes highly significant to his son.

The Giant's Brother is a deceased figure from Norse mythology who originally built the great wall around Asgard. He made a deal with the gods to receive the Sun, Moon, and Freya as payment, but was tricked and ultimately killed before he could finish. His death serves as the primary motivation for his brother's invasion.

Heimdall is a Norse god charged with protecting the Rainbow Bridge that connects Asgard to the human world. He is forced by the Frost Giant to transport the newly cursed animal-gods out of their home city, trapping them in Midgard.

Olaf the Tall is a Viking raider who dies at the hands of a Scotsman during an expedition. His death forces Odd's father to take charge of the expedition's ponies, indirectly leading to the events that cause the woodcutter's death.