Chinook was a Canadian superhero who reportedly served in both "great wars" (World War I and World War II). He went into retirement during the 1940s. He could manipulate the wind in order to fly. His speed did not exceed that of the birds. He had peak human strenght, allowing him to easily carry another person while in flight. He either did not age at all or aged very slowly during the 20th century. Whether he was a mutant or a mutate was not explained.
When Chinook heard of an emergency near his hometown of Orloo, the decision to respond came natural to him. He wore his costume for the first time in decades and went to help. Seeing Weapon X (Wolverine) rushing to destroy the overloaded Cosmic Collector device, Chinook decided to save the rookie. Then he charged at the device himself. But it exploded before Chinook could get to it and the hero was caught in the resulting explosion. Bathed in cosmic energy, Chinook emerged transformed into a monstrosity.
His new form was a constantly growing mass of muscle. His power over the wind became stronger and his mere presence had significant effects on the weather. His mind became dominated by a single emotion, rage. It took the combined efforts of Puck, Weapon Alpha (Guardian) and Weapon X to displace him to another dimension. "Ten years later" he emerged from the dimensional void to seek vengeance. He faced a version of the Alpha Flight and was killed by its Sasquatch (a humanoid animal, not Walter Langowski).