In her home reality, Heather Hudson was heading up a cutting edge experiment using gamma rays to combat cancer cells when the experiment went horribly wrong. After absorbing a lethal amount of gamma radiation Heather found she could transform into the creature known as Sasquatch. With her new abilities she was invited to join the Canadian super-team Alpha Flight. Her first assignment was to capture a wild monster roaming the Canadian wilderness. That monster turned out to be Wolverine, and Heather was able to capture and subdue him.
Sasquatch and Wolverine stayed with Alpha Flight and eventually married. Alpha Flight became a major force throughout the world but things would eventually deteriorate. Wolverine went insane when a chip in his adrenal gland was activated. Heather tried to reason with him but was forced to kill her husband.
Heather was devastated. Eventually, James Hudson was able to draw her out of her shell. She missed Logan but she and James eventually married. Heather would become Alpha Flight's leader.
In time Heather was ripped from her reality by the mysterious man known as the Timebroker. He told her she had become unhinged from time and would have to help fix the broken chains of reality. If she didn't help, Hudson would be burned to death in a tragic accident in her reality.
As Sasquatch, Heather would help the Exiles complete many missions. Following a fight with vampire versions of the Avengers, the team was separated by a magical spell. Sasquatch and Morph were dropped into a reality at the exact moment that reality's Wolverine escaped from the Weapon X Program. Afraid for Morph's life, Sasquatch knocked him out and hid him. Wolverine quickly tracked Sasquatch, but before the two could fight, Heather reverted to her human form. Wolverine stopped dead in his tracks. Before they could harm each other, Heather was teleported away and reunited with the Exiles.
During a mission when the Exiles were forced to face off against their reality-hopping counterparts, Weapon X, Sasquatch was mortally wounded by her teammate, Magik. Heather saved Nocturne's life, pushing her out of the way of Magik's sword slash. Bleeding to death, Nocturne possessed Heather and transformed her into Sasquatch, allowing her healing powers to kick in.
Recently, a visit to a mystically empowered reality revealed that the true source of Sasquatch's power was not gamma radiation but actually Tanaraq, a Great Beast of the North. The Great Beast took over her body. She would have remained under Tanaraq's influence if not for the magic of Alpha Flight's Shaman. Unfortunately, Heather lost the ability to transform into Sasquatch. Recently, Heather has been acting as a mission control for the team, remaining at the crystal palace and giving the team information on their missions.