Soo was the headmistress of St. Damia's School for Young Women in Canada, which was the front of a coven of witches. Following her death when she choked on a hokey puck, Headmistress Soo's students attempted to use a ritual to bring her back using the body of the demon Shiklah was a vessel. To this end, they captured Shiklah's husband Deadpool, and used a spell to bring his heartmate to him. Spider-Man was unexpectedly summoned instead of Shikhlah, as he turned out to be Deadpool's heartmate instead of her. The girls settled for him and scattered Soo's ashes on the confused hero, causing Soo's soul to slowly take over Spider-Man's body.
The girls' plan concurred with the Leviathon invasion, so both Spider-Man and Deadpool's attention was diverted to the landing of a giant monster in Toronto. When Deadpool was temporarily swallowed by the monster and Spider-Man found himself starting to lose control of his body, he got Soo's pupils to help him defeat and subdue the monster.
Having taken control of Spider-Man's body, Soo encouraged her pupils to help her drown the beast in a lake nearby so once its soul escaped its body, they could feed on it. Soon after sinking the creature, Soo affected her students with an age regression hex so she could have the monster's soul entirely for her alone. However, the creature emerged from the water and shoved them into the top of the CN Tower. Deadpool convinced Headmistress Soo to help him even though the monster's attack had weakened her, so she barely had strength for one final spell.
Soo and Deadpool jumped at the monster, and Soo used an intangibility spell which allowed Deadpool to phase through the monster's head to its skull and set off a handful of grenades which killed the creature. The spell faded out Soo's final strength, causing her to leave Spider-Man's body.
Powers and Abilities
Magic: As stated by her pupils, Headmistress Soo was a powerful witch.
- When Headmistress Soo was in control of Spider-Man's body, the eyes in his mask became narrower, and their black contour sharper.