Origin and Motivations
Not much is known of Kateri Deseronto's early life. She planned to strike down superheroes for their crimes against humanity, crimes including and especially the death of her own son Joey, who was killed in a fight between a unnamed hero and supervillain. She believed that superheroes were all morally wrong, acting only for glory, no matter the damage done to civilian lives.
Coldheart broke into the government agency for which she worked and stole her costume, incapacitating a couple of soldiers before escaping by freezing their hands; during the scuffle she spoke about her armor and twin swords in the past tense, implying she had used the costume and weapons before. She waited in the shadows to finish her "last mission" and overheard a police radio discussing Spider-Man's confrontation with the Hobgoblin, who was attempting to kidnap his own son. As Spider-Man swung into action, Coldheart froze his webline, sending him crashing through a table. This gave Hobgoblin enough time to escape with his son, Jay. Coldheart rushed at Spider-Man, revealing her intentions to strike down superheroes for their crimes against humanity. Spider-Man easily dodged her swords, and kicked her in the face before telling her to stay out of his way. Hobgoblin sent his son flying with a pumpkin bomb to escape Spider-Man, but after Spidey saved the boy from the fall, Coldheart froze him with the edge of her sword as he recuperated. Unable to move a muscle, Spider-Man was defenseless until Jay begged her to leave him alone, since he saved the boy's life. Coldheart was touched, and decided to pursue the Hobgoblin instead of killing the web-slinger.
Cold Hearted Christmas
Spider-Man was on the hunt for Coldheart, who had escaped from prison. He found her running in an alleyway with a bag of money and tackled her. In the fight that followed, Coldheart threw one of her swords at him, hitting the side of his stomach and slowly encasing him in ice. As his body was covered in ice, he secretly attached a spider-tracer to his back before fleeing to a rooftop. Later that night, Spider-Man was freed from the ice, and followed the spider-tracer's signal to Coldheart's apartment, where he saw her giving Christmas gifts to what appeared to be her family. From the apartment above, Spider-Man called the police, who arrested her shortly afterwards. Spider-Man entered her apartment and found that the people in her apartment were inanimate dolls. From her jail cell, Coldheart, thinking about her deceased son, saw a package by the window left by Spider-Man. Inside was a framed photo of her family.
Coldheart was apparently one of the many villains that escaped from the Raft prison. Hiding in Stamford, Connecticut, with some other escaped convicts (Nitro, Speedfreek and the Cobalt Man), she was eventually tracked down by the New Warriors. During the battle, Nitro used his powers to explode the entire neighborhood, causing both the death of hundreds of people, the New Warriors and presumably Coldheart as well. This accident was the trigger for the enactment of the Superhuman Registration Act, and the so-called Superhuman Civil War.
Coldheart apparently survived the Stamford explosion. She was seen in Pleasant Hill, a S.H.I.E.L.D. prison that trapped its inmates by essentially brainwashing them, leading them to forget who they had been and believe they were normal citizens of an idyllic American town. She attacked Nova, stabbing him through the stomach (though Kobik healed him a moment later).
Powers and Abilities
Formerly a flawed sense of logic that superheroes were all villains, and each one was responsible for her son's death. This did not seem to be present after her escape from the Raft, showing far less hostility and even some fear towards costumed heroes.
- Cryonic Swords: She wielded twin swords capable of producing energy that paralyzed with the touch of the blade, or could be projected to freeze objects instantly. Spider-Man stated that he was frozen in place from her paralysis ability, which still points to the energy being cryokinetic.
- Due to her supposed death at the Stamford incident, Coldheart has appeared in various flashbacks referencing the event.
- Coldheart may have died in the Stamford explosion, but was removed from the incident like Night Thrasher or brought back to life during events surrounding Secret Wars.