The Leper Queen was five months pregnant with her daughter when a mutant passed by and her daughter started to move. When she was a few months old, she could already create sparks. At the age of two years, she set fire to their house which resulted in her dying and her mother's face being burned. It was then that the Leper Queen decided to kill all mutants.
Decimation
The day afterM-Day, the Leper Queen attacked the Xavier Institute with the Sapien League. She was first seen attacking Mammomax, Erg, and Peepers who were racing to Xavier's mansion for sanctuary. The Sapien League tied them to X-shaped crosses and attempted to burn them to death. They were stopped by Wolverine and Colossus who had seen the smoke from their attacks. After this failure, she led an attack on the mansion itself. It was only by the combined efforts of the X-Men and the Sentinel Squad O*N*E that the Sapien League were stopped. During the fight, Iceman was captured. When the Leper Queen tried to execute him, his sudden regaining of his powers caused her arm to freeze, and she fled, encountering both Outlaw and Peepers as she escapes. After tracking Polaris and Havok to Puerto Rico, members of the Sapien League were attacked by Havok, who stopped their assault on an old man. They then called the Leper Queen, who was visiting the grave of her daughter. She arrived to kill Havok and Polaris, but was stopped by Havok who had just killed Daap, an alien who had crash landed and bore a striking resemblance to former X-Statix member Doop. The remains of the alien reformed and carried Polaris and the Queen to a nearby temple of Apocalypse. Apocalypse found the Leper Queen's bloodlust and thirst for vengeance too much even for him, and denied her the chance to become one of his Horsemen, Pestilence, and gave that "honor" to Polaris instead, chaining up the Leper Queen in a dungeon as a result.
It is unknown how she eventually escaped, but it was later revealed that the Leper Queen, alongside other prominent anti-mutant leaders, had been forcibly recruited into the ranks of the Purifiers. She was saved before being executed in the electric chair for the murder of two girls in Guatemala and infected with the Transmode Virus by Bastion, along having her head and face even more disfigured. At an anti-mutant rally held in Iowa by the Friends of Humanity, the Leper Queen delivered the former Morlock known as Beautiful Dreamer into the crowd, where due to her being injected with a modified version of the Legacy Virus was responsible for killing all of the people attending the rally along with herself, though the Leper Queen felt guilt over killing the humans for Bastion's cause. After a similar incident where the mutant Fever Pitch was infected and used to kill thousands of innocents, she later captured Surge, Hellion and Boom Boom, injecting the same virus into Surge and Hellion. She then sent both of them to the United Nations for the same fate as Beautiful Dreamer. She kept Boom Boom alive only as a precaution, knowing that some X-team would come to stop her. While in the middle of giving X-Force an ultimatum: to choose between saving the teens or Boom Boom, Cyclops called the team away by forcing them to travel through time. Wolverine objected, demanding that Domino take the shot to kill Leper Queen, but it was too late and the team was teleported into the future. Boom Boom, left in the hands of the Leper Queen, was then told by Leper Queen that she had used Boom Boom to lure X-Force to her location. Since Bastion would not allow the Leper Queen to kill herself, she had planned for X-Force to kill her to save Boom Boom. Leper Queen then shot Boom Boom between the eyes at point blank, killing her, before stating that X-Force "failed us both." In a paradox, X-23 came back to a point three seconds after the jump, shooting the Leper Queen and saving Boom Boom. The Leper Queen thanks X-23 for killing her, and thus freeing her from Bastion.
Powers and abilities
The Leper Queen has a competent ability with weapons. She is also a skilled fighter and has been infected with the Transmode Virus by Bastion.
Personality
During the Sapien League's attack on the mansion, it is said that she completely hates mutants and has been on many mutant hunts. Her mission in life is to kill all mutants in reparation for her daughter's death. She hides her burnt face with a mask that lifts just when she's about to suppress her opponents.
