New X-Men
Xorn debuts in New X-Men Annual 2001 imprisoned by the Chinese government, where a corrupt mutant official offers to sell him to John Sublime. Xorn is forced to wear a skull-like mask designed to restrain his energy output. The X-Men and Sublime's U-Men find Xorn just as he is attempting to commit suicide by removing his mask, which would destroy the Earth. Cyclops (with the help of Emma Frost) is able to establish contact with Xorn, convincing him not to kill himself, and offers him a position among the X-Men. Xorn is next seen in New X-Men #122, where Cyclops tracks him down to a monastery, where he is told by the monks that Xorn has demonstrated healing powers. The pair are captured by the Shi'ar but arrive at the X-Mansion in time for Xorn to heal the X-Men of a nano-Sentinel infection, restoring Professor Xavier's ability to walk in the process.
Despite the ordeals through which he had passed, Xorn is optimistic, open, and even somewhat naive. Xorn keeps a diary to share his thoughts with Professor Xavier, since Xavier is "blinded by the sun beneath mask" and cannot read his mind. Here he details his interactions with Chinese immigrants and the residents of Mutant Town in New York City, in particular an incident where he failed to save a young mutant from being killed by frightened policemen. Xorn is soon put in charge of the "Special Class", a group of physical and social misfits attending the Xavier Institute. Though he hopes to befriend these students, he becomes disillusioned as they mock and insult him. He remains determined to help his "Special Class," even saving their lives from a group of U-Men.
In the storyline "Planet X", Xorn removes his mask, revealing himself to be the X-Men's archnemesis Magneto, who has been believed dead since the destruction of Genosha. Magneto explains that the Xorn identity was an elaborate ruse crafted with the help of Chinese supporters, in order to infiltrate the X-Men; even the prison was a fake. Having returned Xavier to a crippled state (Xavier had not been healed - Magneto merely used the nano-Sentinels to "glue" his spine together), Magneto levels the X-Mansion and conquers New York City, where he enslaves the human population and destroys much of the city. He attempts to recreate the Brotherhood with Toad, the rebellious Stepford Cuckoo Esme, and the members of Xorn's "Special Class."
Magneto finds, however, that many of his recruits are unresponsive to his ideas and approach, with some asking for the return of the more humane Xorn, and others doubtful that Magneto has truly returned, much to his chagrin. Indecisive and relying heavily on the drug Kick to augment his power, he struggles to maintain the loyalty and respect of his followers. He announces a plan to invert the planet by reversing its magnetic poles, and employs increasingly fascistic methods (including the construction of a Nazi-esque crematorium in which he plans to eradicate the remaining human population of the city). He also appears to be experiencing a form of Dissociative identity disorder, as the "Xorn" persona begins to manifest itself as a voice within Magneto's head, claiming to be the embodiment of Magneto's wisdom, idealism, and nobility. After his defeat at the hands of the X-Men, but before his capture, he fatally wounds Jean Grey; Wolverine, in a berserk fury over Grey's death, decapitates him.
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