Real Name: Professor Charles Francis Xavier
Affiliation: X-Men (Headmaster)
Origin: New York, NY
Powers: Telepathy
Known Relatives: Cain Marko (Juggernaut, step-brother)
Background: Charles Xavier was born to a wealthy family and should have lived a very comfortable life. However, early in life, Charles's father mysteriously died, and his mother eventually married her late husband's former partner, Dr. Kurt Marko, and Charles received a step-brother, Cain Marko. The family moved to a small town outside New York called Bayville, in order for Charles and his mother to attempt to avoid some of the painful memories of loss. Life went on for Charles, despite bullying from Cain. In his early teens, Charles suddenly began hearing other people's thoughts, and after studying genetics he realized he was a "mutant," someone born with an X-Factor in their genes that allows them to have superhuman powers.

At some point, Charles was crippled and lost the use of his legs. How exactly this happened is unknown. He also defeated his step-brother, who had become the near-invincible Juggernaut, and designed a prison tank for him that is maintained by the Federal government. Soon, while lecturing at a university, Charles met another young mutant by the name of Erik Lensherr. The two were instant friends, believing they could eventually make the world safe for mutants. The two differed in their methods of doing this, similar to the difference between Dr. Martin Luther King, Jr. and Malcolm X. By Together, they developed a mutant-finding computer named Cerebro. However, after Charles met Ororo Munroe (Storm) and recruited her to find the wild man named Logan, Erik donned his persona of Magneto and challenged Charles for Logan's loyalty. When Logan chose Xavier's way, Magneto left.

With the small fortune he had inherited from his mother, Charles turned his family's mansion into his School for Gifted Youngsters, in the hope of helping young mutants learn to control their powers. Ororo and Logan became instructors at his school, and took the codenames Storm and Wolverine. Using his powerful mutant-tracking computer, Cerebro, Charles sought out his first two students, Scott Summers, who possessed optic blasts, and Jean Grey, with mental powers similar to the Professor's. Eventually "Professor X" recruited others, and the fledgling X-Men were born.

Professor X trained the X-Men to control their abilities, and to use them against those who would harm others, such as the Brotherhood. He guides his students sternly, but with a fatherly love that binds the entire team together. Recently, Professor X brought a number of new students to the school, and recruited a new teacher, the Beast, a Bayville alum who had previously turned down an offer to join Xavier's cause. All together, Professor X and his staff run the Institute as a supplementary program for the students, who all attend Bayville High for their regular classes.

At the beginning of the infamous "Day of Reckoning" fiasco, Professor Xavier appeard much more stern and unforgiving of his students, upset that they were unprepared to fight against Magneto. Because of this lack of training, Xavier announced to his students that they would be joined by the Brotherhood. This action upset Cyclops, who subsequently left the team. Xavier assembled the team, leaving the New Mutants at the Institute because they were inexperienced, and flew off to find Wolverine and attack Magneto, still believing that Magneto was responsible for Wolverine's disappearance. As soon as the Velocity and X-Jet were gone, the Mansion went into Defcon 4, locking Magma outside and the rest of the New Mutants inside. Moments later, Cerebro set itself for emergency demolition. When Cyclops returned, after prompting by Boom-Boom and Magma, he was able to save himself and the New Mutants at the last minute. In New York, the battle raged between the X-Men/Brotherhood team-up and Magneto's own mutants, Sabretooth, Pyro, Colossus, Gambit, and Quicksilver who had led the teams into a trap, knowing he would be same. As the battle continued, and Magneto's team was defeated, the Sentinel, created by an anti-mutant fanaticist known only as Trask, surfaced. The battle between the X-Men/Brotherhood and the Sentinel was so massive that it devastated a decent sized area of New York, and was played around the world on tv, revealing that mutants exist. After the battle was finished, the team had to flee quickly, leaving Beast, Rogue, Spyke and Blob behind. This was very uncharacteristic of Xavier. However, when the remaining team returned to the destroyed Mansion, Cyclops accused Xavier of destroying the Mansion and nearly killing him and the New Mutants, then lifted him out of the chair and tossed him to the ground. The others tried to subdue Cyclops, when Xavier stood up and morphed into Mystique.

Eventually, thanks to information from the mutant-sensing Caliban, Cyclops led the X-Men to Professor X, and the X-Men freed their mentor from Juggernaut's stasis chamber, where Mystique had stashed him. With news footage identifying the X-Men as Bayville students and the Institute being rebuilt, Professor X had the X-Men return to Bayville High, following a successful referendum on their status. When Mesmero resurfaced to find the second key to Apocalypse's tomb, Xavier was the one who discovered that the destruction of the second key was exactly what Mesmero wanted, as the spider was a guardian to protect against Apocalypse's return.

Later, Apocalypse captured the Professor and turned him into one of his Horsemen. Outfitted with bio-tech weaponry and a flying horse, Xavier was able to ignore his crippled legs and fight aerial battles. The X-Men were forced to fight their mentor, with Jean providing most of the telepathic support. Eventually they defeated Apocalypse and the Professor was returned to normal. Following the event he appeared to have a precognitive flash of various changes that would soon occur to his students, some good and some bad...

Professor X as Horseman