Real name: Unrevealed
Other aliases: Professor Charles Xavier, Professor X
Former aliases: None known
Identity: Secret
Occupation at time of death: Substitute teacher/leader of the X-Men
Former occupation: Subversive, second-in-command of Factor Three
Legal status: Citizen of the United States of America with no known criminal record
Place of birth: Unrevealed
Place of death: New York City
Cause of death: Mortally wounded by the explosion of an oscillotron machine
Marital status: Presumed single
Known relatives: None
Base of operations: Professor Xavier's School for Gifted Youngsters, Salem Center, Westchester County, New York State, (former) Factor Three headquarters, at an undisclosed location in Europe
Group affiliation: X-Men, (honorary member), (former) Factor Three, X-Humed
First appearance: X-MEN (first series) #35

History: Changeling was a mutant shape-changer who was second-in-command of the subversive organization Factor Three. He later reformed and, on Professor Charles Xavier's request, impersonated him while the real Xavier went into seclusion to prepare to repel the forthcoming attempt by the alien Z'nox to conquer Earth. He later died in defeating Grotesk, the lone survivor of a subterranean race, who sought to destroy the Earth.

The voodoo practitioner called the Black Talon later resurrected the Changeling as a zombie and forced him to serve in a team of other mutant zombies called the X-Humed. However, after the Black Talon was defeated by the She-Hulk, the Changeling once again became truly dead.

Height: 5 ft. 11 in.
Weight: 180 lbs.
Eyes: Brown
Hair: Black
Strength: Normal

Special skills and abilities: Extraordinary actor, highly trained and efficient organizer of subversive activities

Known superhuman powers: Changeling was a metamorph who could alter his physical appearance and voice to mimic that of any other human being. His power could also transform the appearance of his costume as well. Changeling was also endowed by Professor X with limited telepathic abilities.