# Proteus (Marvel Comics)

Kevin MacTaggert, best known as Proteus and also called Mutant X, is a character appearing in American comic books published by Marvel Comics and is commonly associated with the X-Men as an antagonist.
Kevin was the mutant son of Scottish genetic researcher Moira MacTaggert and politician Joseph MacTaggert. Kevin had reality-warping and possession powers and lived most of his life in forced seclusion at his mother's Muir Island research facility.
Kevin's attempt to escape Muir Island and find his father made up a 1979–80 Uncanny X-Men storyline that was adapted in X-Men: The Animated Series. In 2009, Proteus was ranked as IGN's 77th-greatest villain of all time.

## Publication history

Created by writer Chris Claremont and artist/co-writer John Byrne, Proteus first appeared in The Uncanny X-Men #125 (September 1979), though hints to his character appeared in earlier issues. He was referenced off-panel in The Uncanny X-Men #104, and appeared already possessing a host in The Uncanny X-Men #119.

## Fictional character biography

Kevin MacTaggart was the son of Moira and Joseph MacTaggert and was conceived after Joseph severely beat and raped his wife. Moira left Joseph without telling him she was pregnant and raised Kevin at her mutant research centre on Muir Island, off the coast of Scotland. Kevin eventually began manifesting his mutant abilities, becoming a danger to everyone around him. To protect herself and others, Moira was forced to confine Kevin in a specialized cell and referred to him only as Mutant X.
Kevin remained confined for several years until his cell was damaged in a fight between Magneto and the X-Men, at which point Kevin escaped by possessing the body of Angus MacWhirter. Unfortunately, his stolen body was less effective than his original skin at housing his energy form. Reasoning that a more powerful host might sustain him for longer, Kevin decided to possess another resident of Muir Island, the powerful mutant known as Phoenix, but was unable to overcome her psychic powers. Without the esoteric energy fields of his cell to sustain him, Kevin began to burn his body out, and so began to possess human host bodies, one after another. He went after Polaris next, but ultimately ended up taking the body of one of Jamie Madrox's duplicates.
The X-Men arrived to confront Kevin, so he fled to the Scottish mainland, but was caught by Wolverine and Nightcrawler. In the ensuing fight, Kevin rejected the Mutant X label and named himself Proteus after the Greek god of myth and the cell in which he had been confined. Proteus tried to possess Wolverine's body, but was forced out by the Adamantium in Logan's skeleton. He attempted to possess Storm, but Moira managed to drive him off by firing at him with a long-range sniper rifle, out of the range of his powers.
Proteus fled to Edinburgh, where he possessed his father, Joseph, and made a last stand against the X-Men. His host body was destroyed in the battle, but before Proteus could take another host, he was punched by Colossus, disrupting his energy form and apparently killing him.
Several years later, A.I.M. attempted to recreate Proteus using a woman named Harness and her mutant son, Piecemeal, to absorb Proteus' dispersed energy form. As the boy went about absorbing the energy, his body grew too large for his system to handle. Eventually, what was left of Proteus's consciousness and Piecemeal merged as one being.
The combined efforts of the New Warriors, the New Mutants, the Muir Islanders, and the original X-Factor team were not enough to defeat the resulting creature, but when the amalgamated being decided that it would not find happiness, it decided to disperse itself, effectively committing suicide.
Some time later, Mister Sinister and the Gamesmaster also attempted to recreate Proteus by stealing a disc containing his DNA matrix, but were prevented by Nightcrawler, Shadowcat, and Rachel Summers.

### House of M and Exiles

When the Scarlet Witch altered history and created the House of M reality, she inadvertently released Mutant X on the world again. Just as before, Moira MacTaggert discovered her son Kevin possessed vast mutant powers that were eating away at his body and tried to cure him of this affliction, but in this new reality, any attempt to "cure" mutation was a capital offense, and Magneto's Sentinels destroyed Moira's lab on Muir Island, setting Kevin loose. Mutant X soon became an infamous Scottish serial killer known for the desiccated corpses he left in his wake.
Kevin encountered the Exiles and managed to escape the House of M reality by stealing data from the Panoptichron and possessing the bodies of various Exile members, though other reality manipulators such as Longshot seemed immune to his powers. Proteus finally possessed the body of Morph, which did not seem to deteriorate due to his possession.
Perhaps due to lingering memories from his time possessing Mimic, Proteus became obsessed with Blink, who tricked him into wearing a portable Behavior Modification System and brainwashed him into believing himself to actually be Morph. Unaware of his true identity, he joined the Exiles, much to the discomfort of the other Exiles. He required regular manipulation by the Behavior Modification System to maintain the brainwashing, but the device was destroyed by chance during a fight between Psylocke and Sabretooth.
Morph's consciousness eventually reawakened and confronted Proteus, offering him chance to work together and share his body and powers in order to do good. Proteus accepted, and the two began to work in harmony, better than either could alone. Some time later, Proteus and Morph were forcibly separated when the Exiles were absorbed into the Panoptichron; Proteus was absorbed into the walls, but Morph was left behind.

### Necrosha

Proteus was eventually restored as dispersed energy on Earth-616 and began to try to recreate his physical form via the same process used by Harness and Piecemeal. When Selene began using the Technarch transmode virus to resurrect dead mutants, Proteus took advantage of her work by affixing a small portion of his energy signature, and therefore his consciousness, to Destiny as she was resurrected. Although the amount of Proteus energy involved was not enough to truly possess Destiny as he had done in the past, Proteus was able to influence Destiny's perceptions and cause her to foresee a great threat on Muir Island.
When Destiny tried telepathically contacting her foster-daughter Rogue, she instead found Blindfold and passed on her vision (and unwittingly a portion of Proteus' energy). Proteus manipulated Blindfold into confirming Destiny's vision and Cyclops dispatched Blindfold to investigate. Once they arrived, Proteus was able to use Blindfold like a "psychic magnet", soaking up Proteus' energy until enough energy was consolidated in one place to resurrect Kevin MacTaggert and allow him to fully possess Blindfold.
Proteus turned on the X-Men, particularly his murderer, Colossus. He demonstrated the ability to possess several X-Men simultaneously, but was ultimately defeated when Magneto disrupted his energy signature, killing him once more.

### Agent X

Some of Proteus's energy was found drifting in the astral plane by the Shadow King, who used it to as a source of power in the battle between him and Xavier. In the battle's final moments, Shadow King spread Proteus as a psychic infection in London. Xavier, now inhabiting Fantomex's body and calling himself X, defeated the Shadow King, but accidentally reconstituted Proteus in the process. Proteus allowed X and Psylocke to enter his mind, where they were welcomed by a young Kevin McTaggert. Kevin expressed a wish to atonement and change, as he believed he was only ten years old at the time Colossus killed him. Following that, he had only a few brief times to see the world before he was dispersed, but he had spent ten thousand years on the astral plane reflecting on the harm he had caused others and now wished only to be left alone. X did not trust him and attacked instead.
In retaliation, Proteus temporarily merged the physical bodies of X and Psylocke and sent them back to London. He then attempted to bring the astral plane into the real world and traveled to the Scottish village of Fetters Hill, granting its citizens the ability to make whatever they wished real. As the X-Men confronted Proteus again, the village had already fallen into chaos, becoming a gestalt of the villagers' mindscapes, but the X-Men were eventually able to disperse Proteus and reverse the damage he had caused to reality.

### House of X

Proteus was shown to be an inhabitant of Krakoa, apparently inhabiting a Professor X husk. He joined forces with Elixir, Hope Summers, Egg, and Tempus as The Five and together they used their talents to resurrect dead mutants.

## Powers and abilities

Proteus is an Omega-level mutant who possesses a vast psionic ability to manipulate and alter reality. He exists in a state of pure psionic energy and can take possession of human bodies; however, the bodies of most beings burn out within hours or a few days. Proteus can leave a body before it is destroyed, but he usually does not. No possessed person has been shown able to resist or break free of Proteus's domination. Proteus has access to all the memories of his host while he possesses them and after he has left the body. Proteus has occasionally exhibited some telepathy, perfect recall, and the ability to mentally download computer information.
Proteus' energy form is disrupted by metal, making living beings with metal in their bodies immune to the possession. If his form is disrupted enough, it can be dispersed, essentially killing him until it is reconstituted.
His reality manipulation powers allow him to transmute matter and bend the laws of physics according to his imagination within a certain range. Using this power he can transform objects into other objects or living creatures, transform energy into matter, manipulate weather, affect people's bodies, or strip a person of their powers. Proteus's reality warping ability is temporary and contingent upon line of sight: once out of his sight, any of his changes will be undone.
Because Proteus is a being made of energy, he is virtually immortal, as his consciousness can reform after being disrupted. Proteus has at times exhibited the ability to transport himself inter-dimensionally, though it is unknown if this is an innate power or if he needed to use a connection to the Panoptichron to accomplish this. After his revival through Destiny during the events of Necrosha, Proteus is shown to be able to possess multiple individuals simultaneously.

## Other versions
### Star Trek/X-Men crossover

In the Star Trek/X-Men crossover, the spirit of Proteus crosses over to the universe of Star Trek because of a rift created by Star Trek antagonist Gary Mitchell (who also had reality warping powers). Proteus is able to reanimate and inhabit Mitchell's corpse, which does not deteriorate like other hosts. While chasing Deathbird, the X-Men team up with the crew of the USS Enterprise to stop Proteus, who allies with Deathbird to escape the planet.

### Ultimate Marvel

In the Ultimate Marvel universe, Proteus was named David Xavier and was the son of Moira MacTaggert and her ex-husband Professor X (Charles Xavier). He escaped his mother's keep on Muir Island, seeking his father in order to kill him. Proteus killed thousands of people across the world in an attempt to discredit the X-Men, including Psylocke's partner Dai Thomas, an agent of S.T.R.I.K.E. After Xavier refused to kill David, Colossus killed them both by crushing them inside a car.

## In other media

Proteus appears in a self-titled two-part episode of X-Men: The Animated Series, voiced by Stuart Stone. This version is able to assume human form at will, and his possession abilities are not lethal. He comes into conflict with the X-Men while searching for his father, but Professor X manages to calm him using his psychic powers, allowing him to reconcile with his parents.