En Sabah Nur, also known as Apocalypse, is a powerful mutant who is the master of Mister Sinister. In the alternate future, Apocalypse took over the planet and Mister Sinister and Cyclops appeared to be his close allies.
- Bald of Evil: He does not have any hair and is very evil.
- Big Bad: He would have served the role as this in the second season had the series not been cancelled.
- The Chessmaster: He was frequently working behind the scenes.
- Eviler Than Thou: He is this to Mister Sinister.
- Man Behind the Man: To Mister Sinister, though if you're familiar with many other versions you probably guessed that.
- Mutant: He is a very powerful one. However, his powers are never shown in this series.
- Powered Armor: He is shown to be wearing this.
Boom Boom/Tabitha Smith
Tabitha Smith, also known as Boom Boom, is a mutant who was a prisoner of the MRD before being rescued by the X-Men. She has the ability to create balls of plasma.
Peter Rasputin, also known as Colossus, is a mutant and member of the X-Men. Once Jean Grey blew up the Xavier Mansion, Colossus left the X-Men. He returned to Russia to be with his family. When Wolverine reformed the team, Colossus turned down the offer because he did not want to leave his family again. Colossus has the ability to transform his body into steel-like substance, granting him superhuman strength and durability
- Advertised Extra: Colossus was featured in some early promotional material - he even got an action figure! - but was Put on a Bus in the pilot, never to be seen again.
- The Big Guy: He's physically huge (7'5" in his armored form), and his abilities to both ignore and dish out great amounts of damage makes him one of the most powerful X-Men.
- Chrome Champion: He has the ability to transform his body into steel-like substance, granting him superhuman strength and durability.
- Mutant: He is one with the ability to transform his body into steel-like substance.
- Nigh-Invulnerability: His armored form is extremely hard to damage.
- Super Strength: The one of the main powers that has in his armored form.
- What Happened to the Mouse?: Colossus appeared in the first episode as a team member, but never returned after the rest of the team was reunited. He was supposed to in Season 2, however.
Armando Munoz, also known as Darwin, is a mutant who appeared in the apocalyptic future. Darwin has the power of "reactive evolution"; i.e., his body automatically adapts to any situation or environment he is placed in, allowing him to survive possibly anything.
Alison Blaire, also known as Dazzler, is a mutant who chartered a boat to the mutant haven of Genosha. However, along the way the boat was attacked by Spiral and the Reavers and she was among those captured for use of her powers. The X-Man Nightcrawler saved them. They eventually made their way to Genosha. To celebrate, she performed a concert for the island nation. Dazzler has the ability to transforms sound into bolts of light.
Soraya Qadir, also known as Dust, is a mutant who was a captive of the Mutant Response Division. She and others are freed by Wolverine and Dust uses her mutant abilities to take out some MRD jets. Dust also appears on Genosha, where she informs Nightcrawler about Magneto's underground cells. Later on, she ends up in Magneto's underground cells as a prisoner. Dust has the ability to transform into and control a malleable sand form.
Fever Patch is a mutant who has a skeleton that is on fire and resided in Genosha.
- Flaming Skulls: He has one that is on fire.
- Mutant: He is one that looks like a burning skull and has the ability to project fire.
- Playing with Fire: He is able to project flames.
- Skull for a Head He has this.
- Technicolor Fire: The color of the fire that is surrounding his skeleton is blue.
- Wreathed in Flames: He has a skeleton that is on fire.
In the apocalyptic future, Angelica Jones, also known as Firestar, is a mutant who was a prisoner in a mutant prison camp before she escaped after Professor Xavier's arrival. She has the ability to project microwave energy, generating intense heat and fiery hair.
- The Cameo: She has a one in the episode "Future X".
- Elemental Powers: Her main mutant power is generating heat.
- Flaming Hair: This version of Firstar is also shown to have fiery hair when using her powers.
- Flying Firepower: As per usual. She has the ability to project microwave energy, generating intense heat and fiery hair.
- I Believe I Can Fly: She also has the mutant ability to fly.
- Mutant: She is one with the ability to generating intense heat and fly.
- Playing with Fire: As always with Firestar.
- Technicolor Fire: The color of her fiery hair is a mixture of yellow and red.
Remy LeBeau, also known as Gambit, is a mutant who is also thief for-hire. His primary mutant power is the ability to charge matter with volatile kinetic energy, which usually causes the object in question to explode when thrown. He generally uses playing cards for this purpose.
- Adaptational Villainy: Gambit, while also not part of the X-Men in the first place in this adaptation, is less noble than his comic book counterpart and willing to sell out mutantkind out in the name of money.
- Affably Evil: So long as it doesn't get in the way of his personal interests, he's quite sincere and polite even when there's no sign of manipulation.
- Badass Longcoat: Just like his comic book counterpart and most versions, Gambit wears a long coat with body armor.
- Batman Gambit: His plan to steal Magneto's helmet was to admit that he was sent there to steal Magneto's helmet so he could walk around freely thus he could have an easier time stealing Magneto's helmet. Turns out the helmet was just misdirection so that he could cripple their infastructure with a few well-placed explosives.
- Cane Fu: His particular style of bojutsu focuses on the use of a bo staff.
- The Charmer: He's very adept at sweet-talking others and can really pour on the verbal charm if he wants to.
- Charm Person: He has a degree of "hypnotic charm" that works on some females.
- Conspicuous Gloves: Gambit also wears gloves. His touch allows him to change the potential energy of objects he touches into kinetic energy; his gloves have a few fingers open or missing so he can "charge" and manipulate his cards (one of his weapons of choice). That said, the gloves' design is also cool.
- Deadpan Snarker: As always, every other sentence that comes out of his mouth is a snark.
- Enemy Mine: Wolverine does not get along with him, but Gambit is forced to work with him when being held at claw point for selling off a mutant power inhibitor. It goes as well as one would expect.
- The Gambler: As with most versions, Gambit energizes playing cards to explode on impact and tosses them with precision at his targets.
- Gentleman Thief: Subverted in that he's lovable but still a total sleaze who will sell out those who hinder him getting more money or finishing a job. When it comes to fulfilling a deal or saving his own skin as he was all too willing to let Wolverine get blasted for destroying his money even after he promised to pay him for another job.
- Glowing Eyes of Doom: His eyes have been known to give off red energy when he's intended to look particularly badass.
- Improbable Weapon User: The exploding playing cards, not the bo staff.
- Lovable Rogue: In addition to being a thief, he is this as well.
- The Magic Touch: He has the ability to turn anything he touches into an explosive. Although he prefers to charge and flick playing cards at his opponent.
- Noble Demon: The Thieves Guild has a Code of Honor which he sticks by.
- Only in It for the Money: Gambit makes it clear he doesn't care who he sides with as long as he gets paid handsomely.
- Paper Master: His playing card ammo.
- Poirot Speak: His Caijun French dialect.
- Playing Card Motifs: He has a playing card theme.
- Promoted to Love Interest: He never had a relationship with Polaris in the comics.
- Real Men Wear Pink: His classic magenta vest and his power's glow. Not to mention the playing cards he's seen with so far have pink-ish-colored backs.
- Red Oni, Blue Oni: Plays the Blue Oni to Wolverine's red, being the calmer planner going for the subtle approach, while Wolverine is perfectly fine with blindly charging in.
- Simple Staff: His collapsible adamantium bo staff.
- Truer to the Text: He is much more faithful to his comic book counterpart than the X-Men: Evolution version was.
- Trojan Prisoner: Gambit is able to get onto Genosha by admitting that Senator Kelly sent him there to steal Magneto's helmet. Turns out he's actually there to cripple their infrastructure and leave them open to invasion.
- Wild Card: Gambit's not above renegotiating his contracts under fire. And then bailing out once he gets what he wanted.
- What Happened to the Mouse?: It is unknown what happened to him after Polaris sank the boat in which he was using to leave Genosha.
Amara, also known as Magma, is a mutant who is a young white brazilian teenage girl. She was chased by the MRD, as part of Senator Kelly's plan to have a scene of "a mutant putting the public in danger". Wolverine places a power dampening collar created by Forge around her to save her. She later returns it to him as she boards an aircraft sent to pick her up. Magma has the ability to generate and projects bursts of heat and flames.
Sarah Vale, also known as Network, is a mutant on the way to Genosha, and after the Reavers attacked, she helped steer the ship with her powers to technologically learn how to. Network has the ability to converse with machines.
Robert Hunter, also known as Nitro, is a mutant who willingly accepts confinement in a government mutant prison run by the Mutant Response Division due to his lack of control over his incredibly destructive abilities. When the guards try to lock him in a cell, he resists saying he cannot be around other people. He then flees the building until he is far enough away to avoid harming anyone with the massive energy blast that follows. Nitro has the ability to emit energy explosions.
- Adaptational Heroism: Nitro releases giant explosions of energy whenever he's stressed, or just when enough energy is stored up. He willingly submits to confinement so he doesn't harm others, and is used by the villains as a blunt instrument against his will. In the comics, Nitro is a killer for hire, and caused both the death of the Kree Captain Marvel and the Stamford Incident that killed about 700-ish people with sadistic glee.
- Adaptational Species Change: He is portrayed as a mutant instead of a super powered human just like in the comics.
- Having a Blast: He has the ability to emit energy explosions.
- Mutant: In contrast to his comic book counterpart, this version of Nitro is portrayed a mutant with the ability to emit energy explosions.
- Too Powerful to Live: His power becomes so dangerous and unstable that the X-Men had to reluctantly put him back to sleep in the MRD facility.
Christy Nord, also known as Petra, is a mutant who is the daughter of Maverick (Christoph Nord). She has the ability to control and manipulate rock and earth.
- Canon Foreigner: She does not have a comic book counterpart.
- Expy: Her powers and physical appearance are based on those of the character named Petra (although Maverick does not have a daughter in the comics).
- Elemental Powers: She has the ability to control and manipulate rock and earth.
- Power-Strain Blackout: She faints after using her powers to save Wolverine and her father.
Megan Gwynn, also known as Pixie, is a mutant who was heading to Genosha. After the Reavers attacked, she helped save the ship from destruction. Pixie has the ability to fly with her mutant butterfly wings.
Betsy Braddock, also known as Psylocke, is a telepathic mutant who was captured by the Mutant Response Division and rescued by Quicksilver. When the Brotherhood of Mutants found Nitro, they asked Psylocke help control his powers. They wanted to transport him to Genosha to be used by Magneto. They were confronted by the X-Men and she was stopped by Emma Frost. Psylocke is able to listen to other people's thought. She can also fire psychic "bolts." She presents a butterfly-shaped energy aura whenever she is using her powers.
- Adaptational Villainy: While it was due to owing Quicksilver a favor, this Psylocke sided with the Brotherhood as opposed to the X-Men just like her comic book counterpart.
- Alliterative Name: Betsy Braddock.
- Animal Motifs: Butterflies, a symbol of her telepathy.
- Pet the Dog: Helped a woman and her kids who was having an argument with a female parking enforcement cop over ticketing her vehicle by making the cop rip up and eat the ticket and give her hat and notepad to each of the mother's kids.
- Psychic Powers: Psylocke has psychic powers that are presented through a butterfly-shaped energy aura.
- You Gotta Have Blue Hair: She has purple hair.
Shadow King/Amahl Farouk
Amahl Farouk, also known as Shadow King, is a powerful psychic mutant who used a young Ororo Munroe to steal for him before she eventually caught the attention of Charles Xavier, who fought Shadow King and sent his soul to the astral plane. Ororo became the X-Man Storm. Shadow King spent the years traveling across Africa to find her. He eventually did and possessed her. He convinced her that Africa was burning and she needed to put it out. She created a giant storm but the X-Men came to stop her. Thanks to Emma Frost, they were able to free her and destroy Shadow King since he did not have a body to live off.
- Arch-Enemy: To Storm.
- Black Eyes of Crazy: Those he possess display black eyes as a sign they're under his control.
- Badass Baritone: Due to his voice actor.
- Body Surf: Spent years hopping from body to body since his spirit cant survive without a host.
- Comic-Book Fantasy Casting: The voice Kevin Michael Richardson does seems to channel the voice Frank Welker did for Soundwave, Darkseid, and Dr. Claw.
- Dark Is Evil: His astral form consists of dark colors.
- Demonic Possession: This is his schtick, due to being a disembodied psyche.
- Killed Off for Real: Implied to have died off for good after his fight with Emma Frost that left him with no body to possess.
- Power Of Hate: His hatred of Storm allowed his spirit to persist after his body was destroyed and spent years surviving by jumping through host bodies just to find her and get his revenge.
- Psychic Powers: Prior to having has physical body destroyed, he had psychic powers.
- Stalker Without a Crush: In revenge for the destruction of his body and ruination of his theft business, Shadow King has spent years tracking down Storm so he can take over her body and use it to destroy Africa, all so Storm can no longer have a place to call home and wander aimlessly for the rest of her life.
- The Svengali: He originally had Storm and a number of young beggars steal for him as his slaves and property until Xavier appeared to rescue her and destroyed his physical body.
Silvr Samurai/Kenuichio Hirada
Kenuichio Hirada, also known as Silver Samurai, is the mutant son of the former Japanese crime lord Shingen Harada and husband of Mariko Yashida. As a youth, Harada mastered the attendant disciplines of the medieval samurai and sought employment as a warrior for hire. With enhanced tachyon energy, he uses his sword to cut through any known materials.
- Absurdly Sharp Blade: His mutant power gives his blade this kind of edge.
- Alliterative Name: Silver Samurai.
- Armour Is Useless: Averted. Harada's armour may not be made of adamantium, and is far from indestructible.
- Captain Ethnic: A Japanese villain with Yakuza ties, an obsession with honor, and a samurai theme.
- Cheaters Never Prosper: In his katana duel to the death with Logan, where they're not allowed to use their mutant abilities. Once Logan gets the upper hand on Silver Samurai, he blatantly cheats and uses his powers to beat him back. Just as Silver Samurai was about to deal the killing blow to Logan, he gets stopped and knocked out by the ninja referee. Because he broke the no powers rule, in front of witnesses, he loses by default.
- Color Character: The Silver Samurai.
- Composite Character: He is merged with Noburu Hideki, Mariko's fiance from the original Frank Miller Wolverine mini-series. This causes a bit of Squick, since Silver Samurai is Mariko's BROTHER in the original comics.
- Chest Insignia: He wears the Imperial Japanese flag on the chest of his armor.
- Domestic Abuse: Its implied Hirada physically abuses Mariko in their marriage especially since he was about to strike her for saying he would lose against Logan in a duel to the death before changing his mind.
- Evil Is Petty: Hirada never loved Mariko. He specifically stated to Logan the reason why he married her was so that Logan couldn't.
- Green-Eyed Monster: Hes hatefully jealous of Logan for defeating him and only married his then love Mariko so that Logan couldnt and admitted Mariko personally means nothing to him.
- Katanas Are Just Better: Naturally, the Silver Samurai prefers a katana sword over any other weapon, and his mutant powers enhance their deadliness to let him pull this off in-universe.
- Samurai: Dresses as a samurai, though his armor is forged of modern materials.
- Yakuza: He has some dealing with them.
Sammy Pare, also known as Squidboy, is a boy whose genetic mutation caused him to physically resemble a fish. He and his mother wererefugees on a ship bound for the mutant safe-haven Genosha along with Network, Pixie, Shatter, and other unnamed mutants. He befriended Nightcrawler on the ship. Squidboy and the others are assisted by Nightcrawler when they are attacked by the ship crew and later, Spiral and her Reavers from the Mojoverse. His underwater ability came in handy when it came to helping Nightcrawler repair the ship. Squidboy also infiltrated Spiral's ship. When Spiral threatened Squidboy, Nightcrawler rescued him and Squidboy and the other mutants were once again bound for Genosha. He has the ability to breathe and swim underwater.
- Amazing Technicolor Population: He has red colored skin.
- Fish Person: He resembles a fish.
- Heart Is an Awesome Power: His ability to swim and breath underwater makes him invaluable while rescuing his mother from a pirate ship and is lampshaded by Nightcrawler who mentions how important his power is on a cargo ship.
- Mutant: He is one that resembles a fish and has the mutant ability to breathe and swim underwater.
- Super Not-Drowning Skills: He has the mutant ability to breathe and swim underwater.
Shatter is a mutant who was a refugee that was heading to Genosha. He has the ability to change into a crystalline form and can shatter objects when he is in contact with them.
Tildie Soames is a young mutant girl who was locked up by the M.R.D and rescued by the X-Men. She has the ability to manifest her own nightmares and could bring her dreams to life.
Vindaloo is a mutant who was among the mutants that were on board on a ship to Genosha. He has the ability to generate sticky goo from his hands.
- Abnormal Ammo: The sticky goo that he shoots.
- Adaptation Dye-Job: In the comics, Vindaloo has black hair. Here, his hair is blonde.
- Adaptational Super Power Change: Vindaloo in the comics has pyrokinetic mutant powers that ignite when he makes contact with the air. In this show, he has the ability of generating stick goo.
- Mutant: He is one with ability to shoot sticky goo.
- Sticky Situation: His mutant power to generate sticky goo from his hands.
- Younger and Hipper: In the comics, Vindaloo is an adult. Here, he is a teenager.