The mutant Leech can negate the special powers of those around him, leading to a lonely life until he finds friendship and a home with team X-Factor.


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The lonesome Leech is relegated to an underground existence, cast out by society because of his mutant appearance and powers, until X-Factor takes him in as a ward where he flourishes by helping people.


An Outcast

While still a boy, Leech is presumably abandoned by human parents due to his misshapen, green-skinned mutant appearance. He’s discovered by the mutant-detecting Caliban, who brings him to Callisto, leader of the outcast Morlocks mutant community, who live in a long-abandoned network of tunnels deep below New York City. However, Leech’s power-dampening aura and appearance ostracizes him, and he’s forced to live apart from the Morlocks in the tunnel system’s ceilings and outskirts. Possibly due to his lack of interaction with others, or lack of education, Leech speaks in fractured phrases, single words, and in third person.


Like a Leech

Leech casts a power-dampening aura, which temporarily negates superhuman abilities, mutant or otherwise. Initially uncontrollable, Leech eventually learns to expand his aura to 30', or to condense it to a few inches from his body through concentration. Leech can depower a mutant after he touches them for up to five minutes even if they leave his proximity. Leech’s aura does not work when he is unconscious; it cannot be absorbed by Anna Marie, AKA Rogue’s power absorption abilities, instead rendering her temporarily powerless; and Tyrone Johnson, AKA Cloak’s Darkforce abilities are not affected; it also makes telepathically contacting or tracking Leech impossible.

Leech sometimes wears an image inducer upon his wrist that allows him to cast holograms over himself, to appear as any person programmed into it.

Though his skull was initially elongated and he only had three fingers, Leech currently has a more human-shaped head and four fingers, possibly due to continued mutation through puberty.


Fearsome Foes

Unfortunately for Leech, he’s been the target of many who seek to harm him or use him for his powers. Such foes have included the Marauders, the anti-mutant Right organization, and demons, and even members from Gene Nation, former Morlocks who escaped the Mutant Massacre and thought Leech a disgrace to their kind.


Found Family

Due to Leech’s appearance, he’s abandoned by his biological family and then, he’s ostracized from the Morlocks community due to his ability to negate others’ powers. This repeated rejection leaves him lonely but he soon relates to fellow Morlock Annalee after her children are murdered. Though she also rejects him at first, and is altogether unkind to him, she ultimately accepts him as a surrogate child.

Leech becomes close friends with the X-Factor’s ward Artie Maddicks when they’re evading the killer Victor Creed, AKA Sabretooth. Subsequently, Annalee was murdered during the Mutant Massacre by the Marauders, and X-Factor takes Leech on as their ward. Leech becomes close with Jean Grey, AKA Phoenix. He and Artie eventually attend Vermont’s St. Simons Academy where they meet and befriend techno-morph Takeshi Matsuya, AKA Wiz Kid. Leech and Artie also befriend the psionic and reality-manipulating Franklin Richards.

Leech uses his powers to help many mutants when their powers are uncontrollable, such as Julio Richter, AKA Rictor, and Bobby Drake, AKA Iceman, and Scott Summers, AKA Cyclops. Leech eventually joins Generation X, the Daydreamers, and the Fantastic Four’s Future Foundation.


Carving Out His Place in the World

Lost in the tunnels after being kidnapped by the Morlocks, X-Man Kate Pryde encountered Leech, who brought Pryde back to the Morlock community, then temporarily depowered the X-Men who came to rescue her. Sometime later, projecting empath Morlock Annalee’s children were murdered by John Greycrow, AKA Scalphunter (later Greycrow); Leech related to her loneliness, but she rejected him over his appearance. Wanting to make her happy, Leech depowered the Power Pack children to help Annalee’s bid to kidnap them as surrogate children. While imprisoned, a stray kitten Power Pack had rescued befriended Leech. Julie Power took the kitten from Leech to lead him away from her siblings so they could regain their powers and fight Annalee’s friends, the Drain Dwellers (a Morlock sub-group). After talking to Leech, Julie sympathized with Annalee’s sadness and tried unsuccessfully to get her to accept Leech, although she was momentarily convinced the Powers parents would miss their children as much as she missed her own and let them go. Feeling bad for Leech, Power Pack gave him the kitten so he wouldn’t be so alone.

However, Annalee kidnapped the Power kids again, and when the X-Men came to rescue them, Leech was knocked unconscious when he touched the power-stealing Rogue. Other Morlocks planned to kill Leech and frame Rogue, but the X-Men helped rescue Power Pack before Leech could be harmed. Forgiving Annalee, Katie Power invited her to Thanksgiving at the Powers' home, but when Leech tried to accompany Annalee, she locked him in a crate to prevent him from going. When Leech escaped and followed her, she used her projecting empathy to make parade spectators attack him, but he was saved by Alex Power and Cloak and Tandy Bowen, AKA Dagger. Seeing Leech still cherished her despite her cruelty, Annalee accepted him as a surrogate child, won over by his unconditional love. After dinner, Jack Power gave Leech some of his old clothing, and Annalee took him home.

When Nathaniel Essex, AKA Mister Sinister’s Marauders began slaughtering the Morlocks, Artie Maddicks—young mutant and ward of the heroic X-Factor/X-Terminators—looked for his friend and fellow ward Rusty Collins in the Morlock tunnels. Artie met Leech, and the two quickly became fast friends, helping each other avoid being harmed by the murderous Sabretooth. After Artie left to find his friends, Leech protected the injured Caliban until they were rescued by Power Pack, but he was devastated to learn Annalee had been killed. X-Factor took Leech in as their ward, where he was happily reunited with Artie and became especially close with Jean Grey, AKA Phoenix.

Leech helped keep other mutants’ powers in check when they would become uncontrollable, such as Rictor and Iceman, frequently stopped fights between mutants, and began learning how to master his own power. Leech and X-Factor’s wards were kidnapped by the anti-mutant Right organization, but were rescued by X-Factor before the Right could weaponize them. When celebrating his first Christmas, Leech convinced all his fellow wards to donate their gifts to children hospitalized due to a battle between X-Factor and En Sabah Nur, AKA Apocalypse.

Artie and Leech were eventually sent to Vermont’s St. Simons Academy boarding school, but were soon kidnapped by demons seeking mutant baby sacrifices to empower a demonic invasion of New York City (“Inferno”). They were rescued by X-Factor’s wards (Rictor, Rusty, Tabitha Smith, AKA Boom Boom, Sally Blevins, AKA Skids, collectively calling themselves X-Terminators) and fellow St. Simons student, Wiz Kid. During the crisis, Leech and Artie helped care for the kidnapped babies, then returned to school. Visited periodically by members of X-Factor, Artie, Leech, and Wiz Kid all found acceptance at St. Simons and took part in school plays but were all injured while opposing the Alliance of Evil when they attacked the school while on assignment for Advanced Idea Mechanics (A.I.M.).

While joyriding in Wiz Kid’s flying saucer creation, the kids were photographed by Ida Fassbender and unknowingly mistaken for aliens. Seeing Fassbender speak of aliens on the news, Leech thought she resembled Annalee and wanted to help relieve her fears. When they went to her house, Fassbender was initially terrified of the kids, but after learning they were mutant children, not aliens, she prevented police from taking them into custody and allowed Leech to consider her his special “Grammie.”

When Charles Xavier, AKA Professor X, opened a branch of his school for mutant youngsters in the Massachusetts Academy, he arranged to transfer Artie and Leech there. However, when the boys went to New York City to be picked up by school headmistress Emma Frost, they were attacked by members of Gene Nation, Morlocks who escaped the Morlock massacre by fleeing to another dimension that hardened and aged them; they wanted to kill Leech for being a representative of the weak, embarrassing Morlocks they once were. To regain her telepathy and defeat them, Frost brutally kicked Leech unconscious, disabling his power-dampening field.

Once at the Academy, fellow students Angelo Espinosa, AKA Skin, and Everett Thomas, Synch, built a tree house in the fully interactive biosphere terrarium for Artie and Leech to live in; the two boys liked their new home so much, they rarely left it.

When the Fantastic Four’s Reed Richards, AKA Mister Fantastic, and Susan Storm Richards, AKA Invisible Woman, were believed dead, their son, Franklin, stayed at the school for a time, becoming close with Artie and Leech. School headmaster Sean Cassidy, AKA Banshee, took the three boys to celebrate Halloween in Rutland, Vermont, and members of the X-Men took them to visit X-Man Beast’s childhood farm, where Leech helped depower Franklin when his powers briefly went out of control. During Tom Cassidy, AKA Black Tom’s attack upon the Academy, Artie, Leech and Franklin were teleported to safety by Ted Sallis, AKA Man-Thing, along with the visiting extradimensional Howard the Duck and extraterrestrial Tana Nile, but Franklin’s powers inadvertently diverted them into multiple pocket realities based on his subconscious, which the six “Daydreamers” explored before returning to the Academy.

After the school was opened to human students, Artie and Leech were moved into a renovated attic, which they turned into their dream living quarters and playroom. To leave the attic, Emma Frost gave them image inducers, which allowed them to holographically disguise their mutant appearances, and gave them strict instructions they were not to be used as toys, but the boys soon ran amok as cartoony versions of Spider-Man and Victor Von Doom, AKA Doctor Doom, earning reprimands from Frost. When Frost included them on a field trip to Manhattan, Artie and Leech became bored with the museum itinerary and ran away to visit Franklin, who had since returned to the Fantastic Four after they were discovered alive. The boys presented themselves as dual Spider-Men, distracting William Baker, AKA Sandman, long enough to prevent Peter Parker, AKA Spider-Man, from being beaten by him, then caused a small teenage girl mob after appearing as members of a popular boy band. They tried to enter Avengers Mansion by appearing as Steve Rogers, AKA Captain America, and Thor Odinson, AKA Thor, but were captured by the Avengers, then detained until an angry Frost could retrieve them.

After this, the boys remained at the Academy until an anti-mutant bombing resulted in Synch’s death and the closing of the Academy. Leech was later separated from Artie when he was captured by the clandestine Weapon X program and used to depower mutants, allowing Weapon X to perform selective genocide on mutants in the Neverland concentration camp; Leech was nearly killed by the depowering technology he was used to enable.

After Neverland shut down, Leech somehow escaped Weapon X and was later one of the few mutants to retain their power after an insane Wanda Maximoff, AKA Scarlet Witch, stripped most of mutantkind of their abilities. He joined refugee mutants (the 198) seeking the X-Men's protection at Xavier’s New York Institute, only to become near-prisoners of the United States government, who confined the mutants to the grounds using robotic Sentinel enforcers. Perhaps reminded of his Neverland incarceration, Leech accompanied mutants who escaped the Sentinels’ “protection,” hiding in Nevada for a time, and later saved Cyclops’ life by depowering him when his optic blasts raged uncontrollably; Leech and the other refugee mutants eventually returned to Xavier’s when they were promised voluntary residence.

After being reunited with Caliban in Manhattan, Leech was kidnapped by the remaining Morlocks, who were terrorizing the surface world while following a Morlock prophecy; Leech was rescued by the X-Men, who defeated the Morlocks after they were depowered by Leech. Artie and Leech were later invited to Franklin’s birthday party, where they were asked by Reed Richards to move in with the Fantastic Four and be a part of Richards’ Future Foundation, an organization dedicated to making the world a better place for tomorrow’s children; both boys accepted.

While with the Future Foundation, he helped the poisonous Jennifer Takeda, AKA Hazmat, who produces and absorbs radiation which relegates her to a protective suit. Leech’s powers allow Jennifer to enjoy a day outside, existing among people without her suit, and see her parents.

He later joins his fellow mutants on the independent island nation-state of Krakoa, where he trains in a place called the Quarry and wins in single combat against his friend Artie.




120 lbs.




Solid white (no visible pupil)



Universe, Other Aliases, Education, Place of Origin, Identity, Known Relatives, Group Affiliation
  • Universe

  • Other Aliases

  • Education

  • Place of Origin

  • Identity

  • Known Relatives

  • Group Affiliation