The X-Men were alerted to the existence of the Morlocks after Callisto, their leader, kidnapped the X-Man Angel and intended to make him her mate. The X-Men realized they could not rescue Angel without ruling over the numerous Morlocks. This brought Storm to challenge Callisto to a duel. The prize of the duel was to become the leader of the Morlocks. Storm, feeling that she should be the one to duel Callisto (as leader of the X-Men) defeated her in hand-to-hand combat. She rescued Angel and became the de facto leader of the Morlocks. Against her wishes, the Morlocks later kidnapped the child superheroes Power Pack so that they could be raised by the Morlock Annalee, who had lost her own children. When Power Pack confronted Annalee, she let them go willingly. They promised to return in the future to keep her company. A majority of the Morlocks were slaughtered by Mister Sinister's Marauders in the Mutant Massacre. Most of the few survivors moved on to join Gene Nation, having lived in a pocket dimension led by Mikhail Rasputin. While other survivors of the massacre ended up elsewhere, such as Leech and Artie - who became wards of Generation X; Erg and Beautiful Dreamer - whose whereabouts was unknown until Decimation; Thornn - who would join X-Corporation and Caliban. It is later revealed that many of the Morlocks were actually failed experiments of the Dark Beast, which is why Mr. Sinister sought to destroy them, seeing his handiwork in them. Recently, a new group which calls itself "Those Who Live in Darkness" have inhabited the sewer tunnels just below the surface of Mutant Town/District X.
Debuting along with the rest of the Morlocks (with the exception of Caliban it was revealed that Masque, Caliban, Callisto and Sunder founded the Morlocks under the streets of Manhattan.
- Dark Beast - Creator of the Morlocks. Formerly from the Age of Apocalypse and the Brotherhood. Infiltrated the X-Men for a time posing as the original Beast. Although not classed as a Morlock, he sees himself as their creator and has been called the "first one" by members of Gene Nation. Recently been recruited by Norman Osborn as scientist and member of Dark X-Men.
- Masque - Former leader after the Mutant Massacre. Led a splinter group for a time called the Tunnelers. Impaled by Shatterstar's sword but was revealed alive. Leader of the Morlocks once again.
- Callisto - Former leader of the Morlocks. Arms were turned into tentacles by Masque. Aided Magneto and Professor X in Genosha. Depowered. Former member Of X-Cell; current whereabouts unknown; however, she is the current leader following M-Day.
- Caliban - Caliban became Death, and later Pestilence. Served on the X-Force for a time. Joined the X-Men after Decimation; killed by the Purifiers saving James Proudstar. Resurrected by Eli Bard.
- Sunder - Joined the impromptu Muir Island "X-Men" team. Shot by Pretty Boy of the Reavers
- Plague - Became Pestilence, one of the Horsemen of Apocalypse. Died after falling off her flying horse.
- Storm - Defeated Callisto in a duel to become the Morlocks' leader, although not classed as one. Former X-Men and Fantastic Four member; current queen of Wakanda.
- Jo - Only appearance as a Morlock was her debut issue as Kitty Pryde's bridesmaid. Current whereabouts unknown.
- Leech - Has been in the first few incarnations of the Morlocks. Adopted son of Annalee. Formerly of X-Terminators and Generation X. Captured by the Weapon X program and used as the Neverland power damper, He is assumed to be one of the 198 who retain their mutant powers after the House of M; used by Masque because of the prophecies of Qwerty.
- Healer - He burned himself out to heal and restore Callisto.
- Piper - Controlled animals using music. Killed by the Marauders.
- Erg - Electrical blaster. Erg was a painter before becoming a Morlock. He is one of the 198; joined Masque's current incarnation.
- Ape - Shapeshifter. Captured by the Weapon X program and sent to the Neverland concentration camp and killed
- Tar Baby - Secretes adhesive. Captured by the Weapon X program and sent to the Neverland concentration camp and killed
- Annalee - Emotion projector. Adopts Leech. Shot by Scalphunter in the Mutant Massacre.
- Beautiful Dreamer - Altered memories of those "recruited" as Morlocks. Believed killed in the Mutant Massacre, but listed as alive and powered post-M-Day.
- Skids (Sally Blevins) - Resented because she was seen as the prettiest of the Morlocks (her force field protected her from scars and Masque's powers). She left them and became a ward of X-Factor. After M-Day, she became a follower of Apocalypse and is friends with Scalphunter. Was part of Masque's new group of Morlock Extremists, as a spy for SHIELD.
The Mutant Massacre was one of Marvel's annual crossovers events, centering on the Morlocks. The event resulted in the Marauders killing many of the Morlocks under orders of Mr. Sinister. Protected by the X-Men, X-Factor, Power Pack and Thor, only few survived. The event spanned Uncanny X-Men #210-212, X-Factor vol. 1 #9-11, New Mutants vol. 1 #46, Thor vol. 1 #373-374 and Power Pack vol. 1 #27. Many new Morlocks were also debuted, although many were killed in their first appearance.
- Tommy - Shot by Scalphunter, after she accidentally led the Marauders to the entrance to the Morlocks' home; however it was later revealed that this was Gambit's doing.
- Cybelle - Acid-secreting Tunneler killed by Harpoon.
- Zeek - Killed by Harpoon.
- Scaleface - Formerly part of Masque's splinter group, the Tunnelers. Shot by the police in her reptile-form
- Berzerker - Formerly part of Masque's splinter group, the Tunnelers. Killed by electrocuting himself with his own powers
- Blowhard - Formerly part of Masque's splinter group, the Tunnelers. Shot by a local gang
Most of the surviving Morlocks relocated themselves throughout New York City after the massacre. Few, however, returned to the Alley, their original home. There, Masque assumed leadership. Many new surviving Morlocks were introduced when Sabretooth decided to finish his original task. He is stopped by a newly "upgraded" Caliban. Later, a splinter group of the Morlocks is introduced. This group, led by Pixie, is attempting to escape Masque.
- Lightning Bug - Killed in the Mutant Massacre. Astral essence survived and searches out a new form to inhabit. Her essence later perished
- Chickenwings - Killed by Sabretooth.
- Mole - Could tunnel through solid matter. It is strongly implied that Mole was killed by Sabretooth
- Bliss - Has the power of a poisonous bite. Currently part of Masque's new group of Morlock Extremists.
- Bouncer - mass teleporter; current whereabouts and status unknown.
- Samson - Killed by Sabretooth
- Brute - Shot by Cable
- Hump - Brute's brother; current whereabouts and status unknown.
- Pixie - Led a splinter group of Morlocks on the run from Masque. Murdered by Blackout
- Bertram - current whereabouts and status unknown.
- Feral - Left the Morlocks. She was depowered as a result of Decimation but recently she regained her physical mutation, only to be killed by Sabretooth.
- Pester - Daughter of Mother Inferior; current whereabouts and status unknown.
- Ent - current whereabouts and status unknown.
- Mother Inferior - Crushed by falling debris
- Thornn - Left the Morlocks after the Great Flood. Depowered as a result of Decimation but regained her physical mutation again.
With Masque presumed killed, an insane Mikhail Rasputin takes over as leader of the Morlocks in Uncanny X-Men #293. As leader, he then floods the tunnels in order to destroy the remaining Morlocks. It is revealed later that he actually transported the Morlocks to another dimension dubbed the Hill, whose timeline moved faster than the main Marvel Universe. There, he set himself up as their king and forced them to fight for the right to live.
- Alex - current whereabouts and status unknown.
- Mikhail Rasputin - Former leader of the Morlocks. Transported them to the Hill dimension. Currently is in 'The Dark Zone.
- MeMe - Mind shut down by Jean Grey to rescue humans he absorbed.
- Monte - current whereabouts and status unknown.
- Brain Cell - current whereabouts and status unknown.
- Marrow - One of the Morlocks that were transported to the Hill dimension by Mikhail Rasputin. Returned to lead a terrorist faction known as Gene Nation. Seemingly killed by Storm. Revealed to have survive with the help of a second heart. Formerly of the X-Men, SHIELD and Weapon X Program. Only Gene Nation member who was a real Morlock (not being born in The Hill). Depowered; later joined X-Cell.
- Marilou - Killed by Mikhail Rasputin.
With the Morlocks presumed dead by the floods caused by Mikhail Rasputin, some of the remaining Morlocks were relocated to Selima Oasis in North Africa. When attacked by Humanity's Last Stand, an emotional backlash caused D'Gard to assume control over Storm, who relinquished her leadership role. In X-Men: Prime many of the Hill Morlocks returned to found Gene Nation. As the new group, they attacked the human oppressors of the past Morlocks under the leadership of Marrow. It is unknown whether the remaining Morlocks of Africa stayed there or relocated to New York. A few have been seen there since, as well as a few Morlocks who chose to remain in New York despite previous attempts on their lives.
- Boost - One of the many surviving Morlocks. Relocated to North Africa but defected to the Brotherhood. Depowered.
- Tether - One of the many surviving Morlocks relocated to North Africa. Defected to the Brotherhood. Depowered.
- D'Gard - Became leader of the Morlocks while in North Africa when he made Storm relinquish her leadership. Killed by Marrow as a sign of loyalty to the new Weapon X program
- Revelation - Revealed to have been in suspended animation around the time of Storm's becoming the Morlock leader as a result of her death-powers. Died in the Punisher's arms
- Soteira - Revealed to be around at the time Storm became Morlock leader. Was the scientist that put Revelation in suspended animation. Appeared as a hologram telling Wolverine and the Punisher she will die as a result of prolonged exposure to Revelation's powers
- Carver - Leader of a splinter group of five Morlocks who survived the Massacres and the Flood and who still followed the old Morlock rules.
- Fugue - Member of the splinter group of five who still follow the old Morlocks rule.
After M-Day, Some former Morlocks who lost their powers were Angel Dust, Boost, Irving, Qwerty, Delphi, Callisto, Marrow, Postman, Shatter, Tether and the probability of Feral and Thornn. However, Feral and Thornn were later seen re-powered; but this was later to be revealed in Wolverine (vol. 3) #54-55 that only their physical mutations were restored, not their mutant powers, which led to Feral being killed by Sabretooth. In one of Generation M's "Ex-Mutants' Diaries," Sally interviews Marrow about the Morlocks. Marrow reports that 80% of the remaining Morlocks (which was most likely already very small) are depowered now and look like humans. She states that most of them are still afraid about going out of the tunnels. Currently, Marrow works as a watchmen of the Morlocks, as she is called by the remaining ones when problems occur. She explained this status in the aftermath of thirteen depowered Morlocks murder by Ghoul. One character commented that, post-M-Day, the chance of meeting a Morlock in the tunnels under New York is now harder than meeting an alligator in the Floridian sewers. Some former Morlocks who actually kept their powers sought refugee at Xavier's Institute and became known as 198. They are Beautiful Dreamer, Caliban, Erg, Leech, and Skids. Dark Beast and Mikhail Rasputin are also still powered, though Mikhail is in The Dark Zone.
During Ed Brubaker's "The Extremists" arc, the Morlocks reappear under the leadership of Masque and now consisting of Bliss, Erg, Litterbug, Skids and a recently captured Leech. Later in this story it was revealed Skids only joined the Morlocks to spy on them on behalf of S.H.I.E.L.D.
All Current Morlocks Shown After M-Day
All Powered =
- Skids - currently with S.H.I.E.L.D.
- Beautiful Dreamer - killed by new form of Legacy Virus
- Leech - presumably with X-Men in San Fransisco
- Caliban - was deceased, currently re-animated by Eli Bard and Selene
- Erg - arrested after riots in Utopia
- Bliss - presumably in tunnels
- Litterbug - presumably in tunnels
- Masque - current whereabouts unknown
- Sack - killed by nimrod
- Fever Pitch - killed by new form of Legacy Virus
All Depowered =
- Callisto - depowered, currently in tunnels
- Marrow - depowered, currently in tunnels
- Thornn - depowered, physical mutations restored, current whereabouts unknown
- Feral - depowered, physical mutations restored, later killed by Sabretooth, then returns as a ghost
All Powered Former Leaders Not Currently Involved With Group =
- Storm - currently with X-Men
- Mikhail Rasputin - trapped in other dimension
- Dark Beast - currently with Dark X-Men
- Delphi - last seen in explosion, never seen again.
- Marked Man - imprisoned and never seen again.
- Obsidian - last seen in explosion, never seen again.
- Tobe - last seen fighting Storm, never seen again.
- Membrain - last seen in explosion, never seen again.
- Monte - last seen during the flood, never seen again.
- Brain Cell - last seen during the flood, never seen again.
- Ever - last seen attacked by Dark Beast never seen again.
- Integer - last seen in explosion, never again.
- Fugue - last seen falling into a chasm, never seen again.
- Carver - last seen falling into a chasm, never seen again.
- Pester - last seen living with homeless humans, never seen again.
- Ent - last seen living with homeless humans, never seen again.
- Bertram - last seen during the flood, never seen again.
- Eva - last seen with Wolverine, never seen again.
- Boost - dropped off in africa, never seen again.
- Tether - dropped off in africa, never seen again.
- Charm - dropped off in africa, never seen again.
- Shatter - depowered hasn't been seen after m-day, never seen again.
- Postman - depowered hasn't been seen after m-day, never seen again.
- Angel Dust - depowered hasn't been seen after m-day, never seen again.
Morlocks that are still alive.
- Callisto - living underground.
- Storm - with X-Men.
- Litterbug - living underground.
- Marrow - living underground.
- Bliss - living underground.
- Skids - living underground.
- Artie Maddicks - living underground.
- Leech - living underground.
- Electric Eve - living underground.
- Danna Moonstar - from another reality.
- Feral - left the Morlocks now a ghost wondering earth.
- Thornn - left the Morlocks.
- Erg - living underground.
- Masque - living underground.
- Spyke - only appeared in the cartoons.
- Torpid - only appeared in the cartoons.
- Facade - only appeared in the cartoons.
- Lucid - only appeared in the cartoons.
- Marianna - only appeared in the cartoons.