Published April 24, 2024

Meet Bastion, the Anti-Mutant Master of Sentinels

Who is Bastion? Meet the X-Men villain who blends man with machine and exercises total control over technology in his bid to eliminate mutantkind.

From mutant-hunting Sentinels to mutant-hating humans, the X-Men have faced and defeated dozens of villains who wanted to exterminate mutantkind. Even after the X-Men's greatest victories, some of these threats lingered… and found new life in Bastion. Where most Sentinels are towering robotic behemoths, Bastion blurs the line between man and machine, taking a more insidious approach in his agenda for mutant extinction. 

As the mastermind behind anti-mutant attacks like Operation Zero Tolerance, Bastion has acted as a key general in the war on mutants. He drafted unsuspecting humans to be his merciless Prime Sentinels, orchestrated the deaths of some of the X-Men's most iconic members, and turned long-dead enemies into present-day threats. Now, let's take a closer look at Bastion and how his plans almost eradicated mutantkind.


Bastion debuted as a mystery lingering around the edges of the X-Men's world. Just as the darkest aspects of Professor X and Magneto evolved into the villainous Onslaught and began attacking the Marvel Universe, Bastion surfaced in X-MEN (1991) #52 by Mark Waid and Andy Kubert. By his first full appearance in UNCANNY X-MEN (1963) #333 by Scott Lobdell and Pasqual Ferry, Bastion was already trying to sell government officials on Operation: Zero Tolerance, his plan for a worldwide crackdown on mutants.

Although his true origin remained a mystery for some time, Bastion is a fusion of the Master Mold—a Sentinel that builds other Sentinels—and Nimrod, an endlessly adaptable Sentinel from the future. After Master Mold absorbed Nimrod and was pushed through a mystical portal called the Siege Perilous, Bastion emerged on the other side with a human appearance, transformed into an amnesiac Sentinel hybrid with a super-strong cybernetic body and the ability to interface with and control various types of technology. After he was taken in by the kindly Rose Gilberti and given the name Sebastion, he fell in with mutant-hating groups like the Friends of Humanity


In the OPERATION: ZERO TOLERANCE crossover, Bastion enacted his plans to capture and eradicate as many mutants as possible with government approval. After the Fantastic Four and most of the Avengers disappeared fighting Onslaught and the mutant-hating politician Graydon Creed was assassinated, Bastion was able to use the surge in mutant hate to launch Operation: Zero Tolerance in X-MEN (1991) #65 by Scott Lobdell and Carlos Pacheco

The key to Bastion's plot was the Prime Sentinels, who were regular humans he transformed into formidable Sentinel sleeper agents using nanotechnology. Most notably, Bastion turned Karima Shapandar into the Omega Sentinel, a particularly powerful Prime Sentinel who later joined the X-Men before playing a significant role in the anti-mutant group Orchis

With Professor X already in custody after Onslaught, Bastion captured Jubilee and unsuccessfully tried to get her to give up information on the X-Men. Bastion and his Prime Sentinels attacked the X-Men directly and captured several critical members, like Cyclops, who had a bomb planted in his chest. Despite the best efforts of Cable and Caliban, Bastion also took over the X-Mansion and seized its considerable files on mutants. 

However, Operation: Zero Tolerance met opposition from several unlikely sources. J. Jonah Jameson and The Daily Bugle investigated Bastion, who killed one of the reporters researching him. After some time away from the X-Men, Iceman returned and confronted Bastion with the shield-generating Doctor Cecilia Reyes and Marrow, a militant former member of the Morlocks. After the reformed anti-mutant politician Senator Robert Kelly convinced the government to pull support for Operation: Zero Tolerance, S.H.I.E.L.D. forces stopped Bastion, who surrendered peacefully in X-MEN (1991) #69 by Lobdell, Pacheco, and Salvador Larroca.


Even though Operation: Zero Tolerance ultimately failed, Bastion remained a looming threat to the X-Men's world. After escaping from S.H.I.E.L.D., Bastion watched agents gun down Rose. He then tried to turn X-51, the Machine Man, into a new ultimate Sentinel using the remains of Master Mold in CABLE/MACHINE MAN ANNUAL (1998) #1 by Michael HigginsKarl Bollers, and Rick Leonardi. However, Cable teamed up with the robotic hero to stop Bastion, who then revealed his origins to the duo. 

During the era when Wolverine was brainwashed into serving as Apocalypse's Horseman of Death, he destroyed Bastion's body, leaving him as a cybernetic head. Bastion's head briefly fell into the custody of Mainspring, a cyborg who studied the techno-organic alien Phalanx and their Transmode Virus. 

After being infected by the techno-organic virus, Bastion briefly transformed into Template. He was ultimately defeated by the former New Mutants Warlock and Wolfsbane when he tried to summon an alien invasion force. Bastion's head fell back into government custody, where he used fake holographic simulations to mislead a small group of X-Men looking to recover the X-Mansion's files by seemingly revealing their teammates' secrets.


After gathering dust in government custody for years, Bastion returned and began a new effort to exterminate all mutants in X-FORCE (2008) #1 by Christopher YostCraig Kyle, and Clayton Crain. The Purifiers, a mutant-hating group inspired by William Stryker, recovered Bastion's head and connected it to Nimrod's body. With this Nimrod body, Bastion developed several new abilities, including the power to change his appearance, teleport, and travel through time. After taking charge of the Purifiers, he used them to recover a sample of a Phalanx alien and the Transmode Virus.

Believing that no one alive could stop mutants, Bastion used the techno-organic virus to resurrect several well-known mutant killers to follow him as the Human Council in X-FORCE (2008) #3 by Kyle, Yost, and Crain. This group of resurrected human and cyborg villains included anti-mutant ideologues like William Stryker, Graydon Creed, the Leper Queen, Cameron Hodge, and Sentinel developers Bolivar Trask and Stephen Lang. 

Under Bastion's orders, several mutants were captured and infected with a modified version of a mutant plague called the Legacy Virus. To stoke anti-mutant sentiment, they planned to release these mutants in crowds of humans while their powers overacted and killed anyone around them. Although X-Force saved several mutants, Bastion's plan ultimately worked after these attacks killed over 1,000 humans.


With most of the world's mutants already depowered after HOUSE OF M (2005), Bastion carried out his most successful attack during X-MEN: SECOND COMING (2010). When mutantkind gathered on the island Utopia, Cable returned to the present-day with Hope Summers, a "mutant messiah" who was considered the key to jumpstarting the stagnant worldwide mutant population. As part of their plan, the Human Council tried to kill or neutralize all of the X-Men with teleportation abilities, and Bastion personally killed Nightcrawler in X-FORCE (2008) #26 by Craig KyleChristopher Yost, and Mike Choi

Once the X-Men and their allies were isolated on Utopia, Bastion activated an impenetrable energy dome around the island and nearby San Francisco. In order to exterminate mutants permanently, Bastion opened a portal to Earth-811, Nimrod's apocalyptic timeline, allowing waves of Nimrod Sentinels to fly into the Marvel Universe every five minutes. 

Although X-Force successfully traveled to that alternate dimension and shut down the Nimrod-making Master Molds, Cable died bringing that team back home. Enraged by her adoptive father's death, Hope obliterated Bastion and his remaining allies in X-FORCE (2008) #28 by Kyle, Yost, and Choi.


Despite his apparent death, Bastion survived and saw a future where mutants were nearly eradicated by the Inhumans' Terrigen Mists. However, he realized he needed mutants alive to carry out his core mutant-hunting programming. As a result, he decided to save mutants in the present so he could exterminate them personally later on. 

Bastion tried to recruit time-displaced versions of the original X-Men in X-MEN: BLUE (2017) #3 by Cullen Bunn, Jorge Molina, and Ray-Anthony Height. However, the teenage mutants saw Bastion's true intentions and defeated him. 

Bastion also formed an unlikely alliance with Emma Frost, a villainous Havok, and Miss Sinister, a female clone of Mister Sinister, in X-MEN: BLUE (2017) #23 by Bunn and Molina. This group wanted to trigger a wave of new mutations with the Mothervine Virus, a compound extracted from an alternate reality Wolverine's son. When she realized the Mothervine mutants would be under Sinister's control, Frost rejected this plan. 

After Frost turned against the cabal, Xorn unleashed the black hole in his head and seemingly killed Bastion. Although Bastion may be gone, anti-mutant forces like Orchis and the Omega Sentinel have kept his dark legacy alive by developing new Nimrod technology and pushing mutants to the edge of extinction.

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ASTONISHING X-MEN (2004) #1 artwork by John Cassaday and Laura Martin


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