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This is an overview article which contains background information and cross-game comparisons. For game-specific information and stats, see the articles linked on the right.
Gameplay articles
FalloutMariposa super mutant
Fallout 2Mariposa super mutant
Fallout 3Super mutant
Super mutant brute
Super mutant master
Super mutant overlord Gametitle-FO3 BS
Super mutant behemoth
Fallout: New VegasSuper mutant
Super mutant brute
Super mutant master
Nightkin master
Mariposa super mutant
Nightkin jailer
Nightkin sniper
Fallout 4Institute super mutant
Super mutant suicider
Super mutant skirmisher
Super mutant brute
Super mutant enforcer
Super mutant butcher
Super mutant master
Super mutant overlord
Super mutant primus
Super mutant warlord
Super mutant behemoth
Fallout 76Huntersville super mutant
Super mutant brute
Super mutant suicider
Super mutant skirmisher
Super mutant fighter
Super mutant enforcer
Super mutant butcher
Super mutant master
Super mutant overlord
Super mutant primus
Super mutant warlord
Super mutant behemoth
Super mutant pillager Gametitle-FO76 NW
Super mutant demolisher Gametitle-FO76 NW
Super mutant gladiator Gametitle-FO76 NW
Super mutant champion Gametitle-FO76 NW
Prime behemoth Gametitle-FO76 NW
Fallout: BoSMariposa super mutant
Fallout TacticsSuper mutant
Van BurenMariposa super mutant
Project V13Super mutant
Gametitle-FO1Gametitle-FO2Gametitle-FO3Gametitle-FO3 BSGametitle-FNVGametitle-FO4
Gametitle-FO1Gametitle-FO2Gametitle-FO3Gametitle-FO3 BSGametitle-FNVGametitle-FO4Gametitle-FOTGametitle-FOBOSGametitle-FO3 TPGametitle-FO3 BSGametitle-FNV DMGametitle-FO76Gametitle-FBGametitle-VBGametitle-FOBOS2PV13Gametitle-TARGametitle-FOXGametitle-D20

Super mutants are mutated humans, products of infection by the Forced Evolutionary Virus (FEV). They are much taller, bulkier, and more muscular than pure strain humans, have predominantly green, gray, or yellowish skin, are immune to disease and radiation, and are gifted with superhuman strength and endurance. Although they are completely sterile, the rapid regeneration of their cells caused by FEV makes them virtually biologically immortal (but not immune to death from injury).

There are four different known sources of super mutants in the post-War world - Mariposa Military Base in New California (on the West Coast), Vault 87 in the Capital Wasteland (on the East Coast), the FEV labs of the Institute in the Commonwealth (East Coast), and Huntersville in Appalachia (East Coast). The four populations have separate histories and origins and are yet to interact with each other. While originally the term was only used to refer to the Mariposa stock, the Brotherhood of Steel carried the term with them and applied it to those from Vault 87 upon encountering them.


Super mutants are a uniform group of mutants created by the exposure of humans to the Forced Evolution Virus. Originally created by West Tek as the Pan-Immunity Virion, FEV research was spun off on governmental orders when it was realized that PVP was an extremely potent mutagen. Changes to DNA are expressed phenotypically due to recursive growth patterns coded in the FEV. The goal was the creation of super soldiers capable of fighting in any conditions with minimal preparation. The primary research effort was set up at Mariposa Military Base in California, with a competing research initiative spun-off at Vault 87 under Dr Wayne Merrick. The Commonwealth Institute of Technology also had access to FEV samples, allowing it to set up its own research efforts after the Great War.[1]

Super mutant transformation requires prolonged immersion in the virus: in Mariposa this has been achieved by a 24-hour exposure to FEV-II in the vats, achieving a severe overdose of the virus.[2][3] In Vault 87, infection took place in sealed chambers, where an aerosolized virus was introduced. The exposure was relatively brief, compared to the Mariposa procedure.[4][5] The Institute practiced prolonged immersion in FEV, in contained tubes.[6]

A noted feature of FEV is that it partially relies upon the DNA of the individual coming in contact with it. Coupled with portions of its own recursive code, effects of exposure can be unpredictable,[7] particularly when non-humans are exposed to the virus, or multiple organisms are placed into the same vat (vide centaurs).[8]


Although there is variation between super mutant types depending on the FEV strain used and the contents of the recursive growth patterns used, there are many similarities. The average super mutant created by the Mariposa strain is 3.2 meters (10.5 feet) tall and weighs in excess of 350 kilograms (800 pounds). Muscle accounts for over 75% of body mass, while bone and tissue are 10% each. Fat mass is exceedingly low, accounting for between 3-5% of body mass.[3] The Vault 87 super mutants stand approximately over 2.44 m (8 feet) tall and the Institute super mutants are approximately 2.13 m (7 feet) tall. The increased muscle and body mass will lead to a change in posture: Mariposa super mutants have a characteristic, hunched stance, Vault 87 mutants have a distinct forward neck posture, while Appalachian and Institute mutants have a drooping posture. The skin becomes much thicker and resistant to trauma, including cuts, bruises and damage from fire, acid or even gunfire. Muscle and bone structure are enhanced well beyond the human norm.[3] Despite this resistance to trauma, completely destroyed tissues cannot be regrown, and will result in permanent scarring or organ loss.[9]

Super mutant cells undergo cellular division at a greatly increased rate. Mitosis occurs at a rate of 15% quicker than that found in pure strain humans. A super mutant's cellular structure is said to be highly similar to normal humans. Super mutant DNA strands are nearly flawless, with all of the recessive genes that produce many of the most common ailments like diabetes, cancer, and cardiovascular disease eradicated from the genome. Those recessive genes which are commonly found in humans have been manipulated in such a way by the infection of the FEV as to bring about the best possible combination of genetic traits. A super mutant's RNA structure was also altered by the virus to produce more rapid transcription, resulting in the enhanced regenerative capacities of the mutated form.[3]

The mutation produced by the FEV, in this case, has some severe side effects. Chief among them is sterility. As the gametes of the reproductive system consist of 'half-cells' comprising only 23 of the normal 46 chromosomes, they are perceived as 'damaged' cells by the FEV's integrated genetic sequences, which "repairs" them by restoring the missing chromosomes, which renders the mutants sterile since their gametes lose the ability to recombine with other sex cells in sexual reproduction. Other side effects of this form of FEV infection include an alteration of the pigment cells of the epidermis. While the super mutants originating from Mariposa are sterile, they do not lose their sexual organs, but they do lose their secondary sexual characteristics, such as breasts; Similarly, East Coast mutants are said to lose most sexual characteristics[10] Another side effect is the overdevelopment or "sagging" of the upper lip on the mutants, causing discomfort when talking and/or chewing, which led to them creating very simple leather straps as "braces" to make it easier to perform the aforementioned tasks.

While they will not normally die due to the normal effects of aging, super mutants are prone to senility, leading to tendencies to engage in near-psychotic, aggressive attacks against humans and other creatures.


West Coast mutantsEdit

Super mutants in the Mojave Wasteland are remnants of the Master's Army and the Enclave's experiments at Mariposa Military Base.— Loading screen

The Mariposa super mutants are a variety of super mutants common on the West Coast and in the Midwest that originated from the Mariposa Military Base in California. While some of them can be rather stupid, in general, they are more intelligent and civilized than their distant Huntersville, Institute, and Vault 87 cousins found in Appalachia, the Commonwealth, and the Capital Wasteland respectively. Their skin is also darker than that of their east-coast counterparts. The Mariposa strain is unique in that the mutants created by it do not continue to grow in size as they age, unlike the East Coast strains.


Marcus, sheriff of Broken Hills

Super mutants were first created on the West Coast by Richard Grey, also known as "The Master", who led the first human survivor expedition to Mariposa Military Base in 2102. When the expedition was attacked by the base's automated security robots, he was dipped in a vat filled with mature FEV in solution and managed to crawl out. The FEV was initially meant to be injected into humans, but Grey soon found out that direct physical contact with its nutritional medium worked just as well. He began to mutate in horrible ways, turning into a fleshy, tentacled blob of sentient matter.

The mutated form of Grey developed psychic powers, which were enhanced by consuming living minds to expand his own psionic strength. Slowly, as other wanderers from the Wasteland made it into the Mariposa Base themselves, Grey started performing his own experiments with the FEV. Grey — who now called himself "The Master" — lamented the needless destruction of human society caused by the Great War. In his warped state, he decided that he would have to force humanity to evolve beyond its innately destructive tendencies. If everyone could be as perfect as his evolutionarily advanced super mutants, the Master reasoned, there would be no more conflict in the world. Those who would not evolve would be forcibly sterilized and allowed to live out their lives in peace, though without the ability to pass on their imperfections to the next generation.[11] Around the year 2155, the Master began seeking out uncontaminated, pure strain humans with which to create new mutants and build the super mutant army he required to carry his plans to fruition.

FNVSuper mutant

A Mariposa super mutant in Fallout: New Vegas

In 2162, the Vault Dweller destroyed the Master's mutant army by causing an explosion in the FEV vats at Mariposa, which collapsed the entire base, subsequently destroying the Master. Without the leadership of their creator and his lieutenant, the mutants divided into at least three factions. Some decided to leave California and find a place for themselves somewhere in the east, while a second faction wanted to continue the Master's work and dominate New California once again. A third faction remained in New California and tried to make peace with the wasteland's humans, and worked together with them to rebuild the world after the Great War. Broken Hills is an example of a settlement where humans and super mutants have learned to live together in peace.

The faction of super mutants that traveled eastwards eventually settled in the Midwest, forming what was known as Gammorin's Army, and many of them eventually ended up joining the Brotherhood of Steel.[citation needed]

In 2236, the Enclave, the remnant of the pre-War American federal government, discovered the remnants of the Mariposa Base. Soon, Enclave assault squads combed the desert for slaves they could use to excavate the military base and get to the FEV vats. In 2237, having obtained the necessary data and samples to recreate the FEV, the Enclave abandoned the site after more mutations occurred among Enclave personnel exposed to the FEV remnants in the facility, causing the second generation of Mariposa super mutants to arise. The Enclave left a single squad behind to wipe out the super mutants, but the mutants, using armaments they had cached in the base during the excavation, reduced the squad to ashes after suffering heavy casualties. The remaining 1st and 2nd generation super mutant slaves were sealed inside the base by Enclave sappers, who collapsed the entrance to the ruined facility. Inside, the mutants formed a new community.

At some point before 2281, super mutants from both generations established a community on Black Mountain near New Vegas, initially led by the former sheriff of Broken Hills, Marcus. However, a nightkin named Tabitha arrived and conflict ensued, resulting in a portion of the group leaving to found a settlement called Jacobstown on Mount Charleston. The mutants who remained at Black Mountain, renamed the State of Utobitha, were openly hostile to humans.

East Coast mutantsEdit


There are three types of super mutants found in the East Coast. All strains differ from the Mariposa strain in that the mutants they produce are less intelligent, but continue to gain muscle and body mass as they age, eventually becoming behemoths.

Shortly before the Great War, West Tek released FEV into the drinking water of the town of Huntersville, West Virginia as part of an experiment, creating the first super mutants in Appalachia. By 2102, this strain of super mutant had spread across the region. They are accompanied by similarly mutated hounds and floater.

By 2277, the super mutants had also appeared on the East Coast of the United States. These super mutants were created in the Evolutionary Experimentation Program, the experiment which had been assigned by Vault-Tec and the pre-War American government to Vault 87 as part of the clandestine Vault experimentation program. The heavily modified strain of FEV which created these mutants resulted in a new strain of super mutants which, in addition to becoming sterile, grow much larger and stronger as they age. They are different from their New California counterparts as they are green-yellow in skin color and less intelligent. Every super mutant's facial expression is permanently set in a sneer. However, unlike their counterparts, they are even less like pure strain humans, and after the transformation, no clues on how they looked in their former lives can be found. They take human prisoners across the Capital Wasteland to transform them into more super mutants by injecting them with the FEV still found in Vault 87. Just as on the West Coast, the byproduct of the Vault 87-based creations are the hideous chimeric mutants called centaurs, who act as watch/attack dogs for their super mutant masters.

By 2287, a unique large group of super mutants are found in the Commonwealth, as experiments of the Institute. This group of mutants also has similarities to the ones from the Capital Wasteland and the West Coast. Unlike the Vault 87 and Mariposa mutants, the ones found in the Commonwealth are not accompanied by centaurs but instead, travel with mutant hounds.

During the exploration of Vault 87, information from a computer terminal reveals more about the process of mutation that super mutants go through, at least when it comes to the specific modified strain of FEV found in the super mutants of the Capital Wasteland. As a human mutates, its muscular and skeletal systems develop rapidly, while their mental faculties diminish. Most secondary sexual characteristics are eliminated, transforming the subject into an asexual state.

Despite their general lack of intelligence (even when compared to the least intelligent of the West Coast super mutants), they are somehow able to organize themselves into a coordinated army (as evidenced by their numerous raids and the attempt to reinforce their positions at the Capitol which led to the attack on Galaxy News Radio), procure large amounts of advanced weapons, ammunition, and equipment, and even maintain the biomedical infrastructure necessary to infect humans with the FEV and increase the numbers of super mutants in the region. In the urban ruins of Washington, the super mutants are looking for more sources of FEV and more humans to expand their own numbers as they seek to take over the entire Capital Wasteland.

The Commonwealth mutants seem to show more intelligence (with the exception of behemoths) than their Capital Wasteland counterparts, as they speak in more complex sentences, as well as shouting out slightly more intelligent battle cries and taunts. They seem to use better tactics, especially with higher ranking mutants. However, even though they are more intelligent than Vault 87 counterparts, they are still less intelligent and more uncivilized when in comparison to those on the West Coast.

Notable super mutantsEdit


  • The name of the super mutants is spelled differently at different points. Despite the fact that "super mutant" is the most characteristic and the most widely used, other variations exist including super mutants, super-mutant, supermutant and mutants.
  • While Marcus, the super mutant in Fallout 2, claims that "it only takes a few years to get the juices flowing again" (in regards to sterility), Chris Avellone, who wrote the dialogue, said that it was just a joke.
  • Some mutants in Mariposa in Fallout 2 are called "super duper mutants."
  • Fawkes prefers to use the term "Meta-Humans" when speaking about the super mutants, especially when referring to himself. However, he is the only character who refers to super mutants in this way.
  • Fawkes also reveals that the "super-mutation" causes extreme pain and that it's the key factor that turns the Vault 87 strain of super mutants feral and inhumane. Fawkes states that he barely withstood it himself.
  • The only super mutant to be cured of the FEV is Brian Virgil from Fallout 4.
  • In Fallout Shelter, dwellers venturing the wasteland may note that super mutants are now asexual, but were from either sex before transformation.[12]
FOBoSLogoThe following is based on Fallout: Brotherhood of Steel and has not been confirmed by canon sources.
FOBoSLogoEnd of information based on Fallout: Brotherhood of Steel.


Super mutants appear in all Fallout games to date.


Fallout and Fallout 2
Fallout 3
Fallout: New Vegas
Fallout 4
Fallout 76
Fallout Tactics
Fallout: Brotherhood of Steel
Van Buren
Fallout d20
Project V13



  1. See Forced Evolutionary Virus for references.
  2. The Vault Dweller: "{142}{}{What is the current status of the patients?}"
    Vats Control Computer: "{143}{}{Current status on patients as follows: FEV batch #23872-A consists of four male units and two female units. All individuals suffering from FEV exposure. Vital signs are within normal parameters. FEV process on all subjects is approxiamtely 50% complete. Expect full FEV transformation within 12 hours.}"
  3. 3.0 3.1 3.2 3.3 Vree's autopsy report
  4. The Lone Wanderer: "A friendly Super Mutant. Well, now I've seen everything."
    Fawkes: "Ugh. Must you use that vulgar term? Yes, I was born in the F.E.V. Chambers but a Super Mutant I certainly am not. I prefer the term Meta Human. Suits me better don't you think?"
    (Fawkes' dialogue)
  5. Vault 87 exposure chambers.
  6. FEV lab
  7. Cite error: Invalid <ref> tag; no text was provided for refs named ZAX.MSG
  8. Fallout Bible 0: "3. Are the radscorpions a product of the FEV virus? When you talk to the doctor, Razlo, in Shady Sands, he tells you that they were once American Emperor Scorpions but that he has no idea how they mutated because radiation alone couldn't have done it. For that matter, what about all of the other creatures of the wasteland? Which ones have been mutated by FEV and which ones haven't? Maybe in the bestiary each creature could have a stat that shows it's level of FEV infection."
    • The radscorpions are a result of a combination of radiation and the FEV virus, and Razlo in Shady Sands is correct - they were originally Emperor Scorpions that have grown... big.
    • FEV-Infected Critters in the wasteland include almost all the ones you've seen in F1 and F2:
      Most species of rats.
      Gecko lizards.
      Various varieties of plants, including the Venus Flytrap.
      Rumor has it some dogs were affected, but no one's seen any, so for now that's just rumor. Of course, the centaurs are a mash of human, dog, and various other parts... but hey, who knows how that mutation came about. Grey was probably messing around in one of his labs.
    • Creatures not mutated by FEV probably did not survive the aftermath of the Great War, with the possible exception of cockroaches... and perhaps normal ants, though there are FEV-infected versions of these species.
    • No one knows where those bird noises in Vault City came from.
    • I'll try to include a chart of FEV-infected creatures in future additions as well as other critters that you may not have seen in F1 and F2. Most likely a great majority of insects were affected (they tend to breed much faster, and their mutations tend to become evident pretty quickly as the generations advance), possibly beetles, some spiders, cockroaches, and other creatures."
  9. The cybernetic implants, branding scars, and the amputated tongue of Lieutenant, Dog and God, and Mean Sonofabitch respectfully are examples of permanent tissue damage.
  10. Vault 87 terminal entries; Entry 87-34224
  12. Possible wasteland monologue: "Explorer's journal. New entry. Super Mutants are asexual. Before transformation, some were women."
  13. Fallout: Brotherhood of Steel Manual p.34: "Mutants
    While Ghouls are the product of evolutionary transformation, mutants are man-made. Big, massively muscled, and savage, they are far stronger than any human and are able to handle heavy weapons with ease. Originally created by some “brilliant” scientists, who thought it would be a neat idea to dip ordinary folks into a toxic goo swimming with a “Forced Evolutionary Virus”, the mutant menace has since caused the wasteland more than its fair share of problems. The process of creating mutants also seems to have some kind of random factor - as some mutants are highly intelligent, while others are as dumb as a post."
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