Fanfic / My Hero Academia: Unchained Predator

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And he shall be joined by another. One whose rage, strength and ferocity are equal his own. Together, they will rain destruction, death and devastation upon all they deem evil...^note Art by lukehonor

My Hero Academia: Unchained Predator is a triple crossover fanfic between My Hero Academia/Doom (2016)/Darksiders written by reeleffendeel on FanFiction.Net.

Following the conclusion of DOOM 2016, the Doom Slayer is warped into a world of Heroes and Villains. But when the Demons invade the alternate world, the Slayer's crusade against Hell will lead him to different worlds and revelations alongside newfound allies... and their guardian Angels.

The author also has this fic on Archive of Our Own now. You can read it here.

My Hero Academia: Unchained Predator provides examples of:

• Acquired Poison Immunity: Doom Slayer is unaffected by Midnight's sleeping gas since he has long been adapted to breathing Hell's toxic and deadly atmosphere.
• Adaptational Badass:
  • The Doom Slayer himself gets an ample helping of this. While already incredibly badass in the canon Doom (2016) universe, here he destroys a literal black hole with his bare hands and takes on multiple top-level Heroes with nary a scratch; only All Might actually damages his armor, yet he ultimately falls to the Doom Slayer as well.
  • The League of Villains gets this treatment, with the Steel Sabers arc revealing that they have more members than in canon, with one of them (Volcano) being responsible for decimating Esuha City. It has been revealed that they also got access to the last known cache of VX Gas on the planet.
  • VEGA receives this too. In canon, he was mainly a Mission Control Non-Action Guy for most of the story, whereas he actively helps the Slayer in many different ways in this story, from hacking the mainframe of I-Island, cutting off all communication from both the heroes and the villains to taking control of several drones to kill several Sabers soldiers. One scene, in particular, has VEGA fighting side-by-side with Doomguy against the remaining Sabers while controlling a large construction mech. When the Hologram grenades are upgraded, VEGA is able to access them to fight alongside the Doom Slayer.
• Adaptational Early Appearance:
  • The story takes place during the last parts of the Final Exams Arc. Nine, along with his sidekicks, make a cameo in Chapter 7 before they actually appear in Chapter 9. Their true debut didn't happen until My Hero Academia: Heroes: Rising, which takes place after the Meta Liberation Army Arc, not to mention the film after the first one (which is where the Steel Sabers arc takes place).
  • Mirko appears in Chapter 2, while Hawks, Crust, and Ryukyu show up in Chapter 8, well before their actual debut in the Pro Hero Arc.
  • Fatgum appears in Chapter 3, while in canon he appeared during the Shie Hassaikai Arc.
  • Lady Nagant appears at the end of chapter 12 when she wouldn't appear until the Villain Hunt Arc.
  • Sir Nighteye shows up as he's heading back to Japan following the I-Island disaster instead of in the internships.
  • Ippan shows up far earlier than her canonical appearance, being rescued from three rapists by the Slayer.
  • Ms. Joke and several of her students show up before the Hero Licensing Exam Arc, as the Slayer has to rescue them from a villain gang that captured them.
  • Inasa and Camie show up two chapters after Ms. Joke and four of their classmates instead of the Hero Licensing Exam Arc.
• Adaptational Heroism: The Hero Public Safety Commission is far more moral in this story compared to their mainline counterpart. In canon, they were revealed to be totally corrupt and their previous director used Lady Nagant as an assassin to kill everyone suspected of villainy or interfered with their objectives. Even after being replaced by his successor, the HPSC was still only somewhat less corrupt. In here? While the author stated that they are not 100% clean by any means, they haven't committed any of the atrocities they oversaw in canon and want to genuinely help everyone in Japan.
• Adaptational Superpower Change: Yoroi Musha's Quirk was unknown in the canon story. Here, he has the ability to create katana blades from his fingers, likely in accordance with his Samurai motif.
• Ain't Too Proud to Beg:
  • A Saber called Marley begs the Slayer to spare him, promising that he'll turn over a new leaf. This not only failed, it enraged the Slayer even more, as all he could think of were Marley's victims who begged him for the same thing before he killed them anyway.
  • Some of the thugs beg for their lives or try to strike a deal with the Slayer as the Slayer hunts them down in the Warpath Arc. The Slayer doesn't give mercy to any of them, other than a boy forced down the wrong path.
• All Myths Are True: Confirmed by several of the Christian angels who frequently mention gods and beings from other pantheons.
• Alternate Universe Fic: Aside in a more literal sense as the Hero Academia world is stated to be an alternate universe to that of the Slayer's home universe, it becomes evident that both universes differ somewhat from their source material:
  • Nine in this universe leads the Steel Sabers, a deadly mercenary group that is known for having killed over 246 heroes and is hired by All for One to help Wolfram to take over I-Island, and his name is based on the age where he killed his first Hero, not his number of quirks.
  • Lady Nagant became a Vigilante and never went to prison, but given the Hero Public Safety Commission isn’t anywhere near as corrupt as they are in canon, it makes one wonder what made Lady Nagant go rogue compared to her original counterpart.
  • Oboro Shirakumo isn't dead, so he doesn't get turned into Kurogiri, who in here is just another subservient Nomu.
  • Mirko in this universe is shown to have a darker past than in canon, as unlike in canon when she was simply the punk vigilante Tiger Bunny who snuck into several illegal fighting tournaments and got kicked out of several schools before becoming a top Pro Hero, here her old vigilante persona is revealed to be much more violent as she used brutality and a shotgun against villains and criminals alike before being rehabilitated into the bunny hero Mirko. But it seems remnants of her past have begun to leak out from the Doom Slayer’s presence, only to be fully unleashed in Chapter 41.
• Ambiguous Situation: It's unknown if Samuel Hayden forcibly sent the Slayer to the MHA universe on purpose because he knew something about it beforehand that would distract & occupy the Slayer the longest or if he just inputted a random set of coordinates to the tether and hoped the dimension he winds up in doesn't have the technological advancement and esoteric level to get him back so Hayden could continue using argent energy for humanity's "benefit" as long as possible.
• A Mind Is a Terrible Thing to Read: Ragdoll gets a lot more than she bargained for when she mind-scans the Doom Slayer.
• An Arm and a Leg:
  • During their confrontation at the mall, the Slayer rips Shigaraki's arm out of its socket and begins beating the villain with it. Initially, the arm can't be recovered due to police scrutiny, but All For One's forces manage to steal it from lockup while the nation is distracted by the Slayer's battle against the Steel Sabers.
  • After killing Chainsaw, he rips off several of his chainsaw arms to get himself a new weapon, the Sawtanas.
  • In Chapter 18, the Slayer rips off Swordkill's arms and uses the severed arm blades to decapitate him.
• Anti-Hero: The Doom Slayer takes up this role easily. He may brutalize villains but doesn't dare attack innocents. If anything he becomes even more savage to any villain who dare hurts an innocent person in his sights. And the few run-ins with pro heroes were provoked by them and even then, he only aimed to incapacitate them. His Start of Darkness appears to have been getting reassigned to Mars in his early days after assaulting a superior officer who ordered him to open fire on civilians.
• Armor of Invincibility: Thanks to the Slayer's armor being forged in Hell by a rogue Demon known as "The Wretch" and then enhanced by the UAC’s technology, bullets shatter like glass against him and explosives barely make him stagger. It even stands up to Endeavor's flames and Volcano's magma. That being said, All Might has proven capable of denting it, albeit only with his strongest attack.
• Ask a Stupid Question...: Several instances of this, though the Slayer gives the perfect nonverbal responses.
  • When Hawks asks the Slayer if it was justified to paint I-Island red with the blood of the Steel Sabers, the Slayer looks at him in disbelief as VEGA reveals all the atrocities Nine and his forces committed, forcing Hawks to concede that the Slayer made his point, though he still thinks it was too far.
  • When All Might asks the same question, the Slayer's response is to glare at him before stomping a dead Saber's head into paste to tell All Might that yes, what he did was entirely justified.
• Asshole Victim:
  • You can't feel bad for Shigaraki after the Doom Slayer rips his arm off and starts beating him with it. Unfortunately, Dabi saves him before the Slayer can finish him off.
  • The Steel Sabers, under the command of Nine and his lieutenants, kill heroes for a living and for sport, so it's hard to feel bad for them once the Slayer makes them pay for every hero they killed. Even a few of the Heroes such as Mirko and Ryukyu quietly muse that the Slayer did the world a favor by wiping them out, with their allies in the League of Villains not sad to see them go either.
  • Wolfram dies in Chapter 19, and he deserved it after becoming a crazed psycho (even more so than before) with the Quirk Amplification Headset.
  • Arbalest, Skullbash, and all the other villains in the Warpath arc are killed with their men after the Slayer and Vega catch wind of their operations, but given how they were happy to murder people and do a lot of horrible things in All for One's name, they had their deaths coming for them.
  • The Bogans get a long-overdue taste of their own medicine once Miruko and the Slayer start tearing through them like wet paper.
• Ate His Gun: The Doom Slayer kills Nine this way by shoving the barrel of his own Taurus Raging Judge revolver into his mouth.
• Atop a Mountain of Corpses:
  • When the Slayer butchers 1,000 Sabers in a blind rage, once he snaps out of it and looks about, he finds himself standing on top of their mutilated corpses surrounded by an ankle-deep lake of blood, much to the terror of the next group of Sabers.
  • During Ragdoll's mind incursion of the Slayer, one of the visions she sees is him standing on top of a literal mountain of disemboweled, dismembered and mutilated demons. She tries to replicate the scene on a hospital wall with a scalpel.
• Attack Drone: VEGA hacks the I-Island drones to brutally dispatch several Steel Saber mercs. When All Might looks at one of the destroyed drones, he's left lost as to why the drones went berserk and started butchering the mercs if they were designed to subdue intruders.
• Ax-Crazy: Very much subverted with the Doom Slayer. He is adept at carrying out wholesale massacres without any care for property damage or the consequences of his actions, thus being justifiably perceived as a walking death zone by the heroes. However, the man is capable of discerning hostages and civilians from enemy combatants, and unlike the heroes, has no qualms using deadly force if it means the hostages live. Nezu outright admits that the Slayer is an enigma to him, for the man is brutal to his enemies, but not to civilians. All-Might also figures out that the Slayer is holding back when fighting him and the other heroes, realizing that despite his relentless brutality, he won't hurt any innocent people.
• Back-to-Back Badasses: VEGA hacks into a mech and starts helping the Slayer by attacking the Sabers with it. In the Warpath Arc, the Hologram grenades are upgraded to allow VEGA to fight alongside the Slayer, much to the Slayer's excitement.
  VEGA: Your hologram projectors will now create a hard-light duplicate of yourself. The construct is armed with your Heavy Assault Rifle, which is, like itself, a hard-light object and uses ammunition made of the same material. However, it cannot use your other weapons as well as their Mods. By linking myself to it, I can control the copy to assist you in combat. The duplicate will function indefinitely and will detonate in a disorienting explosion similar to that of a flashbang grenade on my command.
• Bad Boss:
  • Nine, who was not in a very good mood, kills a Steel Sabers mercenary for not considering using the stairs when the EMP from the Slayer blowing up their nuclear submarine shuts down the elevators.
  • Wolfram abandons his lieutenants to the Doom Slayer as he attempts to make his escape from I-Island.
    Curator: Didn't you just say to your dogs that we were going to wait for them?
    Wolfram: Screw 'em.
• Bearer of Bad News: VEGA tells the Slayer that the MHA world essentially views that teleportation is impossible, essentially telling the Slayer that they were both trapped in the MHA world. This gets subverted when VEGA reveals that the Fabricator can build the materials needed to build a teleporter, though it would take 70 years.
• Benevolent A.I.: Same as in the games, VEGA (in his suit) serves as the Doom Slayer's main ally, gathering information and guiding him on his course. Mind, that's just benevolent to the Slayer and their "allies". To their enemies, on the other hand…
• Berserk Button:
  • The Slayer is not pleased when the League of Villains tries to harm Miruko due to her reminding him of both his deceased wife Emily and his dead rabbit Daisy. Wolfram is stupid enough to smash it after he impales Miruko with rebar on I-Island, leading to a very pissed off Slayer beating him to a literal pulp.
  • When destroying the gang of Fatal Ficus and killing a snake that he was using to feed rabbits to, the Slayer merely wishes he could bring Fatal Ficus back to life so he could kill him repeatedly.
• Beyond the Impossible: The Slayer in chapter 21 manages to catch and crush a BLACK HOLE sent from Thirteen. In the same chapter, All Might manages to actually dent parts of the Praetor Suit, which earns him more respect from Taggart for being able to harm him to begin with.
• BFG: That's the Doom Slayer's taste in guns; even his smallest gun, a standard UAC EMG (Energy-Matter-Gel) pistol, described as a laser gun in the setting of MHA, can cause a lot of damage to their targets. His other guns fire shotgun shells, .50-caliber rounds, or plasma, not including what the weapon mods reconfigure the ammunition to. Also, having a minigun (the Chaingun) and a railgun (the Gauss Cannon) does help matters. And that's not counting that he hasn't pulled out THE BFG-9000 yet, because of its dependency on Argent Energy, restricting its use to 2 more shots (as he already used one of the 3 shots on Olivia Pierce/The Spider Mastermind), plus the argent tendrils don't distinguish between friend or foe.
• Big Bad Wannabe: The author actually puts All for One, of all people, here. In canon, he was the Big Bad and Greater-Scope Villain of the story, but in the fic, the author states soon he will be writing checks he won't be able to cash, which all but means that once the demons come, he'll be nothing more but an afterthought. It’s very doubtful AFO would be trying to make deal with the Demons or the Maykrs, let alone be successful due to his arrogance. It’s also quite likely that Shigaraki will end up in the same boat, if not slightly worse off, since he doesn't even have AFO's charisma on top of being a moronic Psychopathic Manchild.
• Big Damn Heroes:
  • Miruko arrives at the I-Island central tower's rooftop just in time to aid Izuku's group against the League of Villains in chapter 17.
  • The Doom Slayer makes his Dynamic Entry from the stairwell of I-Island's central tower just as Miruko's about to Hold the Line against the recovered League of Villains operatives to help Izuku's group and Melissa Shield escape.
• Blood-Splattered Innocents: Many of the hostages the Slayer rescues end up being doused in the blood of the criminals the Slayer butchers with zero hesitation.
• Blood-Splattered Warrior:
  • The Slayer is coated in the blood of his enemies after killing thousands of Sabers in Chapter 15. He is also covered in blood from slaughtering the many gangs All for One ordered to cause chaos throughout Musutafu in the Warpath Arc.
  • Miruko ends up covered in the blood of the Bogans she killed during the Mustafau General Hospital attack.
• Bloodier and Gorier: Like you won't believe. The Doom Slayer single-handedly inflicts this trope upon the My Hero Academia universe with his patented and unrelenting brutality against villains.
• Blue-and-Orange Morality: The Doom Slayer has long been desensitized to the violence he inflicts against any threat to innocents, thanks to his eternal crusade against Hell. While the Heroes recognize that Slayer has enough sense to hold back against them, the slaughter he leaves in his wake is far too much for any of the cast to stomach. His propensity for violence is simply unheard of, and the body count following the I-Island bloodbath is higher than most heroes see in their whole careers. The only person in the MHA-verse who even remotely has a clue to the reasons behind Slayer's brutality is Ragdoll, and her mind snapped like a twig after trying to read his. It literally took an archangel to restore her mind from the damage using her Quirk on the Doom Slayer wrought on her sanity.
• Booby Trap: The Slayer takes out a large portion of Fatal Ficus' gang by hiding grenades inside a wine bucket underneath a block of ice, with the wine bottle having a string tied to one of the grenade pins before sending it up by the bellhop elevator.
• The Bogan: The Bloody Bogan gang sent by All For One to attack Musutafu General Hospital while the Doom Slayer was distracted killing all of the other gangs AFO had hired to cause mass destruction, is even more brutal than the Steel Sabers, blowing up the children's ward for kicks, among other atrocities. Imagine a gang of Jan Valentine clones with an Australian accent, and you'd have a very good idea of what the Bogans are like.
• Boom, Headshot!: How Nine meets his end in chapter 16.
• Break the Cutie:
  • Ochako was so traumatized by seeing the Doom Slayer rip Shigaraki's arm off that she developed PTSD. Things get worse for the Zero Gravity user when she and the other captives from the Central Tower of I-Island have to walk through the Rivers of Blood that the Slayer left behind when he killed the Steel Sabers.
  • Ragdoll is left screaming in terror after she looks into the Slayer's mind and sees his war against Hell. The poor girl was about to tear into her head until Midnight knocked her out and by her next appearance, she's a traumatized wreck.
• Break Them by Talking: Curator gives one to David about how his fanaticism towards All Might led to I-Island being taken over by the most dangerous mercenaries in the world and putting everyone in danger, including his own daughter. When he's done, Melissa can't even look at him.
• Bring My Brown Pants:
  • A police officer soils himself when the Slayer neutralizes his car by ripping the engine out.
  • Papa Prism promptly soils himself when he sees the Slayer kill his last henchman and is armed with a Gatling Gun. He desperately tries to bargain with his life, but the Slayer promptly kills him before he could continue his plea.
• Bullet Catch: A tank gunner fires a shell at the Slayer in a desperate attempt to kill him, but he just catches it with one hand.
• Bunnies for Cuteness: A rabbit the Slayer rescues in Fatal Ficus' base and then hands to Camie and Inasa. Camie admits the rabbit is utterly cute.
• Calling Your Attacks: The Doom Slayer mentally lampshades the ridiculousness of this trope after he has to listen to the heroes constantly yell out the names of their attacks during their brawl on I-Island and swiftly gets tired of that habit.
• Couldn't Find a Pen:
  • The Slayer paints his symbol and the words RIP AND TEAR on a wall in I-Island with Chimera's blood at the end of Chapter 16.
  • Ragdoll carves out the Slayer's symbol and him standing Atop a Mountain of Corpses with a scalpel along with the message The Only Thing They Fear Is Him.
• Cape Busters: The Steel Sabers were mainly trained to fight against Heroes by learning their Quirks and weaknesses for years. Knowing that they managed to kill 246 Heroes before I-Island, it was safe to say that they were pretty effective before the Slayer crossed their path.
• Cool vs. Awesome: The Doom Slayer vs. All Might in Chapter 21.
• Cornered Rattlesnake: After having to endure immeasurable amounts of trauma surviving against the Bloody Bogans, the Pro Heroes holed up in Mustafau General Hospital finally abandon Thou Shalt Not Kill and slaughter the marauding terrorists after Mirko and the Doom Slayer reinforce them.
• Creepy Good: The Doom Slayer qualifies with his brutality and unshakeable morals.
• Crippling Overspecialization: The Steel Sabers specialize in fighting heroes such as All Might. Against someone like the Doom Slayer, they are at a massive disadvantage. As the Slayer notes, the Sabers fought heroes, not a warrior with a 'kill first, ask questions never' policy.
• Crisis of Faith: Flynn Taggart used to be a devout Catholic back on his homeworld before his war against hell. His encounter with the Maykrs has severely damaged his faith and can only wonder if the angels of the MHA universe are any different.
• Cruel and Unusual Death: This story is a crossover between Doom and My Hero Academia, and people will die in brutal ways, though some deaths stand out the most.
  • In Chapter 16, Nine and his crew die in the most brutal ways imaginable; considering how vile they were in the original movie AND this story, they deserve every bit of it.
    • Mummy gets a leg blown off before he gets his throat sliced open before being ripped in half.
    • Slice's scalp is ripped off along with her face and eyelids before she gets her head crushed into paste.
    • Chimera is completely shredded with the Slayer's chaingun.
    • And lastly, Nine meets his end after the Slayer shoves his Taurus revolver down his throat before blowing his skull off.
  • In Chapter 18, the Slayer delivers this to Wolfram's goons.
    • Specs has his brain ripped out before being torn in half vertically.
    • Swordkill has his arms ripped off before being decapitated with them.
    • Daigo is disembowled with Swordkill's severed arms, before being hurled into one of Nobu's attacks, decapitating him.
    • And lastly, Nobu has his arm shattered and the bone shoved through his mouth like a makeshift shiv.
  • In Chapter 19, Wolfram gets killed when the now royally pissed off Slayer tears him out of his junk golem, explodes all of his organs with a single stomp of his foot and headbutts him into oblivion. The villain's head got crushed so hard that the story describes it as a dropped pie.
  • In the Warpath Arc, Fatal Ficus has his hand ripped off, the pointed ends of his fingers shoved through his groin, and then impaled through the throat and out his mouth.
• Curb-Stomp Battle: The Slayer hands these out left and right to not only villains but also any heroes unlucky enough to try and slow him down. In fact, the story's Establishing Series Moment is him all but eviscerating Shigaraki in Chapter 5.
  • Chapter 8 has him facing Eraserhead, Slidin' Go, Mr. Brave, Loud Cloud, Mirko, Hawks, Fatgum, Crust, Gran Torino, Ryukyu, and Endeavor. He isn't even slowed down for a millisecond as he bulldozes through them. In fact, the author notes that this is him trying not to kill anyone.
  • The Steel Sabers on I-Island get to be victims of an extremely one-sided fight against him, throwing everything they had at him to no effect. Two Sabers manage to operate construction mech suits to try and kill the Slayer… only for the suits to be dismantled so easily that he was actually disappointed at how easy they were to beat.
    Well, that was pathetically easy. The Hell Guards were way tougher than these cheap knockoffs.
  • Swordkill, Specs, Nobu, and Daigo are quickly and brutally killed by the Slayer.
  • Endeavor tries to attack the Slayer after the Steel Sabers are exterminated only to get the shit beaten out of him with laughable ease. The Slayer even let the jackass think he has a chance of winning just to screw with him. When the rest of the Japanese Heroes and the formerly captured Heroes try their luck against the Slayer, it goes much worse than last time, ending with every one of them defeated.
  • Every villain gang that the Slayer tracks down are easily wiped out by the Slayer before they can even begin their terror campaign on All for One's orders.
• Curb-Stomp Cushion:
  • At first, the Saber leaders manage to disorient the Slayer and even destroy his Great Communicator. But once they lose the element of surprise to monologue, he goes right back to work.
  • Thirteen's Desperation Attack. While the Slayer inevitably stops it - it actually makes him feel caution (a first for any MHA ability), and explicitly takes all his strength to do so (another first).
  • While the fight between All Might and the Slayer still ends with the latter's victory, the former ends up denting the Praetor Suit and giving the Slayer some damage under it, which earns him The Doom Slayer's respect.
• Darker and Edgier: What happens when you put the demon-killing machine known as the Doom Slayer in the world of My Hero Academia? You get this story, and it hasn’t even gotten to when the demons of DOOM begin to invade this alternate Earth…
• Dark and Troubled Past:
  • Mirko, in this alternate timeline, was, at one point, Tiger Bunny, a hyper-violent vigilante who hunted criminals with a shotgun and wore a tiger-patterned Luchadore mask. When met with scenes of extreme violence, she finds herself torn between absolute horror at the reminder of who she once was and bloodlust.
  • The Slayer's past. Having been reassigned to a space outpost after assaulting his superior officer, only to fight The Legions of Hell, lose his family to said Legions of Hell, went absolutely insane ripping and tearing demons apart until he was kicked to another world, where he found a home in the form of the Night Sentinels, only to be betrayed by the Maykrs and Deag Priests working with The Legions of Hell, leading to a Roaring Rampage of Revenge that leaves all of Hell utterly terrified of him until The Legions of Hell manage to seal him away in a sarcophagus, only to be released and after killing the Spider Mastermind, is kicked to the MHA world by Samuel Hayden. The Slayer wonders if fate truly hates him that much for this to happen to him.
• Deconstructed Trope: Chapter 41 ends up lampshading and deconstructing the idea of Thou Shalt Not Kill and Honor Before Reason: Mera stated that due to the emphasis placed on "no killing", it meant that no hero was prepared for the moment when they had to use lethal force, blaming Nezu for preventing it for the sake of being protecting their integrity. Considering how much carnage the Bloody Bogans unleashed before the heroes got around to using lethal force, he has a point.
• Decomposite Character: Oboro Shirakumo and Kurogiri are two separate people.
• Deconstruction Crossover: Doomguy's ultraviolent methods in how he handles villains and criminals deeply horrified and traumatized everyone, both children and adults. Even though the Slayer's victims are villains and criminals, and he never harms innocents, the Pro Heroes and law enforcers, however see him as a very dangerous serial killer who must be stopped.
• Defiant to the End: Boiling Point, one of AFO's allies, gets disemboweled by the Slayer who also slayed her entire Villain group. While holding on to her guts from dripping out, she angrily curses the Slayer by ranting that AFO will came after him. The Slayer then shuts her up by blowing up the upper half of her body with his Super Shotgun.
• Desperately Looking for a Purpose in Life: The Slayer feels lost for a while, not knowing what to do with himself besides killing criminals. When VEGA learns of All For One and tells him about him, the Slayer decides his purpose is to hunt him down and terminate him until VEGA can build a way back to his universe.
• Didn't See That Coming: The Slayer and VEGA are this to the MHA world. When Hawks and an injured Miruko find out VEGA is an intelligent, sentient AI, Hawks says this word for word while Miruko is convinced this is a drug-induced hallucination.
• Didn't Think This Through:
  • Wolfram doesn't tell the Steel Sabers about the Doom Slayer, believing he would never show up, forgetting to notify them that they maybe should pick a different fallback point outside of Musutafu, where the Slayer was last spotted. Sure enough, they accidentally stumble upon his hideout, he finds out their plans, and derails the entire I-Island plan.
  • Bakugou decides to fight the Slayer at the end of Chapter 21, forgetting that A, this man just killed 10,000 people in one night. B, he beat up 48 heroes, including All Might, and only sustained superficial dents on his armor. And C, his quirk would be as useful as wet toilet paper. Predictably, Bakugou gets captured, and when he tries to launch another attack, he doesn't notice the leaking fuel tank, but All Might and Miruko do, nearly getting them and himself killed had the Slayer not tossed them aside.
    • This gets taken further in Chapter 41, where his parents find out Bakugou had escaped to go to the hospital. The same hospital the Bogans are attacking. Whatever happens afterward, it will end up backfiring on him entirely.
  • The Doom Slayer goes on a rampage across Musutafu, killing every gang that was planning to kill off as many heroes, hero students and law enforcement personnel, completely forgetting that they will be diverted there to clean up the aftermath. This allows All for One to get the Bogans to Musutafu General Hospital along with the High-Ends to kill all the incapacitated heroes. The Slayer curses himself for this short-sightedness, even though the alternate was letting the gangs proceed with their plans with numerous hero and law enforcement casualties left in their wake.
  • When Strife suggests going down there to meet with the Doom Slayer, Death, War and Fury shoot it down by pointing out that they're half angel, half demon (and the Slayer hates demons) and as much as they are strong, neither one of them want to fight a man who they know will likely wipe the floor with them.
• Dies Differently in Adaptation: Nine dies by the Slayer's hand instead of getting killed by Shigaraki.
• "Die Hard" on an X: The Slayer's intervention (read "Villain bloodbath") during the I-Island siege turned this universe's version of the events of the Two Heroes movie into a hell of an aversion.
• Do Not Taunt Cthulhu: Even though no one knows the Slayer is a demigod with an undying hatred for The Legions of Hell, the last member of Don Puru's gang should've known better than to taunt and mock the Slayer every time he missed his shot.
• Double Take:
  • Volcano ends up doing this when he sees the Slayer tank one of his lava blasts as a Human Shield, and come out of it with no damage. Even his companions and Curator are in disbelief at that.
  • Camie and Inasa look between the chefs and the Slayer when the former group explained to the two hero students that the Slayer is their hero for ensuring Fatal Ficus and his gang can't come back to harm them or their families.
• Dirty Coward: Slidin' Go backs out from fighting the Doom Slayer by lying to the Heroes that he would stay behind to watch and protect the civilians and Ragdoll. In reality, not only is he aware that going against the Slayer would be outright suicide due to what happened to the Steel Sabers, he wants to relay information about the Slayer's activities to the Meta Liberation Army.
• The Dreaded: The Slayer was already this to the demons, but he earns a frightful reputation through his patented blend of ultraviolence. His first encounter with Shigaraki and Dabi leaves the normally smug villains scared shitless. And in the aftermath of slaughtering the Steel Sabers, thousands of fully trained hero-killing mercenaries that were holding everyone on I-Island hostage, leaves most Heroes and Villains in Japan outright fearful of him. Even All Might's blood ran cold while having to watch the I-Island bloodbath, noting that he's never seen such a level of savagery in his long career as a hero. This even extends to The Ascendant Realm and the Prime Council, who initially thought the Slayer was a myth and when he's confirmed to be real, both are at a loss as to what to do with him.
• Dynamic Entry: The Doom Slayer arrives on the rooftop where the VX Gas warhead is located by using an elevator car to slingshot himself up the shaft the car is in during chapter 17, punching through the roof in the process.
• Enemy Rising Behind: The Doom Slayer comes right behind three Steel Sabers mercenaries making a televised demand to the public. They remain ignorant of the Slayer's presence (as Nine cannot warn them since VEGA shut down their communications) until he pulls out his chainsaw in full view of everyone watching.
• Equipment Upgrade: In chapter 31, after the Slayer finishes building a bus-sized fabricator and a large supercomputer, VEGA upgrades his UAC grenades, hologram projectors, and gun mods, builds two Sawtanas (chain-katanas), replicates ammo (even Plasma Cells without Argent Energy), and turns a motorcycle into a combat trike motorcycle.
• Even Evil Has Standards: When looking through Gentle Criminal's perspective, he showcases disgust and contempt at both the Steel Sabers and the League of Villains, viewing their atrocities as nothing short of sadism and cruelty while he felt sympathy for the heroes the Sabers killed in the past.
• Everyone Calls Him "Barkeep": Because no one not of mythical origin has any idea who the Slayer is, let alone his actual name, everyone merely calls him "The Vigilante".
• Everyone Has Standards:
  • Everyone is flat-out horrified by the sheer violence the Slayer dishes out upon his targets, even if they had it coming.
  • Despite being extremely dangerous, the Slayer hates sending hero students to fight Curator and the Volcano Thieves, because apart from Mirio, the rest haven't even made it past their first semester of Heroics. VEGA understands this, and explains that it's either that, or they let them detonate the VX gas and abduct Melissa for enslavement, which the Slayer concedes.
  • The HPSC official picking up the remains of the Slayer's Great Communicator is uneased and alarmed at the thought of a security company manufacturing chainsaws as security weapons. But considering they don’t know anything about the reason WHY this is the case…
  • In Chapter 26, an especially pushy reporter from America barges into the hospital Izuku and the others are at and starts questioning him even though Izuku is absolutely not in the mood and severely traumatized from what happened on I-Island, never mind the fact that the bulk of 1A were either also traumatized or disgusted with that reporter. Aizawa arrives and threatens to give the reporter a colonoscopy with their camera if they don't get themselves out of the hospital as soon as possible.
  • When told that VEGA cannot produce ammo for the BFG, the Slayer concedes it, knowing that Argent Energy is a bad thing given what happened to Argenta and the alternate Mars, and internally admits he'd refuse to let the world know of it for their own safety.
  • Both the Slayer and VEGA believe that rapists do not deserve to live after finding three trying to rape Josei.
  • As much as both Shoto and Natsuo hate Endeavor, they don't want to see him dead.
  • Twice, Magne, and Mr. Compress are horrified at the death and destruction at Musutafu General Hospital caused by the Bloody Bogans, even more so when they witness their so-called "comrades" within the League of Villains callously brushing off the deaths of the civilians caught in the crossfire.
• Evil Wears Black: The Steel Sabers wear pitch-black uniforms and are amoral mercenaries who have killed many Heroes over their years of operation.
• Eye Scream: Plenty.
  • The Slayer gouges out Chainsaw's eyes in Chapter 16, so that he cannot use his Medusa Rays attack. In the same chapter, he also gouges out one of Chimera's eyes with his Heavy Assault Rifle.
  • One of the flares Miruko fires at Wolfram strikes into his eye and burns it out.
  • Plenty of thugs, mercs and villains alike get their eyes gouged out at the hands of the Slayer.
  • Narrowly averted in Chapter 26, when Aizawa, Hawks, Nezu, Recovery Girl and several orderlies manage to restrain and sedate a completely insane Ragdoll before she could gouge out one of Miurko's eyes because Hawks and Aizawa didn't inform her that Ragdoll had read the Slayer's mind and went insane as a result.
  • Miruko gouges out a Bogan's eyes before taking out his Desert Eagle and putting nine bullets into his chest.
• Face Death with Despair: In Nine's final moments of Chapter 16, he is filled with the very same helplessness and terror he inflicted upon his victims throughout his time leading the Steel Sabers as everything he did on I-Island to defeat the Slayer was All for Nothing. All he can do is stare into the eyes of the Hellwalker before the trigger is pulled.
  • The Slayer makes it his personal note to ensure All for One feels the same helplessness and terror he inflicted upon innocents throughout this bastard's wretched life.
• Face–Heel Turn: Rokuro Nomura, formerly known as the Semtex Hero C4, now works for All For One after he betrayed the heroes.
• Facepalm of Doom: The Doom Slayer non-fatally grabs Midnight's face and pulls her inside Cementoss' prison before knocking her out.
• Failed a Spot Check: Bakugou launches another attack on the Slayer despite being captured, failing to notice the leaking fuel truck, or the fact the fuel was surrounding where he was about to attack. Miruko and All Might justifiably panic because Bakugou nearly got them killed had the Slayer not tossed them away from the gas.
• Fate Worse than Death: David Shield is left to stew in the aftermath of his mistakes, as his fanaticism towards All Might led to I-Island being taken over by the most dangerous mercenaries in the world and putting everyone in danger, including his own daughter, and indirectly also decreasing the amount of time All Might can be a hero after the climactic fight against the Slayer. The Slayer even felt that keeping David alive to let him suffer the consequences of his shortsightedness and stupidity was a far more appropriate punishment for him (granted, Samuel Abraham betrayed and altered David's original plan).
• Feed It a Bomb: The Slayer feeds one of the thugs in the Warpath Arc one of his new grenades and tosses her into a bunch of fuel tanks.
• Forced to Watch: Everyone during the Steel Sabers Arc were forced to watch as the Slayer made mincemeat of the namesake mercenaries - in the most literal sense imaginable. By the time the Slayer heads to the ballroom, the hostages and Wolfram's gunmen begin panicking because they saw him turn 10,000 people into literal mincemeat without so much as a scratch on his armor. La Brava's explanation to Gentle at the end of Chapter 25 shows just how badly both the Sabers and the heroes were outmatched.
  La Brava: I kept thinking that the only way the Sabers could’ve attacked I-Island was if they hacked the security systems. So I managed to hack the island’s main server and access the cameras to find out what was going on. (shuddering breath) They’re… they’re all dead.
  Gentle Criminal: The hostages…?
  La Brava: No. The Sabers… he killed them all…
  Gentle Criminal: B-b-by who-?
  La Brava: (becoming more and more hysterical) The other heroes couldn’t even stop him… I don’t think even All Might stood a chance against him!
• First Injury Reaction: Played with in that the Slayer wasn’t physically hurt, but when All Might's punches prove strong enough to dent his armor, he gets excited at the prospect of his first real fight in eons, which All Might delivers despite ultimately losing in the end.
• The Friend Nobody Likes: Despite being affiliated with the League of Villains, Wolfram and his men were not on friendly terms with the other LOV members such as Dabi, C4, Muscular, Magne, Mr. Compress, and Mustard. After learning about the deaths of Wolfram and his underlings at the hands of the Slayer, the LOV members express their contempt towards their so-called comrades.
• Gaining the Will to Kill: When Miruko snaps in Chapter 41, she brutally begins to dispatch the Bogans inside the hospital before they could kill Recovery Girl. The other Pro Heroes trapped in the hospital follow suit in chapter 43 after Edgeshot points out that fighting to subdue the Bloody Bogans is no longer viable or possible, though Lady Nagant is far from impressed since it took them years to realize this brutal but necessary truth.
• Genre Shift: Whereas the canon manga was a shonen with its fair share of violent moments, the author has made noticeable strides to make Unchained Predator more akin to a seinen work, with a strong focus on the adult cast and cranking the violence far past anything in canon MHA. On top of Class 1-A being utterly traumatized by the Doom Slayer's rampages and having their naively idealistic mindsets crack heavily as a result of the violence they witness, the story also dives into the seedier aspects of its world with the shortcomings of a society so obsessed with superheroes.
• Go Mad from the Revelation: Ragdoll attempts to mind-scan the Slayer to pinpoint his location on I-Island. Needless to say, looking into the Slayer's Dark and Troubled Past has not been conducive to her sanity. After the events of I-Island, Ragdoll began drawing pictures of the Slayer, his Mark, and the demons along with inscribing "the only thing they fear is him" over and over while recovering in the hospital. The only reason her madness wasn't permanent was because the Archangel of Dreams, Jeremiel, later relieved Ragdoll of the visions plaguing her with the Creator's backing.
  Ragdoll: IT CAME FROM HELL! IT CAME FROM HEEEEEEEEEELLLLLLL!
• God's Hands Are Tied: The Ascended Realm and the Prime Council have willingly chosen to distance themselves from human affairs some time ago, with The Creator only allowing a "one miracle per mortal" policy, as demonstrated by Jeremiel erasing the demonic visions from Ragdoll's mind. This frustrates Uriel, who desires nothing more than All for One being eradicated.
• Good Counterpart: The Ascendant Realm are this to the Maykrs, being a genuinely benevolent faction that cares for the mortals in sharp contrast to the Maykrs who willingly sacrificed countless worlds for power.
• Good Is Not Soft: VEGA may be a benevolent AI who's a Nice Guy to his allies, but make no mistake, he is just as ruthless as the Slayer, having no problem getting his virtual hands dirty and joining the fray in combat.
• Gorn: Every single encounter between the Doom Slayer and any of the villains results in this, usually taken to the extreme. In the later parts of the Steel Sabers arc, the streets of I-Island are literally choked with blood, and plenty of scenes show him tearing out spines and crushing skulls in terrifyingly brutal fashions.
• Green-Eyed Monster: Bakugo is left furious over Yagi/All Might having chosen Izuku as his successor. Although Yagi explains his reasons for why he picked Izuku, Bakugo angrily retorts that Yagi chose Izuku for being better than him.
• Grew Beyond Their Programming: The Slayer notices that since arriving in the MHA Universe, VEGA has begun to show more signs of initiative and drive, almost like the Artificial Intelligence is beginning to evolve and become more like a real person than an actual machine.
• Grievous Harm with a Body:
  • Doom Slayer tears off Shigaraki's right arm with his bare hands as part of his brutal beatdown against the smug supervillain in the Kiyashi Ward shopping mall.
  • During his attack on the Steel Sabers, the Slayer picks up a Saber soldier by the leg and uses him as a club.
  • He rips off Swordkill's arms and uses said arms to decapitate him, then disembowels Daigo with one of the severed arms before popping Nobu's arm and shoving it straight through his skull like a makeshift shiv.
  • In the Warpath Arc, he uses various severed body parts and even other criminals as weapons.
• Groin Attack:
  • A non-lethal variant with Pankration, as the Slayer does this while trying to knock him and the other heroes out.
  • The Slayer castrates a thug with his rifle, using some ricochet capabilities to avoid hitting Josei, and then when she's away from them, viciously kill the last two would be rapists.
  • After ripping off Fatal Ficus' hand, he proceeds to stab the sharpened incisions into his groin before killing him.
• Harmful to Minors: In less than a week of the Doom Slayer's arrival, the students of 1-A become severely traumatized at the various villain massacres that he unleashes and they personally witness, especially the one on I-Island. This extends to 4 of Ms. Joke's students, who either got to see or hear the Slayer getting to work on a gang that captured them and Ms. Joke.
• Hero with Bad Publicity: While far from a traditional hero, the Slayer ends up on the shitlist of both sides of the law by the end of the I-Island fiasco. The League of Villains wants him dead for nearly killing Shigaraki, and the Heroes intend to capture him for butchering the Steel Sabers, unintentionally destroying Ragdoll's sanity, and beating down the Heroes sent to apprehend him. Not that he cares about their opinions of him. The only reason the Heroes aren't focusing solely on him is because of the chaos caused by so many Pros being out of action after I-Island.
• Heroic BSoD: When Bakugo discovers All Might in his emaciated state and learns how said hero is losing his powers, he becomes far more withdrawn and taciturn.
• Heroic Mime: Apart from flashback sequences, the Slayer never speaks, utters a word, or grunts in pain - literally no sound. VEGA does the talking, whether it's to Izuku and his friends, Miruko and Hawks, or the HPSC President.
• Hidden in Plain Sight: When Hawks is searching for the Slayer, he's left wondering how the hell the Slayer found so many villain gangs and organizations hiding in plain sight and slaughtered them all before they could enact their plans.
• Hoist Hero over Head: Heroic example. The Doom Slayer hoists Mummy and breaks him in half over his knee. To add insult to injury, he then throws Mummy's upper half into a pile of debris that spears into his face.
• Honor Before Reason:
  • The heroes in MHA have moral codes, so it's expected that a lot of them aren't going to accept the Slayer's actions, much to his chagrin. The Slayer inverts this hard due to his eternal war against the forces of Hell desensitizing him to all forms of violence, and the moral codes of the Heroes confuses him more than anything. In short, he would rather take out any threat to innocent life immediately than leave it to the authorities and pro-heroes. This is demonstrated when he nearly kills Shigaraki and Dabi if not for Kurogiri's Warp Gate teleporting them at the last minute.
    • While Shigaraki, even while the story begins at the end of MHA's second season, has done nothing but cause pain for Class 1-A and is the de facto leader of the League of Villains, both Izuku and Tenya stand up to the Slayer during the Mall incident to demand him not to execute the nearly dead Shigaraki and hand him over to the police.
  • During Chapter 13, Nejire and Tamaki try to stop him from killing the Steel Sabers until they decide that making sure the hostages are safe is more important.
• Hope Spot: During the Slayer's incursion into the Insecticides' base, the gang leader hears that the Slayer isn't going to kill him and he's relieved and thanking God… until VEGA tells him that they weren't talking to him, but rather the 14 year old boy in his ranks.
• Hostage Situation: Wolfram's last remaining mercenary, who is cornered by the Doom Slayer, desperately points his gun at a detained All Might and orders the Slayer to stay back in a futile bid to not end up like the rest of his comrades or the Steel Sabers. However, the Slayer quickly punts a chair into the gunman's face before he could pull the trigger, causing him to drop his weapon and allowing the Slayer to gruesomely finish him off.
• Hostage Video: The Steel Sabers make a ransom demand with the intent to keep the heroes and JSDF from interfering until they finished emptying out the vaults, only for it to go sideways when the Slayer casually walks up behind the three giving the ransom demand, pulls out a chainsaw, and saws the trio in half in a grisly Public Execution.
• How We Got Here: The first part of Chapter 18 let readers know what the Slayer done from the end of Chapter 16 to his Dynamic Entry: he came from the elevator shaft in the hall with hostages to save their lives from death before Bakugo and Kirishima came there, then he killed Specs, Nobu, Daigo and Swordkill, then he saved Mirio's life by catching a slab of sharpened metal inches away from his face and finally, he destroyed a blockage of rubble on the stairwell to come onto the roof.
• Human Shield: Due to the Armor of Invincibility that is his Praetor Suit, the Slayer has no qualms using himself as a human shield to protect others, such as when he shields Izuku and his friends from Volcano's magma strike, or protects Rumi from a score of deadly rebar spear strikes.
  • When he uses a random thug as a human shield in the Warpath Arc, he mentally admits it was a spur of the moment.
• Immoral Journalist: Tony Pope is an obnoxious American reporter who barges into a hospital room in an attempt to force an interview with Izuku after the Slayer turned I-Island into a blood-drenched slaughterhouse, completely uncaring of the fact that A. he's a minor, B. he's completely and utterly traumatized, and C. the reporter was essentially trying to be the first to report on what happened at I-Island. Aizawa has to threaten to shove Tony's camera up his ass so he could leave.
  • Worse, he decides to add his two cents by insinuating on a live broadcast that Pro Heroes are essentially super‑powered time bombs, after the heroes decide that they need to kill the Bogans to stop them. That kind of statement will obviously cause people to lose faith in Hero Society at large, which is the last thing they need after already suffering through a terrorist attack and choosing deadly force over capture. And of course, considering what’s implied to be coming much later, this only makes everything worse. And it doesn't help the villains may decide to up their game to combat the fact the heroes are no longer willing to hold back...
• Immune to Fate: Usiel and the seers from the other pantheons ultimately discover the Slayer's fate is completely unwritten and seems to have the ability to alter the fate of those around him. The author stated this was inspired by Goblin Slayer's apparent ability of "not letting anyone roll the dice".
• Impeded Communication: VEGA disables all forms of communication between the HPSC and the heroes and JSDF forces near I-Island during the Steel Sabers Arc until after the Slayer gets back into the sewers to his hideout.
• Implied Death Threat: In Chapter 12, once the cameras of I-Island come back on, the Slayer rips off a dead Saber's head and holds it up to the camera to crush it to give one simple message to Nine: he has come to kill him. By Chapter 16, the Slayer makes good on that threat, killing Nine and his lieutenants.
• Improvised Weapon: During the earlier parts of the I-Island assault, to be stealthier, the Slayer makes use of some saw blades, rebar, a sledgehammer, and a fire axe, all to deadly effect. When he goes loud, he uses a destroyed APC turret as a makeshift war hammer, a double tanker full of gasoline as a makeshift napalm bomb, an active APC turret he yanked off, a tank turret he also yanked off to use as a club, and a glass plate to decapitate one of Wolfram's gunmen.
  • During his culling of the villain gangs in Musutafu, he hurls poker chips at members of Don Puru's gang like shurikens, uses an engine and chain as a makeshift flail, as well as a gas tank and a blowtorch for a makeshift flamethrower on a villain gang that Ms. Joke and four of her students stumble upon.
• Inheritance Murder: When reviewing Curator's background, the Slayer finds that Curator had killed his entire family in a staged traffic accident to get the inheritance meant for his younger, much more successful brother. When the authorities found out through investigations, they managed to detain Curator (though not before he killed several cops and a hero), and were transferring him to Tartarus, only for All for One to break him out. The Slayer makes a mental note to kill Curator slowly.
• Innocence Lost: After witnessing the Steel Sabers and The League Of Villains take over I-Island and seeing them getting horribly slaughtered by the Doom Slayer later on, all of Class 1A’s students are completely traumatized (even Bakugo and Todoroki), with some beginning to develop PTSD.
• Insane Equals Violent: After Ragdoll went mad reading the Slayer's mind, none of the heroes or hospital staff are aware of how bad it is until they find out she attacked a nurse and stole a scalpel. When they find her, she's overpowering Miruko while trying to gouge one of her eyes out with the scalpel, forcing them to put her into full-body restraints because she's now a threat to everyone around her - until Jeremiah removes those memories.
• Internal Reveal: All Might reveals the One for All-All for One feud to Ochako, Melissa, Bakugou, Miruko and Hawks after his fight with the Slayer.
  • When VEGA explains to the Slayer the reason behind upgrading his gear and the motorcycle, the Slayer is all in for killing All for One and every villain that gets in his path.
  • Hawks ends up telling the Slayer how he knew of the existence of One for All and who else knew (not the identities of the UA students, though the Slayer knows Izuku is the ninth wielder), even though the Slayer already knew about it thanks to VEGA.
• "It" Is Dehumanizing: Near the end of the Steel Sabers arc, Mummy states that most of the Steel Sabers are dead because of the Slayer, or as he put it, that thing. In Chapter 18, Curator also refers the Slayer as that thing when he saw him tank a lava strike and take no damage from it.
• It's Personal:
  • Both Shigaraki and Endeavor don't take their defeats at the Doom Slayer's hands gracefully, with the former later throwing a COLOSSAL tantrum over how the Slayer nearly killed him.
    • In Chapter 20, Endeavor (being his usual hot-headed self) throws caution to the wind and tries to surprise attack the Slayer... It doesn't go well for Enji.
    • Chapter 24 reveals that Shigaraki is still very pissed at Flynn for tearing off his arm and beating him with it. Re-watching what he did to him on TV is more than enough to get him angry.
      Tomura: Hate you. Hate you. Hate you. Hateyouhateyouhateyouhateyouhateyouhateyouhateyouhateyohateyou...I HATE YOU!
    • In chapter 41 Shigaraki destroys a chair after he saw on TV that the Slayer arrived to Musutafu General Hospital.
  • The Doom Slayer takes quite some offense at how the Steel Sabers not only kill heroes, but also desecrate their corpses.
  • When VEGA confirms that Chainsaw is a bio-organic weapon, no similar to the UAC's Revenant Project, the Slayer views the League of Villains as a credible threat that must be destroyed.
  • In chapter 19, seeing Miruko being (thankfully non-fatally) impaled throughout her body by Wolfram reminds the Slayer, or rather Flynn, of the moment he lost his family and pet rabbit Daisy, causing him to go BALLISTIC on Wolfram.
• It Can Think: Curator jokingly implies Volcano can think when he reveals he has the blueprints for the QAH, much to the villain's anger. Granted, Curator was still pissed at Volcano for using his lava Quirk near the VX Gas canister they brought to the island in Chapter 18.
• Jawbreaker: The last gunman who thought using All Might as a bargaining chip to not be dismembered like all the others finds the Slayer casually ripping his jaw off - along with the entire frontal portion of his body, causing his organs to spill on the floor.
• Judge, Jury, and Executioner: The Slayer delivers summary justice against the villains he faces. Unlike the Heroes and their Thou Shall Not Kill policy, the Slayer kills all who he believes pose a threat to innocent lives or Hero society at large.
• Just One Man: Everyone's reactions to the Doom Slayer’s one-sided massacre of the Steel Sabers.
  Narration: Nine never felt this angry before in his whole life. How could this have happened?! He trained his soldiers to combat Heroes, study their Quirks, exploit their weaknesses and show them that they weren't invulnerable. How was this man capable of decimating them this damn quickly! It was maddening!
• Killing in Self-Defense: During the Bloody Bogan's attack on the Musutafu Hospital, Vlad King ends up killing some Bogans in self-defense as a result of his Quirk Awakening (due to the trauma and horrors Sekijiro had endured) in which he unintentionally exsanguinated their blood, rendering them into bloodless, near-skeletal bodies. Sekijiro was left horrified by what he had done.
• Killed Mid-Sentence: A lot of crooks killed by the Slayer's hand end up doing this, often while begging for their lives at the hands of a man who offers mercy to none of them.
• Know When to Fold 'Em:
  • After the Doom Slayer beats nearly all the Pro Heroes (46 of them, to be exact) and leaves only Rock Lock and Aizawa standing, Rock Lock realizes that fighting the Slayer is utterly hopeless and tries to get Aizawa to run away. The Slayer knocks out Rock Lock before he can run.
    Aizawa: Ken, what the hell are you-?!
    Rock Lock: We have to get out of here!
    Aizawa: What?! We can’t just leave her-!
    Rock Lock: WE CAN’T FIGHT THIS GUY! JUST FUCKING RUN-
  • Many villains in the Warpath Arc try to run, surrender or beg and plead for mercy from the Doom Slayer, only for it to fail.
• Kung-Fu Sonic Boom: During their battle, the shockwaves created from All Might and the Slayer trading blows are so strong they crack pavement, shatter glass, flip over cars, and even topple buildings, to say nothing of their final clash, which kicks up an F-5 tornado around them.
• Laser-Guided Amnesia: Jeremiah removes all of Ragdoll's memories from the moment she read the Slayer's mind, making it to where she never remembers going utterly insane, carved the Slayer's symbol and the message "The Only Thing They Fear Is Him", or tried to gouge Miruko's eye out with a scalpel. Of course, this leads to Ragdoll wondering why Miruko is scared of her when they meet up.
• Last Disrespects: After killing Papa Prism, the Slayer decides to add one final insult to his corpse by dumping a bowl of Skittles onto him.
• The Law of Diminishing Defensive Effort: Both Doom Slayer and Miruko tend to ignore attacks. The Slayer can afford to since his armor is practically indestructible, but Miruko ignores her injuries out of pride and bravado. VEGA, Hawks, Recovery Girl, and others constantly scold her and tell her to dodge already, and the Slayer internally admits that if he decided to talk, he'd most likely ask her to do the same.
• Locked Out of the Loop:
  • Wolfram leaves the knowledge of the Slayer out of the existence to Nine and his lieutenants under the belief that the Slayer would never show up. This proves to be a fatal mistake, and Volcano wastes no time explaining to Wolfram that this mess is on him regardless of if Sir Kills-A-Lot shows up or not.
  • When Ragdoll has a complete psychotic break reading the Doom Slayer's mind, Hawks and Aizawa knew the extent of it, but Miruko, Izuku, Ochako, Mirio, Melissa, All Might, Sayaka and Mera do not. This nearly comes back to bite Miruko hard when Ragdoll nearly gouges her eye out with a scalpel in Chapter 26, with All Might, Sayaka and Mera finding out in Chapter 27.
  • When she is cured of her insanity, no one bothers to tell her about her 48 hour psychotic break that nearly culminated in her gouging Miruko's eye out, which leaves her confused as to why Miruko is scared of her.
• Madness Mantra:
  • A very pissed Shigaraki falls into an "I hate you!" rant at a stilled frame of the Doom Slayer's face.
  • Ragdoll etches one into a hospital supply closet wall saying “The Only Thing They Fear Is Him.”
• Mass "Oh, Crap!":
  • The Doom Slayer's utter eradication of the Steel Sabers is this for Japan's Hero community and Villains who know what went down (namely La Brava, who had a front-row seat after she hacked into I-Island's camera system). For the Heroes, their fear is more based on Slayer being Just One Man who quite literally painted I-Island with mercenary blood on live TV and had the strength to not only combat the Heroes sent to apprehend him but even fight All Might to a standstill.
  • The heroes, police, emergency services and hero students alongside any villain that could instantly recognize the Slayer all have this reaction when the Slayer decides to start cleaning Musutafu of villain gangs associated with All for One in the most brutal manners possible.
• Mauve Shirt: Several of AFO's gangs are led by notorious and colorful criminals, all of whom get a decent description of who they are and how they rose to power in the criminal underworld. The are all brutally killed by the Slayer's hand shortly after being introduced to the story.
• Meaningful Name: Chapter 16 is titled "End of the Sabers". Guess what happens to the rest of them?
• Modern Stasis: Despite the MHA world being in the 22nd century, technology has more or less stagnated in early to mid-21st century levels thanks to the appearance of Quirks. This plays further into the Slayer's story as there is no way for him to return to his home universe or seemingly any technology to break his Praetor Suit's armor.
• The Mole: Slidin' Go is a secret member of the Meta Liberation Army. He was tasked by the MLA to observe the Doom Slayer's actions on I-Island.
• Mood Whiplash: Hawks chases after the Slayer when he wakes up, expecting some sort of fight - only to see that he's providing medical aid to Miruko, confusing the man as he had just seen the Slayer smash Wolfram's head into paste.
• Mook Horror Show:
  • The Steel Sabers going up against the Slayer. Nothing the mercenaries throw at him can even scratch the Praetor Suit, combined with them being torn into quite literal ribbons by the vengeful Slayer.
  • The various Villain gangs that answer to All for One are exterminated to the last man during the Warpath arc, with their Quirks and weaponry being of no use against the rampaging Slayer.
  • Miruko dishes this out to the Bogans in Chapter 41 as she has now gained the will to kill, with the other Pro Heroes following suit in chapter 43 after Edgeshot points out that the only way everyone's going to survive the attack is by killing the Bloody Bogans.
• Moral Myopia: The villains think nothing of committing crimes and inflicting horrific atrocities against innocent people, yet they have the gall to be outraged/gobsmacked/terrified when the Slayer starts decimating them with extreme prejudice.
• Morton's Fork: Implied; the Warpath arc has the Doom Slayer go around Musutafu slaughtering many villain gangs that are part of AFO's plan to stretch the police and heroes thin across the city to attack the hospital. Still, because of the mess the Slayer leaves behind for the police to take care of and the occasional hero he knocks out that gets in his way (likely planned by AFO from the very beginning), law enforcement gets stretched thin anyway. Bottom line, the Slayer fell right into AFO's trick, but if he hadn't get involved, the plan would've gone the same, just with more law enforcement, hero, and civilian casualties.
• Mugging the Monster: A gang tries to mug the Doom Slayer, whom they see is a "wannabe hero". Moments later, a gangster missing his arm is running for his life before the Slayer smashes his face into a fire hydrant, to the horror of two heroes seeing this.
• Mythology Gag: The Slayer's name and backstory come from the novelization of the first game, where his name was Flynn Taggart and he was reassigned to Mars as punishment for assaulting a superior officer in response to that officer ordering him to shoot civilians. He openly mentions that the last non-zombified or corrupted human he fought was that officer shortly after seeing a robbery.
• Named by the Adaptation:
  • In canon the HPSC President was unnamed; here her name is Sayaka Grant, after her Japanese and American voice actresses.
  • In Doom canon, Doomguy's name has always been different between adaptations, here his name is Corporal Flynn Taggart, which was first used in the novelization of the first two games. And with the namesake in the Revelations DLC for Doom: The Dark Ages, his name really is Flynn Taggart.
  • One of Wolfram's lackeys, the hacker who managed to hack into the island's security in My Hero Academia: Two Heroes, is named Specs.
• Never Hurt an Innocent: The Slayer is a One-Man Army Berserker who doesn't hesitate to kill, butcher, and maim demons, villains, and anyone who endangers innocent lives, but when facing off against pro heroes who either try to stop him from reaching I-Island or departing after he eradicates nearly every last villain involved, he holds back and only knocks them out because he knows most of them are good people just doing their job.
• Nice Job Breaking It, Hero!:
  • Endeavor deciding to fly off and attack the Doom Slayer, despite the fact he had just killed around 10,000 people in one night ends with him destroying the I-Island vault and getting his ass handed to him, while also leading to the rest of the heroes getting their asses kicked and All Might being down to an hour a day.
  • The Doomslayer inadvertently gives AFO the perfect opportunity to unleash his plan. In his zeal to destroy all the gangs in Japan, he ends up causing all the heroes and law enforcement to be bogged down by all the clean up, giving AFO the opening he needed to attack the hospitalized heroes via the Bloody Bogans. While there was no good choice in this situation, the other choice being to let the gangs rampage across the city, the Doomslayer still curses himself for not thinking about the consequences of his rampage.
• No-Holds-Barred Beatdown: Shigaraki’s "fight" with the Slayer is as one-sided as can be, as one is a human tank in a literal ton of powered armor who has no patience for fair fighting while the other is a skinny man in poor physical shape that lacks any combat experience. While Shigaraki can disintegrate anything he touches, that advantage is rendered null and void once the Slayer relieves him of his arm.
• No Honor Among Thieves: The League of Villains have a nasty tendency to abandon their comrades to their doom when things go wrong. Izuku, Ochako, and Shoto silently acknowledge this trope after they overhear Wolfman choosing to leave his men behind to die.
• Noodle Incident: According to Mera's internal narration, the last person who hacked an HPSC satellite was an overweight hacker living in their mother's garage.
• No One Should Survive That!: Kunoichi Glider sums up how utterly nightmarish the Slayer was when he was destroying the Steel Sabers in Chapter 21 and how the Sabers unloaded everything that should've rendered the Slayer dead thousands of times over.
  Kunoichi Glider: The Steel Sabers unloaded every bullet, explosive, and tank they had at him. Nothing can survive any of that. But he did and the man just kept coming after them. I don’t even want to think about what’ll happen if this guy walks away from all this.
• No-Sell:
  • When reviewing the footage of his "fight" with Shigaraki, the pro heroes think his ability to pull weapons out of nowhere is a storage Quirk, rather than just advanced technology. So imagine Eraser Head's shock when his Quirk does nothing to stop the Slayer from accessing his weapons in his fight with the heroes at the docks. His eyes can only cancel other Quirks, not technology or natural strength.
  • The Praetor Suit can't be damaged by literally anything the heroes or villains throw at it. Endeavor's Hellflames are useless against it, while Hawks' feather swords snap like twigs when they make contact. Volcano's nanomachines can't consume it and his lava can't melt it. Only All Might's punches have proven capable of damaging it, albeit superficially.
  • Eraserhead manages to snag the Slayer's limbs, neck, and torso with his Binding Cloth to try and subdue him… only for the bindings around the target's limbs to rip like toilet paper, while the hero is dragged like a ragdoll from the cloth still wrapped around the latter's neck and torso. This comes as no surprise, as the Slayer is bigger, stronger, and heavier than Aizawa by a ridiculous margin.
• Not So Stoic:
  • Shoto has No Social Skills and is hard to surprise. However, when he sees the Rivers of Blood caused by the Slayer getting to work, he is terrified. The story even states that it was the first time he ever showed pure terror.
  • Despite sounding unimpressed when confronting the Slayer in Chapter 18, Curator is highly unsettled by the Doom Slayer's presence, though the fact he's covered in the blood of all the Sabers and Wolfram's goons he butchered like animals may've played it a bit more.
• Ocular Gushers: When Inko comes to visit Izuku, the two burst into tears, tears that begin to pool underneath the hospital doors. Nezu and Aizawa can't help but wonder if it’s a Quirk.
• Oh, Crap!:
  • The only reaction people have when fighting the Slayer.
    • Shigaraki, when he gets his arm ripped off, is then beaten with it. Dabi has the same response when Slayer pulls out a rocket launcher on him and Shigaraki.
    • Slidin' Go grabs the Slayer in a headlock to stop him from reaching the docks, only to freak out and duck for cover when he sees the Slayer already holding a grenade with no pin. The rest of the heroes who witnessed this are left speechless.
      Mr. Brave: Did he just-?!
      Loud Cloud: Miruko wasn't kidding; this guy really is a nut.
    • Eraserhead is later left shocked and horrified when his Quirk doesn't work on the Slayer.
    • The entirety of the Steel Sabers have this reaction when the Slayer starts killing them one by one, with none of their weapons able to even scratch his armor.
    • Nine and his lieutenants reel back when they do a full assault upon the Unchained Predator, only to find that their attacks did jack shit against him.
    • Melissa, Miruko, Izuku, Shoto, and Ochako have this reaction when the Slayer makes his Dynamic Entry onto the rooftop.
    • Bakugo is frozen in fright when he runs into the Slayer right after he has butchered all of Wolfram's hired gunmen guarding the hostages in the ballroom.
    • Nobu, Swordkill, Daigo and Mirio when they see the Slayer rip out Specs' brain and tear him in half.
    • Volcano becomes alarmed when his Nanomachines quirk is unable to consume the Slayer's armor.
      Curator: What the hell are you doing, Volcano?! Absorb his armor!
      Volcano: I-I can't!
    • Curator, Volcano, Dusty Ash and Gust Boy are all shocked that Volcano's magma doesn't melt the Slayer.
    • Ragdoll is left terrified when her mind reading of the Slayer has her find out that A: he's not from their dimension and B: Hell exists. Unfortunately for her, her mind snaps as a result.
    • Wolfram nearly shits himself when experiencing the Slayer's pure rage after he critically injured Miruko. Hawks and Miruko experience this when they see the Slayer viciously end Wolfram.
    • All the heroes look in horror at the Slayer's brutal mauling of Endeavor, with the man's shallow breathing being the only thing for them to confirm that he didn't butcher him.
    • Eraserhead, Rock Lock, Pixie-Bob and 13 all panic when the Slayer not only catches the black hole 13 sent to the Slayer, but manages to crush it with his bare hands.
    • Izuku and company are horrified when it's revealed that the Slayer, who just incapacitated 48 pro heroes and fought All Might on seemingly equal footing, was holding back the entire time.
    • The Press are terrified when they see the Slayer's symbol and are told by Sayaka that they literally know next to nothing about the guy, other than him being a Technologically Advanced Foe, killed 10,000 people in one night, and beat up 48 heroes.
    • During the Warpath Arc, various civilians, hero students, heroes and villains panic when they end up running into the Doom Slayer, especially since in the latter case, the Slayer isn't taking any prisoners.
    • Master Driller pales when he runs into the Slayer shortly after the Slayer had butchered Boiling Point's entire group. Unfortunately for Master Driller, the Slayer knocks him out.
    • The Burnin' Sidekickers scream in shock or horror when they see the Slayer cleave Multikill in half with one of his Sawtanas.
    • Yo, Tatami, Shikkui, and Itejiro are terrified as they hear or see the Slayer butcher the gang that captured them.
    • When Hawks receives reports from many heroes about literal massacres of villains with heroes being knocked out, he quickly realizes that the Slayer is getting back to work.
    • When two cops try to pull over a motorcycle, they promptly panic when they realize it's the Doom Slayer driving said motorcycle, who casually proceeds to rip out their engine and drive off.
      Cop: Good luck explaining this to the Chief.
      Cop 2: Which one? The engine, or my soiled pants?
    • The chefs Fatal Ficus enslaved by threatening to kill their families scream in terror at the Slayer butchering the man threatening them.
    • Camie and Inasa pale and become afraid when they see the Slayer walk out of Fatal Ficus' base of operations, though it fades to confusion when they see a bunny in one of the Slayer's hands.
  • When it's not the Slayer giving this, it is still prevalent.
    • When Curator, the Volcano Thieves and Chainsaw show up to I-Island in Chapter 14, the Volcano Thieves are immediately disturbed at the Rivers of Blood they see when they first arrive.
    • Wolfram and his group have this reaction when they see that Curator showed up. The narration states that if Curator is here, then it meant they really fucked up.
    • All the heroes onboard the boat Ragdoll is on panic when they see Ragdoll suddenly start screaming and trying to tear her own head open, forcing Midnight to sedate her.
    • All Might and Miruko panic when Bakugou tries to launch another attack on the Slayer, completely failing to notice the leaking fuel tanker. The Slayer was quick to pick up on their panic and hurl them away along with the explosion-slinging idiot.
    • Two cops and a schoolgirl panic when they realize the stranger they ran into is actually the Fallen Hero C4. Unfortunately for them, C4 kills all three of them.
    • Gentle freaks out when he finds out La Brava hacked into the I-Island security system, and her explanation only causes more distress to her.
    • Nezu, Aizawa and Hawks have this reaction when Recovery Girl and several orderlies explain that Ragdoll is missing and had attacked a nurse. The latter two more prevalent because they knew Ragdoll was not in a sound state of mind.
    • Miruko when she finds out that Ragdoll has gone insane and is actively trying to gouge her eye out with a scalpel.
    • Shortly after they sedate her, Nezu, Recovery Girl, Aizawa, Miruko and Hawks all become uneased when they find out that Ragdoll was not only able to carve the Slayer's symbol, despite having never seen it, nor stepped foot on I-Island, but also the Slayer standing Atop a Mountain of Corpses with only one message repeated: The Only Thing They Fear Is Him.
    • Yo, Tatami, Shikkui and Itejiro panic when a villain knocks out Ms. Joke and another captures them.
    • Just about everyone is frozen with horror when the attack on Musutafu General Hospital is being broadcast on all news channels, especially with how utterly vulnerable the Pro Heroes recovering there are.
    • Bakugou's parents, when they realize their son escaped the house and is heading to the same hospital the Bogans are attacking.
    • The captured heroes Miruko frees are horrified at seeing the Number 5 Hero of Japan covered in blood after brutally killing several Bogans - even though they deserve it.
    • The Bloody Bogans and League of Villains panic once they realize that the Heroes have actually decided to use lethal force against them, with Spinner frantically trying to reassure himself that they don't have the will to kill.
• The Omniscient Council of Vagueness: The Ascendant Realm and Prime Council are this, so far the only two known members are Uriel and Usiel. The amount of knowledge they have on the Slayer is rather telling as they both are aware of the Helix Stone and his role as the destroyer of evil.
• One-Man Army: The Doom Slayer, with some technological assistance from VEGA, handily takes on the entire Steel Saber forces and wins.
• The Only One Allowed to Defeat You:
  • Dabi and Muscular are respectively pissed at the Doom Slayer for effortlessly beating up Endeavor and killing Wolfram and his men rather than him.
  • During the Bloody Bogans' attack on Musutafu General Hospital, Dabi secretly leaves the League's base so he can kill Endeavor himself rather than let the Bogans get to him first.
• OOC Is Serious Business:
  • When Miruko tells Hawks "Good luck in trying to stop [the Slayer]", he looks at her in concern, as he knows Miruko would never show hesitation in fighting someone. Granted, at the time Hawks doesn't know that Miruko saw the Slayer literally tank a lava blast and emerge unscathed.
  • Recovery Girl notes that Ragdoll isn't religious. So, when she starts rambling about gods, angels, demons, and devils among humanity, Armageddon and worlds on fire, along with the extremely dangerous and violent behavior she displayed alongside her carvings, it unnerves her.
  • When Papa Prism tells his last henchman he's calling the cops, the man is stunned at that notion, as he would never call the cops (unless they're the Dirty Cops under his payroll) to his establishment. Granted, it's heavily implied he was planning to cut a deal with law enforcement in exchange for being put in a prison that is as far from the Doom Slayer as possible.
• Outside-Context Problem:
  • The Doom Slayer is this for everyone in MHA: He's quirkless yet still strong enough to take on All Might and win, wields weapons and technology far more advanced than anything they've seen, doesn't call his attacks or even speak period, and won't hesitate to brutally kill villains and criminals, but will NEVER harm an innocent. Even Nezu, for all his intelligence, is utterly perplexed by him.
  • He's also one for the Ascendant Realm. Before his arrival, they all thought he was just a myth, but his presence makes the deities of the Realm wary of him. It's later revealed the Dark Lord had already been defeated by the Creator a long time ago, and the Slayer himself is "unbound by fate", meaning they don't know why he's here nor what he will do, making him a massive enigma to the Realm. For now, they just watch events play out.
• Paint the Town Red: Or "island" in this case, as the Slayer's massacre of the Steel Sabers literally paint I-Island red with their blood.
• Pay Evil unto Evil: The Slayer ensures that the Villains pay for all the crimes they have committed with their blood.
• Pet the Dog: Despite being hindrances, the Heroes of My Hero Academia have earned the Doom Slayer's respect as he realizes they're good people and just doing their jobs by trying to stop him. However, they may have gained his respect but not his compliance; he won't kill them, but he's not afraid to rough them up if they try to get in his way.
• Poke in the Third Eye: Unintentional, but Ragdoll's attempts to mind scan the Slayer shattered her sanity to a point an Archangel had to fix her brain.
• Pragmatic Hero: Sayaka's decision to cover up David's involvement on I-Island and have him work with the HPSC wasn't done out of compassion or mercy, but only because he's more useful helping them out rather than rotting away behind bars for his monumental fuck-up.
• Precision F-Strike:
  • When finding out they can't do anything until the Prime Minister lifts the no-fly order, Mera becomes frustrated with the fact they couldn't do anything except watch the Slayer tear apart the Steel Sabers on the screens. When Sayaka tries to explain how the public would react, Mera drops this.
    Mera: Oh, right! The public! We certainly can't forget that they'll have fucking night terrors for the next 15 years after what they all saw on TV!
  • Vlad King is among the many Heroes who are left very traumatized and sickened by the corpses (or what remains of them) left by the Slayer. When Cow Lady insistently tries to get Vlad King moving to arrest the Slayer, Vlad King angrily throws an F-Strike at her and almost punched her until he realizes what he was about to do while everyone present is left shocked by his outburst.
    Vlad King: G-G-G-Give us a minute.
    Cow Lady: A minute?! Dang it, we don't have time for this! Y'all need to cowboy up and-
    Vlad King: I SAID GIVE US A FUCKING-!
  • Papa Prism does this to his last henchman when the henchman asked what his plan is.
    Henchman: What are you doing?
    Papa Prism: I'm calling the cops.
    Henchman: You're what?!
    Papa Prism: I'M CALLING THE FUCKING COPS!
• Pretender Diss: Doom Slayer is not impressed by Endeavor calling his flame Quirk Hellfire because he knows from experience that the real thing is much hotter.
• Public Execution:
  • In the Steel Sabers arc, the Slayer casually turns the Steel Sabers' ransom demand into a nightmare by brutally sawing the speaker in half while they were giving their demand in front of a horrified global audience before butchering as many Sabers in the shipyard, all while the camera is still filming the ensuing massacre until the Slayer destroys it. Mera remarks that the public will have night terrors for the next fifteen years because of the Slayer's antics.
  • The Bloody Bogans force Eel Boy to read their ransom demands before shooting him in the head when he's finished.
• Put Their Heads Together: The Doom Slayer does this to Loud Cloud and Mr. Brave, rendering them unconscious.
• Rage Breaking Point:
  • When Nine and his lieutenants find out Wolfram knew about the Slayer and didn't tell them, he was about ready to kill Wolfram for this had Curator not stopped him.
  • Mera utterly snaps when told they can't do anything during the Steel Sabers Arc, and when the Bloody Bogans start slaughtering civilians at Musutafu General, he outright tells Sayaka that because Nezu wanted to preserve the heroes' integrity by refusing to teach lethal force, they're now unprepared for extreme life-and-death situations like the ensuing.
• Rape Is a Special Kind of Evil: When the Slayer finds three hoodlums planning to rape Josei, the Slayer wastes no time butchering the rapists and then freeing Josei.
• Rapid-Fire "No!":
  • Marley does this when the Slayer views his pleas of surrender as an insult to those that died by their hands.
  • Camie ends up doing this when Inasa tries to fight the Slayer because there was no way the two could fight him on their own. Fortunately for them, the chefs explained their reasoning as to why he was here and the Slayer leaves the rabbit he rescued with the two.
• Reckless Gun Usage: When the Heroes start fighting back at the Bogans with lethal force, Yu Takeyama (Mt. Lady) grabs a pistol but she never used a gun before; she was taken aback by the gun's recoil which caused her to fire all her ammo into the ceiling. Rock Lock angrily chides her.
  Rock Lock: Are you fucking serious right now?!
  Yu: They make it look so easy in the movies!
• Reputation Apathy: One of the Slayer's defining traits. It doesn't matter that the heroes and villains want to catch him, only villain slaying does.
• Rewarded as a Traitor Deserves: Volcano repays Samuel Abraham for betraying David Shield by burning him alive.
• Righteous Rabbit: The first pro-hero the Slayer comes across is Miruko, who stops a robbery taking place in front of him. She sticks especially in the Slayer's mind due to her rabbit quirk reminding him of Daisy and her can-do attitude reminding him of his deceased wife Emily.
• Rivers of Blood: After the Slayer slaughters the entire Steel Sabers organization, the streets of I-Island are literally running red with the blood and guts of the dead and mutilated Sabers.
• Sadistic Choice:
  • The Slayer expresses genuine guilt over fighting the Pro-Heroes to escape I-Island and can't decide whether to feel bad for them or curse them for getting in his way. He accepts that they're good people, but he and VEGA had no choice but to go through them; it was either that or letting them capture and send him off to Tartarus, which is definitely off the table. The only saving grace he could give them was that he didn't cripple them for life.
  • Yagi finally chooses to reveal what the Slayer did on I-Island despite knowing the chaos that will come and protest from his comrades. There aren't any better options, and they owe it to the public as their defenders; all they can do is brace for the fallout.
  • The MHA world will inevitably find themselves between a rock and a hard place when The Legions of Hell come knocking under the orders of the Khan Maykr, where they must choose between using deadly force and let the Doom Slayer roam free or face extinction.
    • Some of the Heroes eventually begin using lethal force when their lives, along with many civilians, are put in danger during the Broken Vows arc, realizing that they're in no position to subdue or detain their enemies when the Bogans have gleefully massacred anyone in their path.
• Sanity Slippage: Ragdoll tries to scan the Slayer to find out where he is on I-Island, but all it gives her a vision of the literal Hell he’s faced, and you can likely guess what such visions would do to a person’s mind. Any signs of the quirky and energetic Ragdoll are effectively gone and in her place is a completely broken woman so consumed by fear of the Doom Slayer and what he’s faced that she nearly stabs out Miruko’s eyes with a scalpel in a fit of madness.
• Save the Villain: Izuku and Tenya stop the Doom Slayer from executing Shigaraki and try to reason him into turning Shigaraki to the police rather than killing him. This falls on deaf ears as the Slayer was still going to kill him, had Dabi not shown up and taken Ochako hostage.
• Saying Too Much: When Hawks mutters about All for One having a lot of influence, the Slayer and VEGA hear it and Hawks is forced to explain how he knows of him, partly to build up goodwill and largely out of fear he'll get knocked out.
• The Scream: One common response to seeing the Slayer, regardless if you're being rescued, hunted or even being butchered.
  • Shigaraki screams his lungs out when the Slayer casually rips his arm off. Ochako, Jiro, Mina and Mineta scream at seeing the act, moments before the Slayer proceeds to bludgeon Shigaraki half to death with said severed arm.
  • A teacher screams in terror as she sees the Slayer rip a Saber's throat out with his bare hands. Her students scream when seeing the blood-soaked Slayer.
  • All the airport hostages scream when they see the Slayer brutally decapitate four of their ground floor captors and then slice their last captor in half with a fire axe. The Slayer can't even blame them.
  • In Chapter 18, Ragdoll screams her lungs out when she sees the Slayer's eternal war against Hell.
• Screw This, I'm Outta Here: Curator and the Volcano Thieves accompanying him decide to leave I-Island after the Slayer's presence completely derails their plans, largely because their two options were to either be captured by the heroes, or brutally killed by the Slayer.
• Sole Survivor: Of the Insecticides' base being destroyed, only a 14 year old boy in their ranks is spared, though the gang leader was initially convinced the Slayer was gonna spare him before VEGA clarifies who they're talking to.
• Spanner in the Works: The Steel Sabers' initial plan was to occupy I-Island, steal all the technology, and 'ransom' off the hostages. The plan disintegrates as soon as the Doom Slayer makes them the victims of a gruesome Mook Horror Show after they try to establish a base in the abandoned subway tunnel the Slayer was hiding in.
• Spared by the Adaptation: Oboro Shirakumo is still alive and an active hero instead of being revived by All For One as the Nomu Kurogiri.
• Starts Stealthily, Ends Loudly: The Slayer's extermination of the Steel Sabers starts out like this, seeking to kill as many Sabers as he can without alerting the rest of the Sabers or their leaders to his presence, so they don't execute the hostages. Once he does his Public Execution and blows up their sub, it goes loud as the Slayer proceeds to hunt them down and kill them all.
• Story Arc: The story is divided into the following arcs:
  • Chapter 1-6: "Slayer"
  • Chapter 7-21: "Steel Sabers"
  • Chapter 22-31: "Premonitions"
  • Chapter 32-38: "Warpath"
  • Chapter 39-?: "Broken Vows"
• Superhero Packing Heat: Or vigilante according to the pro heroes in the Slayer's case. He's blessed with superhuman strength and speed and has a preference for really. BIG. GUNS.
• Talk to the Fist: Or the Super Shotgun, but when Curator tries to speak in front of the Slayer, the Slayer responds by quick-drawing his Super Shotgun and making it clear to Curator that he wants him and the Volcano Thieves dead. Volcano makes it clear to the rest of the LOV that the Slayer will not hesitate to kill them.
• Tear Off Your Face:
  • The Doom Slayer rips a Saber soldier's face off before smashing his head.
  • The Slayer grabs Slice's hair and tears it off along with her scalp and eyelids. Slice is spared from her agony when the Slayer smashes her entire head.
• Tears of Fear: Momo and Jiro suffer from this after witnessing the Slayer's massacre of the Sabers. This is a common answer, other than Stress Vomit, when it comes to the Slayer's brutality and massacres.
• Technologically Advanced Foe: The Doom Slayer's arsenal and Praetor Suit are among the most advanced pieces of technology in the MHA world, with Pro-Heroes shocked at some of the weapons he's got access to and not even a barrage of bullets or Endeavor's strongest attacks can break through his armor. The only person so far that's capable of making a dent in his armor (as in literally) is All Might, and even then only with his strongest attack. Even the Secret Weapons Investigation team in Langley quoted that "sane people do not build weapons like these" (if only they knew why…) as the weapons he wields are described as:
  • A laser pistol, being the EMG pistol.
  • A pump-action shotgun that can act as a grenade launcher, being the Combat Shotgun.
  • A belt-fed .50 caliber machine gun that can also shoot tiny missiles, being the Heavy Assault Rifle.
  • A rocket launcher with shrapnel-filled ordinance, being his signature Rocket Launcher.
  • An oversized sawed-off capable of blowing a man clean in half, being the Super Shotgun (though not the one nicknamed "Lucifer's Bane").
  • A portable, highly destructive railgun, being the Gauss Cannon.
  • A minigun that could transform into a triple-barreled monstrosity, being the Chaingun.
  • A fully-automatic energy rifle that can melt the skin off its targets, being the Plasma Rifle.
  • And, unbeknownst to the MHA world yet, an overly large energy gun that can shoot a large ball of green energy with lightning that can decimate just about anything with a heartbeat, being the BFG-9000.
• Teeth-Clenched Teamwork: Izuku, Ochako, Mirio, Shoto, Kirishima, Bakugou, Melissa and Miruko are forced into a tense alliance with the Slayer and VEGA during the Steel Sabers Arc.
• Tempting Fate: Multikill, hopped up on cocaine and armed with all the guns his 20 arms can carry, screams out that he's ready. Cue the Slayer breaking through the skylight with his great Katana communicators. When the Burnin' Sidekickers arrive, they see a clearly terrified Multikill backpedaling while firing at the Slayer with all the guns he has, moments before the Slayer cleaves him in half.
• Terrifying Rescuer: A heroic example with the Doom Slayer. The captives on I-Island regard him with absolute terror after he brutally dispatches their captors, and anyone he rescues in the Warpath Arc are terrified of him for his brutal disposing of criminal gangs.
• Terror Hero: The Doom Slayer quickly establishes himself as the single most brutal vigilante in Japan due to his propensity for excessive violence stemming from his eons-long battle against the demons of Hell. Ochako is mentally scarred for life after witnessing him tearing off Shigaraki's right arm with his bare hands, All Might is stunned by the Slayer's sheer brutality after having seen nothing like it in his long career, and the Slayer more or less traumatizes the rest of Class 1-A after tearing apart the Steel Sabers on I-Island.
• There Is No Kill Like Overkill: While any of his weapons could have worked just fine in taking out both Dabi and Shigaraki, the Slayer decides to pull out a rocket launcher. Thanks to the villains getting rescued via Kurogiri's portal, the rockets cause mass destruction inside the mall, though thankfully, no one was hurt.
• This Cannot Be!: The League of Villains are shocked to witness the Pro Heroes holed up at Mustafau General Hospital using lethal force against the Bloody Bogans on live television, with Spinner spiraling into panic at the very real prospect that the Heroes will kill them all for their crimes.
  Spinner: They wouldn't do that. They can't do that. They don't have the willpower...they're supposed to be cowards...!
• Thousand-Yard Stare: Everyone develops this when cleaning up or seeing the Slayer's "work". Best exemplified when heroes and JSDF personnel arrive and venture deeper into I-Island, only to find that the Steel Sabers were reduced to literal human salsa, and they only become more and more traumatized as time goes on.
• Thou Shalt Not Kill: The Pro Heroes take serious issues with the Doom Slayer's "excessive" methods and cannot allow him to roam free for this.
  • The Steel Sabers exploited this moral code, as according to Nine, this code is their weakest point. It made it easy for the Sabers to butcher 246 heroes.
  • Toshinori Yagi/All Might had considered killing All For One in the past but refused. But after his powers are severely diminished from his battle against the Doom Slayer, Yagi realizes that All For One is too dangerous to be left alive and swears to kill him when he faces him again.
  • When talking with VEGA and the Slayer, Hawks concedes that All for One is too dangerous to let live, and secretly admits that the Doom Slayer is more than likely capable of doing the job.
  • By the time of the Broken Vows arc, the Heroes finally ditch this once it's clear that the Bloody Bogans cannot be taken down non-lethally.
    Edgeshot: We cannot exercise restraint anymore, and we can't hold back on our Quirks. It is now kill or be killed.
• Time Dissonance: Due to his literal eons fighting against The Legions of Hell, the Slayer's perception of time is fucked 8 ways to Sunday, so when VEGA tells him it'll be 70 years before he can build a working teleporter, the Slayer doesn't mind the wait. Though that's offset by the Slayer's new mission: kill All for One and every villain that gets in his way.
• Token Good Teammate: Twice is one of the few (if not the only) morally scrupulous members of the League of Villains, best exemplified when he's shown to be deeply uncomfortable hanging out with some of the more bloodthirsty and sadistic members of the League.
• Too Dumb to Live:
  • At the end of Chapter 15, Nine, Slice, Mummy and Chimera head down to fight the Slayer. He brutally kills them all.
  • In Chapter 18, Volcano fires a tidal wave of magma at Izuku, Ochako, Shoto, Melissa and Mirio, hoping to kill them all, but forgot that Melissa was holding the VX rocket. Had the Slayer not used himself as a Human Shield, Volcano would've also condemned his team and Curator to a nasty death. Curator even glares at Volcano for the idiotic stunt he pulled.
  • After the Slayer beats 48 heroes, including All Might, Bakugou decides to try and attack the Slayer - despite the fact that A: he just killed an entire mercenary organization, B: beat up nearly 50 heroes, and C: with the exception of All Might-based strength, literally nothing can break or dent his armor. Predictably, Bakugou gets captured and tries to launch another attack, without checking if there's anything flammable in the vicinity. Had All Might and Miruko not panicked, Bakugou would've succeeded where All for One failed in killing All Might alongside himself and Miruko.
  • When Don Puru sees a shadowed silhouette one floor above his casino, he assumes this to be the case and tells the guy that there are other ways to get himself killed if he's looking to die. Unfortunately for him, it was not some wannabe hero, but the Doom Slayer.
  • Inasa decides to try and fight the Slayer, despite Camie explaining to him that it is a bad idea. Instead of getting knocked out, he gives them a rabbit he rescued.
  • Bakugou, again, proves that he didn't even learn from his mistakes and escaped from his house to get to Musutafu General. It's heavily implied that he will not have a good time if he survives. For reference, a commenter on AO3 lampshaded that even Izuku isn't dumb enough to pull a stunt like that and is convinced Bakugou is signing himself up to be on the Darwin Awards.
• Translator Microbes: The Slayer use his helmet to translate Japanese words in English. Because if the helmet is removed off his head:
  Chapter 21: The still-conscious Slayer listened in on them from within his confines as the black fumes wafted around him. He could not understand what they were saying since he needed his helmet to help him translate Japanese.
• Traumatic Superpower Awakening:
  • In chapter 41, after the Bloody Bogans killed some people, including Eel Boy (after he said the gang's message through the megaphone to Pro Heroes and police on the streets around the hospital), Miruko was so furious that she underwent a Quirk Awakening, greatly increasing her strength, durability, and pain tolerance.
  • Chapter 43 has Vlad King unconsciously awaken his Quirk to drain the blood of the Bogans attacking his fellow Heroes, leaving him even more traumatized than he already was.
  • Chapter 44 has Ryukyu, Cementoss, Death Arms, Bubble Girl, and Loud Cloud awaken the full potential of their Quirks after they witness Fourth Kind, Mr. Brave, and Centipeder get blown up by claymore mines the Bogans set up, each respectively gaining the ability to partially transform into her dragon form, transform his limbs into concrete-based weaponry, turn his skin into cast iron armor, use bubbles as powerful explosives, and create miniature thunderclouds capable of electrocuting enemies to death.
• Troll: The Slayer can't help but indulge in this when he's faced with opponents that are too big for their britches. Most notably, his "fight" with Endeavor in Chapter 20 consists of the Slayer just letting the Pro Hero ineffectively pelt him with his most powerful attacks before casually wiping nonexistent soot off his armor just to mess with him. Then, he not only lets Endeavor pummel him, he walks backwards to make Endeavor think he's doing damage. After the Slayer has his fun, he humbles Endeavor.
• Troubled Fetal Position: At the end of Chapter 25, both Ragdoll and La Brava are curled up into fetal positions. The former having read the Doom Slayer's mind and lost hers in the process, while the latter had a front-row seat to see the Slayer not only butcher 10,000 people, but even defeat every single hero that fought him, including All Might himself.
• Unscrupulous Hero: Subverted. The violence Slayer unleashes against Villains is nearly unheard of, with only Chizome Akaguro, whether as Stendhal or Stain, ever coming anywhere close to Slayer's level of brutality. However, unlike Stain or any other Villain for that matter, the Slayer still has morals and is heroic in his own incredibly bloody way, never once leaving innocents to die or turning his violence unto other Heroes who're trying to stop him, despite being otherwise confounded by the Heroes' own moral code more than anything.
• Unusually Uninteresting Sight: At first, the populace of Musutafu is unconcerned about a tall guy in power armor walking among them, believing him to be another Pro-Hero. That quickly changes after he nearly blows up the mall "fighting" Shigaraki.
• Use Your Head: Wolfram meets his end after the Slayer reduces his head into Ludicrous Gibs with a series of brutal headbutts.
• Villain Killer:
  • The Slayer officially becomes one after slaughtering Nine, Wolfram and their underlings on I-Island.
  • The Pro Heroes holed up at Mustafau General Hospital during the Bloody Bogans' attack eventually come around to lethal force, tearing through the psychopaths with bloody results.
• Villains Want Mercy: Many villains on the receiving end of the Slayer's wrath desperately beg and plead for their lives, only doing nothing more than piss him off even more. The only person the Slayer spared is a young boy belonging to a Villain gang in which he and VEGA easily convinces him to never join a gang and rethink his life.
  Gang leader: WAITWAITWAIT! DON'T KILL ME! I'LL PAY YOU DOUBLE! TRIPLE! WHATEVER YOU WANT!
  VEGA: We are not going to kill you.
  Gang leader: Y-y-y-you're not? Oh, thank God-
  VEGA: We were not talking to you.
  The Slayer tears the man's head off.
• Vigilante Man: The Slayer is treated like one by the Heroes and Villains alike after his encounter with Shigaraki.
• Villainous Breakdown:
  • Shigaraki really loses it during and after barely surviving his encounter with the Slayer, cruelly disintegrating the same doctor who saved his life.
  • In Chapter 16, after the Slayer kills his entire organization, Slice, Mummy and leaves him badly bleeding and injured, Nine rants about all his achievements and yells that he won't lose to an unknown vigilante. The Doom Slayer isn't impressed at all by the little tirade and internally calls him a friggin' baby while wondering how the hell the heroes had so much trouble nabbing the guy in the first place.
• Villain Takes an Interest:
  • It doesn't take long for the Slayer to draw All For One's attention, to the point he even thinks about persuading him to join the League. Or at least, steal the man's "Quirk", unaware that he doesn't have one. Or that he is on the top of the Slayer's kill list.
  • Curator is left mesmerized by the Slayer's brutality and merciless slaughter of the Steel Sabers and Chainsaw, seeing it like a "ballet of carnage" and "gory poetry in motion".
  • An anti-heroic example shows up when Lady Nagant also takes an interest in the Doom Slayer after seeing his carnage on I-Island on live TV, calling him "a man after her own heart".
  • Another heroic example, The Four Horsemen of the Apocalypse became interested in making the Slayer a new Horseman after witnessing the massacre, however, War believes he will respectfully decline the offer.
  • Played a bit straighter with the mysterious doctor that Miruko runs into while departing Mustafu General Hospital, who is revealed to be none other than Loki.
• Violence Is Disturbing: The Slayer inflicting so much bloody carnage is treated this way in the eyes of the heroes, with Class 1-A absolutely horrified by the Slayer's actions, to the point Uraraka develops post-traumatic stress disorder from witnessing how he deals with Shigaraki.
• Well-Intentioned Extremist:
  • This what the Doom Slayer describes the chairman of the UAC, Dr. Samuel Hayden, as despite being calculating, manipulative, and dangerous, he has humanity's best interests at the end.
  • The same could be said for the Doom Slayer as well.
• We Need a Distraction: The Slayer and VEGA do this quite frequently.
  • During the airport incursion, VEGA has a drone do wheelies to attract the ground floor Sabers to look at it in confusion so the Slayer could rush in, skewer the top guards and then kill the ground floor sabers without the Sabers responding by gunning the hostages down, which works like a charm.
  • When going loud, the Slayer makes his way to the I-Island expo by hurling a double-tanker full of gas at the Sabers in the Expo and then deploying a hologram grenade to make them focus on the hologram. They only figure it out when they see the Slayer disembowel one of the sniper teams with his Great Communicator.
  • To get the captured Ketsubutsu students and their unconscious teacher away from what will be a bloody nightmare, the Slayer snipes Stripped Bolt's head off and runs off while Flipping the Bird at his gang, leading to the gang forgetting about the group of hero students to focus on the man that becomes their end.
• Wham Episode: Chapter 39. Pro Heroes have a reprieve in Musutafu General Hospital, only for the place to come under attack by the Bloody Bogans on All for One's orders. Once they receive word on the attack, the Doom Slayer and VEGA quickly understand that AFO used their attacks in the Warpath Arc as a distraction to active Heroes and police, enraging the Hellwalker with the revelation that All for One managed to outsmart him and his AI companion.
  Chapter 39: Silently snarling, the Bane of Hell revved up the Rampart and throttled down the road as fast as his vehicle could go. Heads were going to roll.
• Wham Shot: In chapter 38, the Four Horesmen finally found a missing piece of the Helix Stone in the shop of Vulgrim and Dis:
  Chapter 38: The mural depicted what appeared to be the Doom Slayer standing upon countless Demon skulls but there was something significantly different about it. For one, the figure was distinctly female and appeared to be wearing a fur cape. She was raising a flail in the air in one hand while the other hand held a bladed shield. But the most glaring feature the Horsemen noticed…
  Was the pair of long, rabbit-like ears on the sides of the figure's head.
• What a Drag: Eraserhead is dragged along the pavement by the Doom Slayer when he attempts to capture him with his capture tape, forcing him to let go to avoid getting burns from the extreme friction involved.
• What the Hell Are You?: The last surviving Steel Sabers mercenary spent his last moments screaming this at the Doom Slayer while desperately and futilely shooting him before being obliterated via Super Shotgun.
• What the Hell, Hero?:
  • When Endeavor hears that Mirko and Fatgum had encountered the Slayer before, he angrily demands to know why they didn't try to bring him in then. Mirko fires back that the worst he did was stop a petty robber, and the way he did so wasn't in any way an indication of the sheer, unrelenting chaos he would later prove capable of. Further, she states that she can't remember every single hero in Japan, so she didn't know he was a vigilante, and not some random local hero that she's never heard of while also pointing out that Endeavour is the last person to criticize her, considering his own failures and history of violent behavior.
  • A horrified Mirio voices his outrage over the Doom Slayer's massacre of Specs, Swordkil, Nobu, and Daigo.
  • VEGA (in a gentler tone than usual for this trope) calls out Izuku's naivete when he attempts to intervene in the Slayer's battle against Wolfram on I-Island, pointing out that letting villains like the Steel Sabers live not only would be stupid, but would also spit on the families and loved ones of those whom the mercenaries murdered.
    Izuku: I'm going back up the roof. Miruko needs support and I don't trust that Vigilante.
    Mirio: Izuku, no! It's too dangerous to go up there!
    VEGA: I would advise against this course of action, Mr. Midoriya.
    Izuku: I have to stop him from killing that Villain! It doesn't have to end that way! Just let me remove that headset and restrain him so I can take him to the authorities!
    VEGA: Wolfram has become a danger to everyone on the island and now poses a significant threat. Attempting to subdue him via non-lethal methods is impossible at this point and he therefore should be eliminated.
    Izuku: No! He doesn't have to die! You-I mean, he can't just solve every problem with extreme violence!
    VEGA: That much is true. But in this case, Wolfram is beyond the point of mental recovery and-
    Izuku: STOP IT! ENOUGH OF THIS! ALL THIS DEATH AND BLOODSHED, HE CAN'T KEEP KILLING PEOPLE LIKE THIS! HE CAN'T!
    [Beat]
    VEGA: The people you were referring to were mercenaries and Villains who were planning on murdering innocent civilians. By the time the Pro Heroes came here to stop them, they would have killed all the hostages along with the Heroes and escape with I-Island's Support Items to use for their own purposes. There was no alternate solution to resolve the solution peacefully. We did what we had to do.
    Izuku: B-But it's still not right!
    VEGA: Then would it be 'right' to let them escape after committing what amounts to a small-scale genocide?
    Izuku: But-
    VEGA: Would it be 'right' to let the Steel Sabers to continue hunting down Heroes?
    Izuku: That's not what I meant-
    VEGA: Would it be 'right' to let families suffer from their actions?
    Izuku: I-
    VEGA: Would it be 'right' to not eliminate them in order to prevent them from endangering more people?
    Izuku: ...!
    VEGA: The world is not black and white, Izuku Midoriya. It is gray.
  • Miruko is also on the receiving end of this from VEGA regarding her reckless tactics as a superhero.
    VEGA: If I may inquire, Ms. Usagiyama, why do you refrain from avoiding potentially lethal attacks?
    Miruko: Huh?
    VEGA: You were perfectly capable of dodging any of Wolfram's strikes but you instead choose to throw yourself directly into their path, risking mortal if not fatal injuries. Why is that?
    Miruko: Why do you care? Well, if you're that curious, being a Hero doesn't come without risks. There's a real chance that you could die in the line of duty, but that doesn't bother me one bit. I don't care if I lose a limb or two as long as I get to pummel whatever Villain comes my way. You think that guy was going to end me? I live every day of my life like there's no tomorrow so when my number's up, I can clock out with no regrets.
    VEGA: That is not a healthy mindset, Ms. Usagiyama. You should make an effort to avoid purposefully injuring yourself and so that you may better combat your opponent:
    Miruko: What?! I should be taking lessons from a walking tank and his pet computer program?!
    VEGA: You should not throw your life away so recklessly. Think about what you can do more for society in the future rather than focus on the impression you leave on others if you were to fall in battle as a result of your inability to avoid fatal harm.
    • Recovery Girl and Hawks also gives her similar speeches.
  • Hawks gives Bakugo an earful for charging into Mustafau General Hospital with no plan whatsoever just because he wants to assuage his bruised ego, pointing out that heroes are far from invincible. Unfortunately, Bakugo is far too arrogant and bullheaded to even listen, forcing Hawks to knock him unconscious before he gets himself killed by the Bloody Bogans.
• Willfully Weak: When it comes to the Heroes, the Slayer intentionally holds back as if he went all out on the heroes, they would be crippled for life if they're lucky, if not outright killed.
• Worthy Opponent: Taggart ends up seeing Toshinori Yagi/All Might as one, because of his willingness to force himself beyond his time limit for using One For All and for denting his armor.
• Wrong Context Magic: Everyone mistakenly assumes that the Doom Slayer is a Quirk user due to his inhuman strength and capabilities. It was not until after Eraserhead failed to subdue him that they realized he didn't have one.
  • Some villains guess the Slayer is actually some kind of ultra-top secret black-ops human weapon that is only sent out when the villain problem gets too out of hand.
  • Even AFO believes the Slayer has the most powerful Quirk on the planet, one capable of defeating All Might, and literally salivates at the thought of taking it for himself. He'll be in for a rude awakening when that fight happens...
• Xanatos Gambit: It's surprising for a Big Bad Wannabe like this version of AFO, but he sets up a great one during his plan with the The Blood Bogans: If Slayer had ignored the other gangs that he took on a warpath, more casualties would have happened, which would allow AFO a victory. However, since he didn't, AFO still wins, since it stretched the police and heroes thin, allowing the Blood Bogans free rein of the hospital where the heroes are.
• You Have Failed Me: Curator and the Volcano Thieves failed in their task of stealing the Quirk Amplification Headset thanks to the Doom Slayer, and they rightfully feared that AFO would kill them for their failures. But to their surprise, AFO doesn't see the point in punishing them as he lays the blame on Wolfram and that no one have foreseen the Slayer would get involved. Furthermore, it turns out that AFO got what he wanted when Volcano remembered that he managed to smuggle blueprints for the QAH.
• You Have Outlived Your Usefulness: Sam Abraham is immolated by Volcano after he helps him get the Quirk Amplifier Headset.
• You Remind Me of X: For the Slayer, Miruko reminds him of his deceased wife Emily, and his pet rabbit Daisy.