Fanfic / The Abomination Quirk

Izuku Midoriya has been bullied since preschool for being Quirkless. After all, the doctor's report showed an extra toe joint! Bakugou doesn't join in. After all, a Quirkless person doesn't have four tentacles that can liquefy and devour a grown man in seconds growing out of his back...

— AO3 Summary

The Abomination Quirk is a fanfic written by The_Plauge_Dragon on Archive of Our Own.

Instead of being born Quirkless, Izuku is born with Alex Mercer's powers. This changes his life in many ways as he grapples with the fact that his Quirk makes him a cannibalistic Humanoid Abomination while he strives to be a hero. To make matters even more complex, there's the fact that All For One, All Might's archnemesis, is his dad, complicating his life even further as he forges his own path through hero society. Luckily for him, he's got friends he can count on to make sure he doesn't stray from his dream to be a hero.

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The Abomination Quirk displays examples of:

• Abled in the Adaptation: Tensei is not outright crippled by Stain in this continuity due to Stain deliberately choosing to simply injure him enough so that Tensei can retire from heroism and live a normal life.
• Adaptational Badass:
  • Izuku dual-wields One for All in conjunction with Blacklight, making him a Physical God in all but name.
  • Aizawa receives a set of nictitating membranes from Izuku's Blacklight infusion during the USJ attack, allowing him to maintain his Power Nullifier abilities for far longer in combat.
  • All Might is able to remain in his muscular form for longer after Izuku injects his own biomass into him, enhancing his physical endurance to the point that he still can fight even after losing One for All.
  • Inko used to be a Vigilante who went by the name of Heartthrob before she married Hisashi and had Izuku.
  • Bakugo learns how to create thermobaric explosions with his Quirk.
• Adaptational Heroism: Surprisingly enough, Overhaul gets this treatment. In canon, he sought to use Eri's power to launch a revolution to eliminate all Quirks from society and treated her like a mere guinea pig. Here? He treats Eri like his own flesh and blood daughter and strove to make a Cure for Cancer with her saliva, even entrusting her safety to the Heroes after Nouziri Auri takes over the Shie Hassaikai.
  • Overlaps with Adaptational Nice Guy for Stain, who in this continuity leans closer to Anti-Hero with his crusade against legitimately corrupt heroes who abuse their positions to commit crimes.
• Adaptational Nice Guy:
  • All for One (a.k.a Hisashi Midoriya) is still the villainous mastermind from canon that we all know and fear, but he's also a family man who does everything in his power to keep his wife and son safe and happy.
  • Bakugo is much nicer towards Izuku and is much less arrogant than canon after Hisashi gave him a thinly-veiled threat to stop picking on his son or suffer the consequences.
  • Stain, while still a Knight Templar as per canon, is not as Ax-Crazy and even becomes Izuku's Spirit Advisor after he's absorbed into him.
• Adaptational Villainy: Endeavor is much worse than canon thanks to his naked ambition and willingness to use underhanded/outright illegal methods to ensure that he becomes the number one hero in Japan.
• Always Someone Better: Bakugo knows that Izuku outstrips him (and by extension everyone) by a ridiculous margin just by having Blacklight as his Quirk and makes sure that they know that.
• And Show It to You: Inko's modus operandi as Heartthrob was to use her telekinetic powers to tear out the hearts of Villains.
• Asshole Victim: All for One often does this whenever he deals with people who dare threaten his family, such as the Sludge Villain and the scummy counselor.
  • Muscular and Moonfish are Eaten Alive by Izuku during the training camp invasion. Given how both are both complete psychopaths, no one is too hung-up about their deaths.
• Attention Deficit... Ooh, Shiny!: Namedropped word-for-word by Shinso in regards to Nejire Hado thanks to her hyperactive, off-the-wall behavior.
• Badass Family: The Midoriyas, given that the dad is Japan's most infamous supervillain, the mom's an ex-vigilante, and the kid's a walking mass of virus cells in the shape of a human being who still wants to be a hero.
• Beware the Nice Ones:
  • Inko may be a sweet and loving woman, but there's a damn good reason why even hardened pros like Eraserhead and All Might are terrified of her.
  • Weirdly enough, Masaru Bakugo is somehow capable of cowing All for One despite being the weakest member of his family!
• Body Horror: All too common due to how Izuku's quirk works.
• Canon Discontinuity: In-Universe, the [PROTOTYPE] series had a series of sequels that effectively ignored [PROTOTYPE 2] in favor of directly continuing from the original game.
• Cold-Blooded Torture:
  • The Sludge Villain is on the receiving end of this courtesy of Hisashi for daring to even think of harming his family.
  • The guidance counselor who belittled Izuku for being supposedly Quirkless also gets tortured by All for One before he has Shigaraki disintegrate him, and slowly at that.
• Crazy-Prepared: Hisashi effectively made his son functionally immortal by creating sweaters infused with Izuku's hair fibers capable of conducting Grand Theft Me on their wearers in the event that someone managed to actually kill him.
• Creepy Good: Izuku, by virtue of his Lovecraftian Superpower and relation to All for One.
• Curb-Stomp Battle:
  • Muscular doesn't even stand a chance against Izuku in his "fight", getting his arm cut off before he's Eaten Alive.
  • Nozuiri Auri is instantly defeated by Stain after she ends up in Izuku's mind, with Stain telling her that Izuku "played her like a God. Damn. Fiddle."
• Darker and Edgier: The seedier aspects of hero life are brought up in this fic, chief among them corrupt heroes who abuse their positions to commit horrible crimes with impunity.
  • Corruption within hero schools is brought up within the story, with the amount of clout Mineta's father has in the government and the Black Semester scandal mentioned by Stain being two prominent examples.
  • Stain reveals that all the restrictions on Quirk use in public are products of the Cabal's Evil Plan to slowly convert the world into a Police State with them at the top as revenge for their fall from power.
• Dark Is Not Evil: Izuku's quirk is literally Blacklight (as if the "black" in its name wasn't obvious enough), yet he has nothing but the best intentions for everyone.
• The Dreaded: Along with All for One, Inko is this among the heroes for her track record as a Vigilante before she settled down.
• Everyone Has Standards:
  • Denki warns the 1-A girls about Mineta's cheerleader scheme because even he finds that a bridge too far for him to cross.
  • Mineta is immediately dropped from the Hero course to General Studies after everyone witnesses his actions at the Sports Festival, only escaping expulsion thanks to his dad's numerous connections in high places.
  • For all his Knight Templar tendencies regarding his outlook towards heroes, Stain has nothing but utmost respect for rescue heroes for the work they do and tears into the League of Villains when they state their reason for attacking the Pussycats.
  • Izuku is horrified at the possibility of killing innocent people when he finds out about his dad's contingency plan for him. Learning that the sweaters were deliberately sent to criminals only lessens his repulsion by a little bit considering that he'd still be eating people to resurrect himself.
  • When Yo Shindou demands that Inasa defeat Gang Orca even it it means committing Unfriendly Fire on Izuku during the provisional Hero license exam, Gang Orca makes his displeasure at hearing someone threaten their fellow trainee very clear.
• Evil Hero: A major component of Stain's goal was to purge society of heroes who abused their positions to commit crimes while avoiding punishment under the law. Mole, Gazer, Vulture, and Gryphon were but a few of his targets that he killed for their crimes.
  • Endeavor practically embodies this trope to the point that he's laughing like a maniac when he receives the news that All Might is no longer number one.
• Evil Is Petty: Endeavor calls and threatens everyone who wished to send Izuku an internship offer with lawsuits and possible threats of framing for crimes. Why? Because he bested Shoto in the Sports Festival.
• "Facing the Bullets" One-Liner: Stain gives one to the group of heroes led by Endeavor before sacrificing himself to heal Izuku after he saves him from the Nomu that captured him.
  Stain: Endeavor. You are at the top of my list, and you know it. I know you aimed to take out three threats with one go… I won’t let you. This child will be my legacy! Let it be known that the Hero Killer died saving the life of an innocent a ‘hero’ deliberately tried to kill! (impales himself on Izuku's feeding tendrils) This is my final act.
• Greater-Scope Villain: The Cabal, an international conspiracy founded by ex-Chinese Communist Party members, serves as this for the fic as a whole a la HYDRA with their infiltration of governments around the world and other things.
• Half the Man He Used to Be: Izuku invokes this as part of his and Bakugo's strategy against All Might in the practical portion of finals. It works a little too well against him.
• Heroic BSoD: Izuku has one when Recovery Girl informs him that his Quirk has effectively made him non-human after his match against Shinso.
  • All Might nearly breaks down after he seemingly kills Midoriya during the final exam before the latter reveals his bluff.
  • Inko breaks down into tears when she learns that Hizashi was All for One all along.
• Humanoid Abomination: Blacklight effectively makes Izuku a sentient mass of viral biomatter in the shape of a human.
• Horrifying Hero: Izuku wants nothing more than to be the greatest hero despite being a Humanoid Abomination.
• I Gave My Word: All for One releases Bakugo from capture after the latter swears by his family promise to serve Hellfire Katsudon if he and Inko were to ever divorce to never join the League of Villains.
• I'm a Humanitarian: Blacklight pretty much runs on this to ensure that Izuku has enough biomass to stay alive and use his Quirk effectively.
• Implied Depowering Threat: Hisashi threatens to steal Bakugo's quirk from him in front of the explosive blonde to make him stop bullying Izuku.
  Hisashi: I’ll have you know that my brother was Quirkless. He wanted to be a hero, too. And do you know what happened? He got his wish. He became the world’s greatest hero at the time. And then he died a hero. So, when you grind those without a Quirk into the ground, most of me is begging you to continue, so I can make you live that nightmare. Remember this talk, Katsuki, because if this happens again, I won’t give you another warning. Now go apologize.
• I Need a Freaking Drink:
  • Izuku causes Aizawa no shortage of mind-bending confusion with his Quirk and how he conducts himself, but Inko chewing him and All Might out over what had happened with the training camp invasion scares him so badly that both men decide to go drinking just so they can try to forget the sheer terror from that experience.
  • Tomura Shigaraki asks Kurogiri to give him the strongest alcoholic drink available in his bar after he finds out that not only is Izuku All for One's son, but Inko Midoriya (aka Heartthrob) is AFO's wife. Kurogiri later joins in on the drinking after Shigaraki reveals those tidbits to him.
• Internal Reveal: All Might reveals to Bakugo that Hisashi Midoriya is indeed All for One in chapter 25.
• Innocent Innuendo: During the Battle Trial against Iida and Uraraka, Bakugo reassures Izuku that he won't accidentally kill Iida with his quirk. Unfortunately, his choice of words in his reassurance causes the rest of 1-A to use him as the butt of their jokes.
  Bakugo: DEKU! I heard that through the radio! Kick his ass and get up here!
  Izuku: But I might kill him!
  Bakugo: Then focus on the kicking of his ass, not the eating of his ass!
• In Spite of a Nail: Even though Tensei avoids being crippled by Stain, he's still forced to retire from heroics due to his injuries.
  • Izuku still gets only Gran Torino for his internships despite placing second, with Shoto explaining his father intentionally sabotaged Izuku's internship offers to his class.
  • Tenya Iida still goes after Stain for attacking his brother Tensei even though Stain did that to protect him from all the criminals and villains who would go after his head for his heroic deeds.
  • Bakugo is still kidnapped by the League of Villains during the training camp invasion.
• It's Personal: All for One hates All Might for depriving him of the opportunity to be with his family ever since their climatic fight five years ago.
• Jerk with a Heart of Gold: Bakugo, while still a bit abrasive, is a much kinder person towards others thanks to Hisashi's influence.
• Like Father, Unlike Son: Hisashi is bar none the most infamous villain of Japan and the boogeyman of society. Izuku, on the other hand, aims to be a hero despite being All for One's son.
• Lovecraftian Superpower: Blacklight is basically this as per its appearance in the [PROTOTYPE] series.
• Mama Bear/Papa Wolf: Inko and Hisashi are highly protective towards Izuku and are willing to take on anyone who threatens their family.
• Mood Whiplash: It's quite incongruous to see Izuku be an utter savage in combat one moment and his usual sweet self the next, as anyone who knows him can testify.
• Oh, Crap!: Bakugo has this reaction when he sees that Izuku showed up to save him from the Sludge Villain. Given his previous experiences and what happens next, it's hard to blame him.
  • Muscular gets the same when Izuku tells him what his Quirk really is right before his death.
  • Ditto for Izuku when he realizes that the League of Villains used his blood to make Redlight
• Once Done, Never Forgotten: Class 1-A constantly reminds Bakugo of the one-liner he said during the training match he and Izuku had against Iida and Uraraka during their Battle Trile, much to his embarrassment. It dissipates once they understand what he meant by "eating his ass".
• Pædo Hunt: When they were just little kids, Izuku and Bakugo were almost raped by a pedophile who was after them before Izuku's quirk decided to manifest itself.
• Pet the Dog: All for One, Japan's most infamous supervillain, is also the owner of Gullet's Heaven, a restaurant that provides Quirkless people with a steady paycheck and a safe working environment.
• Pre-Mortem One-Liner: Izuku gives one to Muscular right before he turns the latter into Blacklight chow.
  Muscular: Y-you’re a hero! You shouldn’t k-kill!
  Izuku: Guess what? I already have a body count.
• Put on a Bus: Mineta is rerouted to General Studies after his perverted antics during the Sports Festival and has never been seen since.
• Overt Operative: The Cabal spies who were tailing Izuku were wearing their organization's bright red, yellow star-emblazoned uniforms, which did them no favors for evading Shigaraki.
• Related in the Adaptation: All for One is Izuku's dad.
• Shout-Out: Bakugo and All Might quote Jotaro and DIO's iconic exchange word for word in their fight during the final exams.
• Sir Swears-a-Lot: Bakugo still has something of a potty mouth even after Hisashi guided him into being a nicer person.
• Sins of the Father: Sir Nighteye is none too happy about Izuku interning at his agency due to his supposedly Villainous Lineage.
  • When Stain argues with Nighteye over the whole Villainous Lineage, he tells him that Ditto, a corrupt Pro Hero he killed, intentionally framed the children of criminals with the crimes Ditto himself committed.
• Seen It All: Bakugo notes that being around Izuku's pretty much desensitized him to cannibalism when he has to fight Moonfish with Todoroki.
• The Sociopath: Stain notes that one has to be medically tested as a sociopath in order to have a high-ranking position in the Heroes Public Safety Commission.
• So Proud of You: All for One is ecstatic at his son's performance during the Sports Festival to the point that the silencing barrier he set up around him is pushed to its limits from his cheering.
• Spared by the Adaptation: Sir Nighteye is healed of his near-fatal injuries by Overhaul, averting his death in the process.
• Talking Is a Free Action: Averted thanks to Hisashi's training emphasizing why it's a bad idea to go off into long monologues. Bakugo and Shinsou even lampshade how ridiculous that trope is during joint training.
  Shinsou: Man, that training paid off! And no one seems to realize that talking isn’t a free action!
• Talk to the Fist: Hisashi pretty much trained Izuku to use this in fights to exploit the free time enemies give in monologuing.
• Terror Hero: Practically name-dropped by Uraraka when everyone else witnesses Izuku's ferocity against the simulated villain attack during joint training.

Uraraka: I think he’s going for the… what was it? Terror Hero? He’s putting the fear of God in the villains… it’s a bit like All Might, if you squint. He’s basically saying they have no chance, and he’s trying to make sure that they know it.

• "The Reason You Suck" Speech: Izuku practically calls Shoto out on refusing to fully accept his quirk just because of his grudge towards his dad.
  Izuku: I noticed that you’re trembling, Todoroki. You’re cold, aren’t you? After all, there has to be a limit to how much your body can take. And you could easily use your left to take care of that, right?
  Shoto: Like you’re one to talk. I know you’re not even fighting at half strength.
  Izuku: You want me to fight with all I have? Really? (...) Very well, but I expect you to do the same.
  Shoto: Did my old man buy you off!?
  Izuku: Quite the opposite, actually, but that doesn't matter. I’ll have you know that they’re immune to cold. I tested it out when I was younger. I stuck them in a freezer. Nothing happened.
  Shoto: You sound like you don’t like them.
  Izuku: And why would you think that? Is it because you know damn well what they’re for!? (walks menacingly towards Shoto)
  Shoto: Why are you doing this?!
  Izuku: You wanted me to give it my all, so here I am, doing just that. (...) What? Are you not going to as well? Is that it from you, Shoto Todoroki? Are you just gonna refuse to use your full power? Are you going to handicap yourself just because you think your Quirk is too much like your father’s? Well, news flash! It’s not his! It’s your Quirk!
  Shoto: You know nothing!
  Izuku: Wanna know something? In spite of my Quirk, I have an extra toe joint. And somehow, that knowledge was leaked out. I had to deal with the stigma of being Quirkless throughout my life, with only Kacchan, his family, and my family knowing otherwise. I’ve had to deal with bullies, both from students and teachers. Heck, there was only one teacher who didn’t see me as garbage! She stood up for me! That year was the only year where I didn’t have to repeat a certain mantra in my head over and over! Wanna know what is was?! (Cheshire Cat Grin) ‘Don’t hurt them! Don’t hurt them!’ You, Shoto, know nothing of the hell I’ve put myself through in an attempt to keep those who despised my existence alive! So, are you gonna use your fire? Or are you gonna lose? Either way, I have to thank you.
  Shoto: T-thank me?
  Izuku: (Slasher Smile) Thank you for such WONDERFUL comedy!
  • Bakugo chews out the League of Villains for being whiny Entitled Bastards who just want to watch the world burn when Shigaraki begins gloating about recruiting him into the League.
  Bakugo: Shut the fuck up! Get to the goddamn point already! Or do you just like hearing yourself talk!? And don’t forget that your boss said I can’t be killed or permanently harmed! From what I’m hearing, you’re bitching because you all want to cause some trouble and you want me to join you! Well guess what!? It ain’t gonna happen! You complain about suffering?! Deku was diagnosed as Quirkless and was bullied for it! I don’t see him here! And every fucking day, he kept himself under control, like a time bomb constantly resetting the clock! He could’ve snapped at any damn time and butchered everyone, but he fucking didn’t! Why? Because he has something you all don’t: integrity and compassion. Yes, society isn’t perfect, but it’s the best we have! You all wanna just tear it down just to see the ashes fly! You won’t ever get me to change my views! I won’t give in to whatever temptations you have to offer! Not even Hellfire Katsudon!
• Token Good Teammate: Mera is one of the few HPSC officials who still has a functioning moral compass, using his position to secretly leak information on the Commission's nefarious plans.
• The Worm That Walks: Thanks to his quirk making him a sentient mass of viral matter in the shape of a human, each and every one of Izuku's cells are sentient, allowing him to No-Sell Nouziri Airi's touch-based Brainwashing Quirk since her Quirk counts his cells as individual people.
• You Remind Me of X: Izuku ends up reminding All Might of All for One with his "The Reason You Suck" Speech to Todoroki in their Sports Festival match.

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