Fanfic / Incident Zero

Incident Zero is a My Hero Academia fic by Ya Boy Guzma (AO3 link here).

All For One and All Might's fight takes place a bit earlier than in canon, and, more importantly, resulted in both of their deaths. This caused a series of ripple effects that resulted in a very different, much harsher Japan than in MHA canon. It also resulted in a dying All For One giving Izuku his quirk, telling him "it's your world now."

Now, armed with the power of one of history's greatest villains, Izuku sets out to become a true hero in a country that is rapidly losing sight of what that means. Alongside him are Tenko, his cynical, game-obsessed confidant and oldest friend, Setsuna, his prodigy cousin who enjoys teasing him to no end, and Himiko, an upbeat girl who shares his interest in hero analysis, but who might be more than she appears at first glance.

Unmarked spoilers for both the fic and the My Hero Academia manga ahead.

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Incident Zero contains examples of the following:

• Adaptation Name Change: Bakugou's hero name here is Ground Zero, and Shouto's vigilante name is Juhyo.
• Adaptation Relationship Overhaul:
  • In canon, Izuku and Tenko were enemies. Here, since Izuku was the one to find Tenko after the death of his family, they have become best friends.
  • In canon, the Kamui Woods had at worst a professional relationship with Mt Lady and Death Arms and at best was rumoured to be in a relationship with the former. Here, Kamui Woods is a lot more hostile with Mt Lady and Death Arms since the latter two are commission dogs who interfered in an incident Kamui had under control and caused a lot of damage as a result while Kamui is truer to All Might's vision of what a hero should be.
  • In canon, Shouto has no idea that his oldest brother Touya is even alive, and when the truth finally does come out Touya/Dabi has no qualms about trying to kill him to hurt Endeavor. Here, Shouto runs away from home and Touya takes him under his wing.
• Adaptational Heroism:
  • Tenko. In canon, he's groomed by All For One to become his lieutenant. Here, his quirk awakens later and he is taken in by Izuku and Inko, leading him to become a hero.
  • Toga. While she still suffers bloodlust, she seems to have it better managed here thanks to Stain's influence and having access to blood from blood banks. While she's an active disciple of Stain here, even helping him track down and case targets for assassination, she also in her own words has never killed a hero. After meeting Izuku, she becomes inspired to attend UA and at least try to be a 'true hero.'
  • Stain himself as well, though this is less because he's changed his methods and more because heroism as a profession is far more corrupt than in My Hero Academia canon, which gives him far more justification to do what he's doing. Giving him humanizing interactions with Spinner and Toga doesn't hurt, either.
  • Giran is a broker who supplied only villains in canon. Here, he supplies vigilantes trying to do good for society as well.
• Adaptational Superpower Change:
  • Izuku is given All For One by its dying owner when he is eight years old, as opposed to being given One For All by All Might just before high school like in canon.
  • Inko in canon has Attraction of Small Things. Here, she gives it to Izuku to cover for any holes in his cover story that his quirk is simply Aerokinesis.
  • Tenko has One For All because All Might tricked him into drinking his DNA on the day of Incident Zero.
• Adaptational Villainy:
  • The Hero Commission as a whole, and a good chunk of heroes working directly for them. YMMV on how clean their hands are in canon, but here they respond to rising levels of crime following All Might's death by bringing down an iron grip on society and turning pro heroes into their own domestic army.
  • Slugger. In canon, he's a one-off background character who fails to save Bakugou from the Sludge villain. Here, he's a bigot and a sadist who savagely beats Toga for her blood-drinking quirk before getting killed by Stain.
  • Snatch. Yet another one-shot character from canon whose main claim to fame is asking Dabi if he ever stopped to think about his victims' families before getting roasted. Here, he's on the payroll of a drug kingpin.
  • Mt Lady and Death Arms are Hero Commission lackeys doing a lot of harm following their orders where in canon, though they can be selfish glory-seekers, mostly did their jobs as heroes properly.
  • Kesagiri Man was a hero who fought against the Shie Hassakai Yakuza in canon. Here, he's on the Shie Hassakai's payroll.
• Age Lift: Tenko and Toga are a couple years younger than in canon, and Dabi is a couple years older. Downplayed for Dabi, since his official age had not been confirmed when the fic was first being written.
• Anti-Hero:
  • Tenko is cynical, sharp-tongued, has a temper if his buttons are pushed, mostly only maintains a "no killing" rule for Izuku's sake, and finds it hard to completely disagree with the Hero Killer. He's also Izuku's closest and most loyal friend and is trying to follow his lead and become a true hero.
  • Bakugou still bullied Izuku in school and has a temper and ego the size of Japan. However, he's also got a strong sense of justice that manages to throw Stain for a loop, is willing to break the law to try to save civilians, and wastes no time in calling out the Hero Commission when their restrictions and political maneuvering get people hurt. When presented with the existence of the Meta Liberation Army, who practice an actual supremacist ideology, he's disturbed. He also has slightly more justification for being angry at Izuku, if not for bullying him, compared to canon since he clocked onto the fact that Izuku (accidentally) stole his friends' quirks before anyone else, even Izuku himself, did.
  • Instead of being a hero student, Shouto/Juhyo is a vigilante. However, his entire motivation revolves around bringing down and exposing his powerful abusive father in hopes that it will help true heroes begin to flourish again. He also readily puts himself between Dabi and Uraraka when his brother is ready to kill her for knowing too much. He's contrasted with the other members of Dabi's crew, who lean more towards the Anti-Villain side of things.
  • Dabi himself is either a nominal hero or an outright Anti-Villain. He is ready to do anything to take his revenge on Endeavor, including being ready to kill Uraraka for stumbling onto their plans until Shouto forces him to stop and giving Shouto false promises that he won't kill Endeavor when everything's over to keep his brother on his side.
• Arrested for Heroism:
  • A large part of the Hero Commission's plan to overhaul the hero system in Japan includes much harsher punishments for vigilantes.
  • Happens to Bakugou after he takes down a villain that Kamui Woods, Death Arms, and Mt Lady are too busy fighting amongst themselves to stop. Luckily for him, Endeavor recognizes his potential and bails him out.
• Blatant Lies: When All for One convinces Izuku to press Himiko on her activities due to his suspicion that she was involved in an attack on a prisoner transport, Himiko lies and claims she was involved in a fight club. It succeeds in fooling Izuku and even All for One.
• Bothering by the Book: After All Might's death, the hero commission brings all hero schools directly under their control, as well as stripping all non-hero curricula like business and support courses. They do something similar with hero agencies, bringing them directly under their command to deploy as they see fit unless they can secure private funding. Nedzu's response? Registering UA High School as a private hero agency headed by himself under which the staff are workers and the students are apprentices or support staff, ensuring that at least a little of All Might's brand of heroism remains alive.
• Brainwashed and Crazy: Hawks has been subjected to constant brainwashing for two years to turn him into the perfect weapon for the Hero Commission. Shinsou is horrified that his own mother did this to one of the few heroes on the commission's payroll who tried to live up to All Might's ideals.
• Cliffhanger:
  • Chapter 43 ends with Izuku meeting the vestige of All for One for the first time.
  • Chapter 47 ends with the leaders of the Meta Liberation Army preparing for war.
• Crapsack World: After All Might's death, Japan went to hell. On one end, villains, yakuza groups, and other criminal organisations became emboldened in the aftermath of All Might's death. On the other end, the Hero Commission which was supposed to keep things together deliberately made things worse by making it almost impossible for independent heroes to exist at the exact time Japan needed as many heroes as possible to deal with the skyrocketing crime rates.
• Combo Platter Powers:
  • Izuku has all the quirks of All For One stored in his body, plus a few more he's accidentally stolen since copying it. However, he's only able to use a very small subsection of them thanks to his body having a limited but growing ability to use them.
  • After Izuku gives her a finger elongation quirk, Setsuna also qualifies.
• Commonality Connection: All for One respects Izuku's desire to be on top of the Hero World, saying it reminds himself of his desire to be superior to everyone else.
• Corporate-Sponsored Superhero: The only remaining option besides retirement or vigilantism for heroes who don't want to be under the direct control of the Hero Commission is to seek independent funding from other sources such as corporations.
• Death by Adaptation:
  • Lots of people were killed in the fight between All Might and All For One. These include All Might, All For One, Hisashi Midoriya, Toga's parents, and Kyouka's father.
  • Stain and Spinner kill Mt Lady as they have, not unreasonably, judged her as a terrible hero and a horrible person.
  • Later, Kaminari gets killed by a mind-controlled Hawks and the Hero Commission for illegally using his quirk to stop some criminals.
  • Muscular is killed by Re-Destro during their meeting.
• Deep Cover Agent: Eraserhead is this for Nedzu inside the Meta Liberation Army instead of teaching at UA. So far, he's gotten in deep enough to openly eavesdrop on the leaders of the organization.
• Defector from Decadence: Shinsou. His mother is a high-ranking member of the Hero Commission, and he himself is being trained by them. When he sees what she's done to Hawks, he runs away in hopes of becoming a whistleblower.
• Despotism Justifies the Means: The general attitude the Hero Commission adopted after All Might's death.
• Didn't See That Coming: When All for One gave his Quirk to Izuku, he was expecting to take over Izuku's body. But Izuku being Quirkless messed with his plan and his Quirk became Izuku's instead of remaining under the original wielder's control.
• Disability Immunity: Izuku being Quirkless made it possible for him to resist being taken over by All for One after the latter forced his Quirk on him since Izuku had no Quirk to fight and take over.
• Disappointed by the Motive: Class 1-A finds Mustard's motivations to attack them, being embarrassed by his aunt's, Midnight's, entire theme as a hero, to be completely underwhelming and Shoji suggests he's really just using it as an excuse for his own despicable nature.
• Do Not Adjust Your Set: With the huge media coverage on the USJ incident, Dabi hijacks the broadcast to reveal Endeavor's Domestic Abuse, realising there was no better opportunity to ruin his father.
• Dramatic Irony: The leadership of the Meta Liberation Army knows about the Shie Hassakai's goal to get rid of quirks, but believe the latter has no hope of achieving it. What they don't know is that the yakuza has Eri, and that they actually do have a chance. Overhaul is more than pleased when he realises they don't know about Eri.
• Enemy Mine: Having a mutual enemy in the Shie Hassakai, Stain's group and Nighteye's agency agree to a temporary truce to take down some of their soldiers, one of their highest lieutenants, and a pro-hero in their pockets. It ends after Stain and Spinner kill one of the yakuza since Nighteye and his sidekicks cannot let that slide. Stain is fine with that since it helps prove Nighteye and his sidekicks are some of the few actually good heroes left.
• Even Evil Has Standards: By the end of their meeting, Re-Destro is repulsed by Muscular who wants violence for its own sake instead of using violence as a tool for their goals.
• Everyone Has Standards: As uncomfortable as he is with murder, Shouto does get that sometimes, that is the only justice available in the post-All Might world. This is why he accepts Snatch being killed since he's a corrupt hero. Where he draws the line is in hurting innocent people in pursuit of getting at the bad people, since that makes him and Dabi just like Endeavour.
• Evil Mentor: All for One is the greatest villain and yet teaches Izuku how to use his Quirk and gives advice in general.
• Famed In-Story:
  • Kyoka Jirou is famous as a singer, writing songs that represent the negative moods Japan is feeling after Incident Zero.
  • Bakugou Katsuki is famous as the boy charged with vigilantism who is given a lifeline by Endeavour. He becomes even more notorious after a live on-field interview with Curious spreads like wildfire where people can see his negative traits and yet find validity in his rants on the failures of the Hero Commission.
• Fantastic Ableism: Quirk-based discrimination has gotten worse after Incident Zero. Quirkless abuse has always been common, but society as a whole are treating those with significant mutations even worse than before, and even so-called heroes openly treat people with quirks considered villainous with disdain.
• For Want Of A Nail:
  • The UA Entrance Exams are completely reworked by the time Izuku and his friends apply to them. With the significant decrease in funding, they can no longer afford to do large-scale battles against robots.
  • Because it's Dr Garaki leading the League of Villains during the USJ incident, the planning involved is more meticulous and thorough, making the battles for the teachers and students far harder than canon was.
  • All Might encounters Nana's family on the day of Incident Zero instead of never meeting them before he meets Shigaraki in canon. Because of this, he has the opportunity to pass One for All to Tenko.
  • Villainy rising after All Might's death has led to prison overcrowding, which necessitated prisoner transports to make sure security can be maintained. Lady Nagant being one such transported prisoner gives Stain's crew the opportunity to break her out and she joins them.
• Foreshadowing: During the Quirk Assessment tests, Monoma tried copying Tenko's Decay but couldn't get it to work. That's because he didn't copy Decay. He copied One for All.
• Friendly Enemy: Miruko and Kendo Rappa may be on opposite sides of the law, but it does not stop them from respecting each other.
• Freudian Excuse Is No Excuse: Katsuki is unsympathetic to Dabi's abuse at Endeavor's hands as his justification for villainy, pointing out that many other kids suffered abuse without becoming murderers like Dabi. Burnin agrees with his sentiments but points out that the general public won't since Endeavor is both the current Number 1 hero and has existing reputation problems.
• Godzilla Threshold: Discussed. The threat of the Meta Liberation Army is so great that Nedzu is considering sending his students to fight them, but he has not committed to this action just yet.
• Good Is Not Nice: After a lifetime of being looked down on for a quirk that only lets him copy others, Monoma wastes no time in forming a very negative opinion of Toga and Izuku (who have their own reasons for not wanting people to know their full quirks without being told) when they are hesitant to let him copy their quirks. It's somewhat understandable given his experiences, but as Setsuna points out, the fact that nobody's obligated to let him use them for anything, even if there's no risk to them, means his reaction is out of line. He also copies Tenko's quirk without asking and, when he fails to get it to activate and gets some light snark from Tenko for it, viciously mocks Izuku and his friends.
• Good Is Not Soft: Tenko may be on the side of the heroes because of Izuku, but he will not hesitate to kill if that is what it takes to save his friends. Which is why he decides to kill the Nomu during the USJ attack as he can't see any other option.
• Grey-and-Black Morality: The conflict between Endeavour and the Meta Liberation Army is one between a man who means well and does some good but is also responsible for a lot of bad things, and a group that's hell-bent on liberation of meta abilities no matter the cost, even if that cost is tearing society apart.
• Grey-and-Gray Morality: The conflict between Endeavour and Dabi is one between two different men who mean well but have or are willing to cause a lot of harm in pursuit of their goals.
• He Who Fights Monsters: Dabi's willingness to cross the line to make Endeavour pay for his crimes worries Shouto, who calls him out for being like Endeavour when he almost murders Ochako.
• Hero Insurance: Defied thanks to being deliberately rolled back by the Hero Commission, forcing citizens using their quirks and private heroes to pay for any damages out-of-pocket.
• Hero with Bad Publicity:
  • Endeavour has a bad reputation with the general populace for, among other things, excessive collateral damage and his role in making Japan worse by supporting the laws that made being a proper hero harder. It gets worse after Dabi takes advantage of the media attention on the USJ incident to reveal Endeavor's Domestic Abuse. Especially with Shouto talking about the abuse. If it was just Dabi, the validity of his allegations would have been questionable at best, but Shouto backing up the claims leaves little room for doubt.
  • After the USJ Incident and the reveal of Endeavour's abuse, the entirety of Hero Society lost what little faith the public had in it. UA, and all Heroes, are criticised and some protests are violent. The HPSC responding violently against the protest does not help their case and only pours more fuel on an already raging fire.
• I Have Many Names: Dr. Garaki has a lot of different aliases he used throughout his life.
• In Spite of a Nail:
  • In spite of every other divergence, the League of Villains still attack the USJ while Class 1-A is there, though it's to get Izuku, not All Might.
  • In spite of being in the middle of Incident Zero, Kotaro still attacks his son out of fear after Tenko's Quirk awakens.
  • In spite of so many different circumstances, The Meta Liberation Army still gets to count Hawks as one of theirs. The only difference is that Hawks has been brainwashed by them instead of being a spy on them like in canon.
• Internal Reveal:
  • Setsuna learns the truth about Izuku's Quirk when she sees him take Inko's Quirk, while Himiko learns about it during the USJ Incident.
  • Izuku is told the true name of his Quirk during the USJ incident.
  • Burnin and Bakugou find out the CEO of Detnerat is part of the Meta Liberation Army in Chapter 53.
• Jerkass Has a Point: After his interview with Curious, most people find Bakugou to be a feral little boy, but agree with his points that the Hero Commission has failed Japan and isn't doing much to actually protect people. It's lampshaded by others that they shouldn't like him for his negative traits, but they can't help but respect that he's trying to make a difference.
• Knight Templar: The Hero Commission keep telling themselves they are in the right, no matter how many atrocities they commit, no matter how misfocused they are on vigilantes than criminals and villains, no matter how badly they broke society even further in the aftermath of Incident Zero.
• Living MacGuffin: Izuku is this for both Overhaul and All For One's disciples, though so far Overhaul doesn't know his identity. For Overhaul, it's because he knows there's someone capable of fully removing quirks from people, which furthers his goal to purge them from society. For All For One's disciples, it's because they intend to coerce him into becoming a crime lord and the new 'apex predator' of quirk society to enforce order.
• "Not So Different" Remark:
  • Stain tells Nighteye that they are both men who saw the world's sorry state and tried to do something about it. Nighteye retorts that he never killed anyone to do it.
  • All for One tells Izuku they are alike because they want to change the world.
• Oh, Crap!: Burnin and Bakugou are shocked to learn the CEO of Detnerat, their boss' biggest sponsor, is part of the Meta Liberation Army.
• Power Misidentification: When Izuku first manifests Air Force, one of the many Quirks of All for One, he thought that was all he had. It is not until later he learns that his power is so much more than just Air Force, but he keeps the ruse up, only trusting his closest friends and family with the truth of his power.
• Pragmatic Villainy: All for One may be one of society's greatest evils in life, but he helps Izuku out when he's in danger as his own survival is dependent on Izuku's now that he's a vestige stuck inside him.
• Related in the Adaptation:
  • Setsuna Tokage is Izuku's cousin here. Her uncle is also Rapt Tokage from the Vigilantes spinoff manga (in the original mangas, Setsuna and Rapt's last names are pronounced the same but spelled differently in Japanese).
  • Kodai Yui is Mr Compress' estranged daughter here.
  • Mustard is Midnight's nephew, a fact Mustard and the other members of the League of Villains exploits during the USJ attack.
• The Reveal:
  • Chapter 42 reveals Tenko has One for All.
  • Chapter 47 reveals Hitoshi's mother Haruga is a high-ranking Meta Liberation Army operative, and influencing the Hero Commission to be harsh on vigilantes and convincing them taking over Hawks' mind is a good thing is all part of the plan for their vision of a perfect society.
• Secret-Keeper: Bakugou learns about Endeavour's first son Touya. Endeavour warns him to never mention Touya in public.
• Screw the Rules, I Have Money!: Because of the Hero Commission rolling back Hero Insurance and funding for independent heroes, the financially distressed heroes have become morally compromised and are more open to taking bribes from people with enough money.
• Shipper on Deck: All for One's vestige tells Izuku that Himiko's a keeper.
• Shout-Out: All for One says "I love democracy" as a reference to Star Wars.
• Skewed Priorities: The Hero Commission are far more concerned with stomping out vigilantism than they are with dealing with actual criminal organisations.
• Spirit Advisor: Though he gives dangerous opinions, All For One's vestige can be helpful by giving useful advice to Izuku on certain people and situations as well as how to use his bequeathed quirk. He even helps out a little against his former top lieutenants when said lieutenants try to take Izuku even as he tries to get him to accept Dr. Garaki's offer.
• Soul Fragment: Part or all of All For One's consciousness still exists within his quirk. So far, Izuku's thoroughly noticed it but attributed any thoughts from it to his own subconscious.
• Vetinari Job Security: Deconstructed. The stability of society was too dependent on All Might being around. His death resulted in a gaping hole no one could fill and everything just keeps falling apart.
• Villain Has a Point: As much as Izuku hates it, All for One often brings up good and compelling points that he cannot afford to simply dismiss.
• Villain Respect: All for One respects Izuku's drive, saying it helped him in his attempts to master the All for One quirk.
• Well-Intentioned Extremist: Endeavor supported changing the laws that forced heroes to either become commission lackeys or sell-outs because he genuinely believed it would make them stronger and better able to deal with the rising crime rates. After seeing the actual effects though, he comes to regret it.
• Wham Episode:
  • Chapter 41 has a lot of major developments. Izuku rejects Dr. Garaki's offer, manages to steal Kurogiri's Warp Gate quirk, and Dr. Garaki decides to kill Izuku for rejecting becoming All for One's replacement.
  • Chapter 42 has one big development. Tenko had One for All all this time! Neither he nor anyone else knew about it.
• Xanatos Gambit: So far, this is how the MLA seems to operate. They encouraged the Hero Commission to become more totalitarian in the hopes that it would stir up public opinion against them, eventually priming the populace for a full revolution. In the meantime, they can use their own ties to the Commission to acquire more resources and information. They also intend to encourage Endeavor and Bakugou to rebel against the Commission's tight restrictions, so that they can hold them up as either shining examples of the effectiveness of free quirk use if they succeed, or as martyrs if they fail.
• Your Approval Fills Me with Shame:
  • Downplayed. Nighteye finds it difficult to accept praise from the Hero Killer but does accept them for what they are.
  • Izuku is uneasy to receive praise from the vestige of All for One.

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