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The first time his quirk activated, it was an accident. He was 6 at the time and even though the doctors had ran all sorts of tests, nobody could determine what his quirk was or if he even had one. That meant it was probably some dumb minor quirk that didn’t stand out, like seeing the colour blue better in the dark or something like that. Nothing he could use to become a hero…
Which is exactly why Midoriya freaked out when his hands suddenly exploded after a quarrel with Kacchan. Apparently he had somehow ingested some of Katsuki’s DNA one way or another? Could’ve been saliva, or maybe blood? It had been a nasty fight for a pair of 6 year olds… Well, Bakugou basically beat him up, but still. That part was quickly overshadowed by the pure joy of finally having discovered his quirk.
It allowed Izuku to use the quirks of others, but only if he had a part of their DNA inside him and only for the duration that it was inside of him. The doctors said something about the temporary transfer of one’s quirk factor or something like that. So let’s say he ingested some DNA, it would allow him to use their quirk as long as he was still digesting whatever he swallowed. It was kinda weird and nasty to think about the details for too long and it tended to freak others out a bit, but in the end it was still a very useful quirk! One that could be used to become a hero!
He didn’t understand why his mom had been so distraught at the news. She’d made a face of pure horror and disgust and Izuku didn’t know why. Later on, he’d learn that he inherited part of his quirk from his father, who left their family when he was still young. Too young to even remember what his face looked like, let alone his personality or any characteristics. Midoriya knew it was a sensitive topic for Inko to talk about, so he never brought it up again after she explained that to him.
Kacchan initially thought it was weird and didn’t want anyone else using his awesome quirk. He came around once they realised that twice the quirk meant twice the explosions, twice the destruction. Yeah, they really wreaked some havoc in elementary school… No wonder their teachers were always pissed at them whenever Izuku used his quirk at school…
But those days were behind them now and soon enough they would be applying to high school. High school! Can you believe it?! Izuku’s hand trembled as he shakily wrote UA down as his first choice. He wanted to join the hero course with Kacchan and finally become what they always dreamed of being! The entrance exam was tough though… He’d need to prepare by gathering various samples so he’d have a selection of quirks to choose from when the moment came… But who should he ask..? Would they even be willing to help him out..?
“You’re mumbling again, nerd,” Katsuki stated, now standing next to Izuku’s desk. “School has ended already if you didn’t notice.”
It was then that Midoriya saw the classroom was empty besides the two of them. Huh, he hadn’t heard the bell ring at all… Was he really so deep in thought? It wouldn’t be the first time but still…
“I’m going to the arcade with dumb and dumber over there so you’re gonna have to walk home alone,” Katsuki added. “Also, I thought I was your only damn quirk partner? What other useless extras do you think you’re gonna ask, hah?! Don’t think my quirk is enough to pass or what is it?!”
“T-that’s not it Kacchan, I-I swear!” Izuku stammered.
“Tch, that’s what I thought,” Bakugou grinned. “Anyway, see you tomorrow nerd.”
With that the ash blonde left the room, leaving Izuku alone to stuff his things inside his bag and walk home. On his way, he continued to think about the possibilities of his quirk and the UA entrance exam. Combining quirks was something he could do, but it took a lot out of him, so he had to be careful with that. Besides, Kacchan did have a point… Explosion was a really powerful and flashy quirk, so chances were high he could pass with that one alone.
But would UA allow someone like him in when they learned about his quirk..? He was really dependent on others, after all. And Share With One could technically be classified as a blood quirk even though the DNA transfer didn’t have to occur through a blood transfer, which are mostly seen as villainous quirks… There were enough kids in his middle school that were scared of him because of the mechanics of his quirk alone. Izuku groaned. Having a villainous quirk sucked! But then again, it was better than having no quirk at all…
He was so lost in thought again that he barely noticed the loud noise behind him, freezing up in shock as slime suddenly engulfed him. It was a villain. He was being attacked by a villain! Come on Izuku, think! He was trying to pry open his mouth, to suffocate him. Was he going to die?! Oh god, oh god, oh god..! Don’t panic, keep your cool, think! Just think! You can get out of this Izuku!
This villain is made of sludge, no compact body visible so physical attacks probably wouldn’t do much. Did he still have a quirk in his system he could use? When was the last time he sparred with Kacchan? Damnit! He couldn’t think straight! Things blended together in his mind as pure terror took over. He couldn’t breathe! He was suffocating! Someone..! Please, anyone..! He… He needed help… Please… Some...one…
Just as his vision began to fade, he saw someone coming towards him in the distant. He heard a loud, booming voice, but couldn’t comprehend what it was saying. After a while he regained his senses, waking up to a face he never dreamed of seeing in real life.
“A-All Might?!” he yelped, his eyes shooting open at the sight of his childhood hero.
“Are you alright young man?” the hero asked. “That villain had quite the hold on you! Don’t worry, I have him firmly secured right here!”
He showed the green head the two bottles at his side that were filled up with the slimy substance that attacked Izuku just a minute ago, as a way to reassure the kid that everything was fine.
“I-I.. Oh my god- I-I mean, your All Might- You’re my hero! Thank you so much for saving me!” Izuku exclaimed, bowing down to show his gratitude before he started ruffling through his bag for his notebook. “Oh, uhm, c-could you maybe, uhm, a-an autograph-”
“Already took care of it, my boy!” the hero stated, handing him the notebook he was looking for. Huh, it must’ve fallen out when he was attacked or something… Oh god, did that mean All Might saw his hero analysis?! No, no, no, no, no, no… What if he thought Izuku was some creepy fanboy?! Well, he was a fanboy, but he wasn’t creepy! Unlike what some people tended to say behind his back…
“I should get this guy to the police station now. Have a good day, citizen!” All Might smiled as he waved Izuku off before jumping away. Woah… He leaped so high! Izuku stared in amazement as the wind ruffled his hair. After that he let out a squeal he’d barely been able to contain. Oh my god! He met All Might! THE ALL MIGHT! AAAAAAAAAHH! This was officially the best day of his life!
And his day was only getting better because, by some miracle, right before his eyes dangled a glinstering blonde hair. It was slowly dwindling down, reflecting some of the sunlight that was cast upon it, making it seem all the more godly. That was… All Might’s hair...THAT WAS ONE OF ALL MIGHT'S HAIRS! Izuku could feel himself start hyperventilation as he snacthed it out of the air, squealing even louder than before. God, he must look insane to anyone who was watching him right now...
Well, those onlookers had no idea what kind of treasure just fell out of the sky! One of All Might’s hairs! It had value on its own, just because it belonged to the number one hero. Izuku was sure that if he sold it online, some weird obsessive fans would give good money for it. But no, this was more valuable than anything money could ever buy. At least to Izuku. At least to his quirk.
All Might never truly disclosed what his quirk was to the public. He’d always been pretty vague about it, but Midoriya knew it had to be some kind of strength enhancer. It couldn’t possibly be anything else, not when analysing his fighting style and muscular build. So to have this hair… This DNA, this quirk factor, right here, in the palm of his hand… It held the same power as that excessive strength quirk that everyone loved and admired…
Alternatively, the best quirk in the whole damn world.
And it was now in his possession.
Yep, Izuku was ready to freak out again. Okay, deep breaths, calm down, you got this. Just… don’t lose the hair at any cost! Luckily he always had small plastic bags and tubes in his bag to carry quirk samples around so he could seal it off and secure it in his bag. He put it on his desk when he came home, instantly texting Kacchan to tell him about this miracle. He ranted on and on in their chat, spamming his friend’s inbox with thousands of long messages he’d probably never even properly read.
Nonetheless, Katsuki called Izuku only a few minutes after, screaming and shouting, demanding evidence and stating that he was coming over right fucking now. He did come over, abandoning his other friends at the arcade, and freaked out together with Izuku. Ah yes, Kacchan had always been just as much of a fanboy as Izuku was, he just hid it better.
“What the hell are you waiting for? Let’s try it out!”
“Are you crazy?! I only have one shot at this! I can’t just waste it!” Izuku frowned. “I want to use it for something special, not just to show off.”
“Hmph… So you’re keeping it until the entrance exam then?” Katsuki asked, leaning back in Midoriya’s desk chair as the green head fell over on his bed.
“I don’t know…” he whined. “I just don’t want to throw this away, you know? Gotta make it worth it!”
“Tch, you’re such a nerd,” Katsuki scoffed, yet still smiling. “What would All Might think if he knew you’re using his power for your own selfish reasons, hah?”
“Oh my god, I haven’t thought about that! What if he hates me Kacchan? What if he doesn’t want me using his quirk?!” Izuku yelped, instantly sitting straight up again. “I normally always ask for permission, you know that! Using it without him knowing would be so rude!”
“Oi, calm the fuck down, I’m sure it’s gonna be fine,” Bakugou said. “Besides, nobody needs to know it’s All Might’s quirk, right? Could be any extras’ random strength quirk. Not like those are rare or something.”
“...I guess that’s true,” Izuku sighed. “But I’ll still know it’s his, and so will you.”
“That’s our little secret then,” Bakugou grinned. “Come on nerd, be glad you even got the chance to use All Might’s quirk! Even if it’s only once! You know how many people wished they’d have that opportunity? You’ll fucking crush the entrance exam if you use it, for sure.”
“You’re right about that,” Midoriya hummed, smiling a little. “Yeah, you know what? Maybe I will use it to pass the UA entrance exam. Who’s gonna stop me huh?”
“That’s the spirit!”
And so here he was, standing in front of the gates of UA high with Kacchan by his side, his hands trembling as they held onto the small plastic bag with All Might’s hair in it. To say Midoriya was nervous was an understatement. It made him jittery and reduced him to a mumbling mess, much to Bakugou’s annoyance. Why was he even putting in the effort of bringing this idiot to the auditorium in the first place? At this rate there was no way this loser was making it into UA!
“Oi, stop it. You’re making a fool of yourself and of me,” Katsuki hissed as he pushed the green head down in a seat, huffing as he sat down next to him. “Seriously, you’re such a fucking worryward… I don’t know why I keep putting up with your bullshit.”
“You’re so mean Kacchan,” Izuku whined.
“And you’re annoying,” the ash blonde countered.
Ah yes, they truly had a wonderful friendship, hadn’t they? Present Mic soon began explaining the entrance exam as Izuku kept fiddling with the plastic bag.
He should eat it in time so the hair would definitely be in his stomach by the time the test actually started. You see, it takes a person around 36 hours to digest something, which would also be the limit of his quirk. But it takes like 20 minutes for something to go down into the stomach after you’ve swallowed it, and his quirk only started working after the DNA reaches his stomach. That’s where his body can absorb the quirk factor that’s embedded within it so he’s capable of using it.
“Just eat it and get it over with nerd, not like it’s gonna wear off before the test ends at this point,” Katsuki whispered.
“But I want to use it afterwards too, you know, to feel cool and stuff…” Izuku mumbled, earning an eye roll from his friend. They were quickly called out on their whispering by some other kid attending the info session and went back to silence as they listened to the instructions and point distribution system.
“It’s too bad we won’t be in the same area… I really wanted to fight with you Kacchan!”
“Tch, just worry about your own damn exam. I’m gonna pass with or without you, got it?”
“Of course! Wait for me afterwards, okay? I wanna discuss our exams on our way home,”I Izuku smiled, making Katsuki groan.
“Alright, fine, just fuck off and get ready dumbass.”
Izuku knew that was Kacchan’s way of encouraging him, as weird as it sounded, so he simply nodded and waved him off as he ran towards ground beta, where his exam would be held. He swallowed the hair on the way, coughing and feeling icky afterwards. Hair was one of his least favourite ways to transfer quirk factors. I mean, who would like to have hair in their mouth? Let alone swallow it? Ew!
No, blood or saliva were practically tasteless and if he cleared his head and didn’t think about what the hell he was actually drinking and maybe mix it in with some water or something, it actually went down pretty easy. Others still thought it was disgusting but it’s not like he had other options. This was the quirk he was born with and he was gonna make the most of it goddamnit!
What worried him though was that he didn’t really feel anything after half an hour had passed and it was almost time for the giant gates in front of him to open. He hadn’t felt a spark of energy, didn’t feel like his body had absorbed… anything , to be honest… His body didn’t gain any muscle mass, so no physical changes either… Was he wrong..? Was it not All Might’s hair he just swallowed..?
“ALRIGHT YOU HERO HOPEFULS! TIME TO GET THIS PARTY STARTED!”
Izuku was startled out of thought as Present Mic started shouting, quickly taking a big chug of his water bottle so he’d at least have Kacchan’s quirk if All Might’s was a dud and ran in with the other contestants. Water went down faster than solid substances so he was able to use Explosion within a few minutes. It put him behind the other candidates, but hopefully he would still be able to rack up enough points to pass. He had to, failure was not an option. No, if Kacchan found out he lost while using his quirk, he’ll murder him… Izuku felt shivers run down his spine at the thought alone.
Right after, a loud rumble shook the ground and a giant robot appeared from behind the skyscrapers. That must be the zero pointer… Izuku never expected it to be so big! It was only logical everyone was running the opposite direction, trying to get as far away from it as possible. Midoriya wanted to get going too, until he saw a girl stuck in the rubble on the road up ahead. Izuku’s eyes widened, his feet frozen in place. That thing was going to crush her!
It was that moment he felt a spark. Like a switch that was flipped and a light that turned on. Suddenly his legs were moving. Running. Jumping. Flying. It all happened so fast! Before he realised it, he was hovering in front of the zero pointer. Power rushed through his veins and his fist connected with the cold, harsh metal. It was only when it dented, when the robot tumbled back, that Izuku realised what he was doing. It was also that moment the pain caught up with him.
Fuck!
Both his legs were broken, so was the arm he used to punch the giant zero pointer. And now he was falling back down to the ground, which was so so far below him. Damnit! Come on Izuku, think! Stay calm, come up with a plan, you can do this! He turned his body around midair, aiming his good hand at the ground. An explosion should at least cushion his fall a little, right? It would break his momentum, make the landing a little more tolerable. Yeah, okay, that was a plan. Now for the execution… He’ll only get one shot at this!
His hand started sparking up, creating bigger and bigger blasts until one larger one stood out, momentarily breaking his fall, even throwing him back up a little, before he crashed down onto the street.
“Are you okay?!”
It was a female voice, but Midoriya couldn’t pinpoint where it was coming from.
“Don’t move, okay? Somebody help him! He’s hurt!”
He blinked, his vision blurry as he saw the silhouettes of various people in the distance, some getting closer, others further away.
“Hey, come on, stay awake. Help is on the way!”
He groaned, blinking again. Only now there was only darkness. A silent black void. Just… nothing… Izuku couldn’t feel his body anymore and for a moment he thought he might’ve died. But then there was a voice. A man. He sounded so incredibly familiar, yet Izuku was sure he’d never heard that voice before.
“It’s you…” the man whispered. A hand appeared in front of him and Izuku was able to look up, following the hand up to face the man speaking to him. He has emerald green eyes, just like Izuku, and white shoulder length hair. “It’s alright, little one. I’m not here to hurt you.”
The man managed a small smile as Izuku took his hand, pulling him up on his feet. The moment he did, the world changed around them. Might invaded his vision and images flashed before his eyes. It gave him some serious whiplash, almost making him fall back onto the ground. Yet the man had a firm hold on him and the moment Izuku could get a clear view of him again, there were several others surrounding him.
“He shouldn’t be here,” one said. “It’s too dangerous.”
“He’s just a kid!”
“Are we even sure it’s him?”
“It’s him,” the man stated, still smiling at Izuku. Him? Who was he supposed to be? Who were these people? Was he hallucinating? Was this all just some creepy freaky crazy dream? He must be unconscious from the fall… Yeah, that’s it! He fainted after what happened at ground beta! That was the only logical explanation!
“What’s your name squirt?”
Izuku glanced aside, seeing a woman who kinda resembled his mom. Although her hair and eyes were darker, she emitted a similar aura. A feeling of comfort…
“Izuku Midoriya,” he answered easily, making her eyes widen. “Is something wrong? Where am I? Who are you people?”
“Nothing is wrong,” the man said, gaining his attention again. “As for the rest of your questions… You’re now within One For All.”
“One For-“ Izuku started mumbling, cutting himself off as images invaded his vision once more. Of heroes fighting a villain, of a quirk being passed down from one hand to another, of All Might. Of a monstrous villain that destroyed everything in his path, of a brother, of a father… His father. Izuku gasped, stumbling back. Suddenly the other people’s presence felt stiffening, their looming faces threatening as they reached out to him. No… No, no, no, no, no!
“It’s okay Izuku, you’re safe here,” the man told him, grabbing his hand again. He was the first… He was his brother… His uncle- “Calm down, there is no need to overthink this.”
“Overthinking?!” Izuku wheezed out. “You’re- I-I’m- All Might, he- And my dad- I can’t-“
“He’s right, you know? There is no point in freaking out,” another one said, putting his hand on Izuku’s shoulder. He kind of looked like Kacchan…
“You’re my brother’s son, my nephew,” the First started. “Your quirk factors are so similar… It almost feels nostalgic.”
“Oi, don’t go spacing out on us now. We don’t even know how the hell this kid got his hands on One For All,” the Kacchan look-alike told him.
“His quirk is similar to my brother’s, although one might call it an inferior version,” the First explained. “Where All For One permanently takes someone’s quirk factor for his own, Izuku only takes a small sample of the quirk factor without inconveniencing the original user, creating a temporary quirk transfer.”
“I’d say that’s a superior version,” Nana smirked, harshly patting Izuku on the back. “Good work kid!”
“So what? He somehow got a sample of Toshinori? We would know about that,” someone else commented.
“Does it really matter how it happened? The facts are what they are, this is what we have to work with,” Nana stated.
“Izuku,” First called out, making the boy look at him again. “I want you to find All Might after you wake up, okay? I trust in his judgement.”
“W-what do you mean..?” Izuku asked, still unsure about all of this.
“Does everyone agree with me?” First asked, completely ignoring his nephew. There were grunts and eventual nods, all of them giving in to the suggestion. “Great! Then that’s settled.”
“What’s settled? What’s going to happen? I-I don’t-“ Izuku stammered, only to get hugged by his uncle.
“We’ll meet again, I’m sure of it,” he whispered. “Stay strong, okay? You’ve got this.”
Before he could ask anymore questions, his vision blurred again and with a gasp, he shot up from what seemed to be a hospital bed.
“Holy fucking shit! Fuck! Don’t fucking scare me like that you dumbass! Who the fuck wakes up like that?!”
Izuku panted, barely registering Katsuki’s presence as he came to his senses. He was injured, the pain coming back to him now that he was awake again. Those people… That quirk… One For All. And All For One. All Might. He had to talk to All Might.
“Oi, you okay?” Bakugou frowned, snapping his fingers next to Midoriya’s face, startling the green head. “We’re in UA’s nurses office, by the way. Recovery Girl healed you up, cause what the fuck Izuku. How the hell did you manage to break both your legs and one of your arms?!”
“I… I used it,” Izuku breathed, swallowing the lump on his throat. “All Might’s quirk… It backfired on me.”
“What?” Katsuki asked. “Why? Your body always adapts to quirks instantly…”
“This one is different,” Izuku frowned, throwing the sheets off his legs. Seemed like he should be able to walk again.
“Different how? Talk to me nerd,” Kacchan demanded.
“I need to talk to All Might,” Izuku said, climbing out of bed despite Bakugou’s protests. Before any of them could make it out of the room, a tall frail man entered. Toshinori took in the scene in front of him, glancing between the two teenagers. If it weren’t for the fact he reviewed the camera footage, he wouldn’t be able to sense which one of them it was. Which one of these kids held his quirk… But he did sense it earlier, back when One For All activated inside another, when a candidate smashed one of the zero pointers…
“Ah, hello,” he smiled. “You two must be students that participated in the entrance exam, right? I’m-“
“-All Might,” Izuku said, cutting him off. Katsuki’s eyes widened in shock as he looked at the man in front of them. This wasn’t All Might! This nerd must be delusional or something! “We need to talk, it’s urgent.”
“I think you’re mistaken-“ Toshinori tried, not wanting to reveal too much when he wasn’t even sure what his motives or background were.
“I talk to the vestiges in my dream, I know about One For All,” Izuku continued, silencing Yagi once more. “And I… I think my father is All For One.”
Yep, that’s how it all started. That’s how Midoriya became All Might’s successor, how his story as a hero began. How one small coincidence changed the rest of his life…