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POWER!! : An origin story

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"I can't believe All Might is asking me to be his successor! This is amazing, but am I truly worthy, I have to call Mirio, no I have to call Aizawa-sensei!"

All Might sweat dropped at his hopeful successor. Probably shoulda told him this was a secret.

"Uh, Midoriya my boy, I'm sorry but you can't tell anyone what I am offering you."

Izuku stopped his muttering at his hero's words. Not being able to tell his best friend and adoptive father was, in his opinion, a deal breaker. He couldn't accept something as big as All Might's quirk without at least asking what they thought. With everything they've done for him it was the least he could do.

Looking to skinny might Izuku braced himself for the hero's reply.

"All Might sir, as honored as I am that you would offer me the opportunity to be your successor, I can't in good conscience accept…I'm sorry."

All Might was speechless to hear his ideal successor rejecting his offer. It was a blow to the gut seeing as he was searching for so long for him.

"Young Midoriya, why you would reject an offer such as this."

Izuku took a deep breath, "I just feel that it would be wrong of me to accept such a power without telling Aizawa, the man who willingly adopted me after only knowing me for a year. And Mirio, he's been by my side for almost 7, no 8 years. Not telling him would be a betrayal to our friendship. Not to mention even if I didn't tell Mirio and the others about OFA they would still suspect something was up since my quirk is pyrokinesis. It's just...I know this is a lot All Might sir, but it's the truth."

Bowing to the older man, Izuku began his trek home leaving behind a speechless All Might. Toshinori Yagi had no idea how to respond to what Izuku had told him. Once he realized he was about to let the perfect successor slip through his fingers he finally got himself together.

"Wait, young Midoriya, please wait!"

Izuku was a few feet away when he heard All Might yell out for him. Turning he saw his hero reaching out for him with a small smile.

"Izuku Midoriya, you truly have the heart of a hero! Become my successor and I will allow you to tell those you deem trustworthy!" he smiled.

Tears ran down Izuku's face as he listened to All Might's words, "I accept, All Might!"

"Just what I wanted to hear! Now than when should I expect you to tell Aizawa and the others?" he asked.

Izuku tapped his chin in thought. The sooner the better would be preferable. However, he knew Aizawa and the others were rather busy given it was the middle of the school year and they were crammed with their exams and internships. Then as if a light bulb lit up in his head Izuku told All Might his plan.

"Today is Friday, All-

"Please call me Yagi when I'm like this" he smiled.

"Oh yeah sure, well anyways since today is Friday, Mirio and the others will be coming over to my place for Katsudon which makes it the perfect time to tell them!"

All Might beamed at his successor, "Ah getting things done as soon as you can eh my boy! I like how you think. Well let's go then, we have some news to relay to everyone."

And so, the two went on their way to Izuku's house.

To say Aizawa was shocked to see Toshinori Yagi on his doorsteps with his adopted son would be putting it lightly. He was flabbergasted, bewildered, mind boggled any other word which conveyed confusion. Deep down he had a bad feeling about this.

"Uh, All Might, can I ask why you're with Izuku?"

Unfortunately, before the hero could answer a hyper teen popped up behind Aizawa eyes wide at the sight of the number one hero.

"All Might! Oh my gosh it's All Might! Mirio, Tamaki, come here Izu-kun's with All Might!" Nejire yelled.

Izuku's lip twitched at his girlfriend's tactfulness.

"Oh-ho-ho look at our little Izu-bro making friends with the number one hero of japan! What an honor to be in your presence sir!" Mirio said popping up from the ground.

"Bahahaha, thank you!" All Might bellowed in surprise at a boy appearing from the ground.

"Holy crap, All Might" Tamaki whispered from his corner.

Aizawa finally gathering his wits, moved to the front of the rowdy teens, "so again I ask, why are you with Izuku?"

"Ahh, yes, well uh, take it away Midoriya!"

Izuku stared at his new mentor in betrayal. "Traitor", he mumbled.

"Uh, well dad…first food!"

Rolling his eyes at his son's blatant change of subject before bringing the food out.

As everyone finished serving themselves and dug in, Aizawa stared straight at the sweating hero.

"We're eating. Now spill."'

"Aizawa!" Izuku yelled.

Aizawa glared at the boy, halfheartedly.

"Right. But before I get started, I want the three of you", looking to Nejire, Mirio, and Tamaki "to swear what I reveal to you will not be repeated outside of this house."

The three teens looked to each other before shrugging and nodding to him.

"Yeah, okay, we promise, sir!" the four teens saluted.

All Might smiled at the teens spirit. "Well then, first off let me formerly introduce myself." Deflating All Might shrinks into his true form, and waves, "You all know me as All Might, my actual name is Toshinori Yagi."

The three teens fell over looking at the skinny man who now looked on the verge of death.

"AHHHHHHHH, what happened to All Might!"


"Run Izuku, we'll protect you!"

"ENOUGH!" Shota yelled turning to two teens huddled on top of Izuku, who was trying his best not to topple over, and Mirio in front of him with his arms in an X formation.

"Yagi, explain."

Sighing he goes through the story of All for one and the fight which occurred five years ago giving him the stomach injury.

"Wait, so you can only go out for three hours a day to perform heroic duties!" Nejire shouted.

"You have a transferable quirk that has been passed down through seven people!" Mirio yells.

"You were quirkless." Tamaki whispered.

"Indeed, and because of all this I have been looking for a successor for the past year." All Might reveals, "someone who can take my place once my power is gone."

The three teens eyes widened as they slowly put two and two together looking at Izuku.

"And what exactly do you want with my son?" Shota said emotionlessly. Izuku's heartwarming at Aizawa regarding him as his son.

And here was the hard part, he thought. All Might knew it was probably going to be difficult asking his friend for permission to have his son be his successor, but he came this far, no turning back now.

"Shota, I'm sure you already knew this, but your son has the makings of a true hero. His actions today only proved this."

Aizawa's glare hardened on Izuku, "Yeah no kidding, which reminds me, you're grounded for a month."

"I'm grounded!"

"Yeah, what you did was incredibly reckless, regardless of whether you were saving someone. Not to mention breaking quirk laws."

"Tsk, shame shame Izuku, we expected better." Mirio said shaking his head, although his thumbs up to the boy showed he wasn't disappointed in his little bro.

Izuku simply nodded, not wanting to get in even more trouble. Letting All Might continue what he was saying.

All Might coughed into his hand before continuing, "Uh, yes as I was saying, Izuku was incredibly courageous and it was his actions that gave me the final push to choose him as my successor. Shota, I want to pass down OFA to Izuku."

Aizawa ran a hand down his face, unsure of what to say. While he knew Izuku had already probably accepted, he was still a bit on edge of whether it was safe for him to do so.

"You said his actions today was the push for you to choose him as your successor…does that mean there was someone else who you had in mind or something which was stopping you?" Aizawa asked, hoping to change the subject.

All Might chuckled not expecting this question. "Uh, well actually yes. There was one other person I had in mind, by recommendation of my old sidekick. However, Izuku was my choice."

"Who was it?" Izuku asked curious as to who else might've been worthy for OFA.

"Oh well, does it really matter?" All Might asked not wanting to make things awkward with the one in question sitting right beside his successor.

"Not really, but we're all just a bit curious" Mirio added.

"Yeah, yeah, yeah. Who else was good enough to be a candidate? They had to be really strong and brave and have a heart of a hero like my Izuk-kun if they were even considered, right?"

"Well, yes."

"Look, just answer the question, otherwise these three will continue to bug you." Aizawa said.

"If you really want to know then they're right beside you Izuku" All Might smiled.

Izuku looked to his right and saw his big bro sitting right next to him with a big smile on his face. At first Izuku thought he would get angry or maybe look a bit disappointed that Izuku had gotten OFA instead of him but instead like always he surprised him but acting in an entirely different way.

"IZU-BRO! Can you believe Sir thought I was worthy enough for All Might's quirk!" Mirio said teary eyed.

Bear hugging the young boy, Mirio continued to spout compliments about the two.

"We're gonna be the best pro heroes ever, aren't we Izu-bro! With All Might by your side and Night-Eye by mine there's no way we won't be the best superhero duo ever!"

Izuku wasn't sure whether to cry or laugh at his, at this point adopted brothers', antics.

"Yeah, def-definitely Miri-bro." Wiping his tears Izuku looked to Mirio before quietly asking, "So you're not mad I got OFA even though you were also being considered?"

Mirio grinned at the broccoli haired boy before laughing, "Nah, besides mastering my quirk was hard enough, can you imagine trying to master All Might's as well as mine! Ha, but don't worry I'll help you every step of the way!"

"You will?"

"Of course, you'll need help managing all that Poweeer!"

"Uh, what's that all about?" All Might asked.

Aizawa sighed, "Honestly, I don't even know. They've been doing that since I've met them."

All Might turned to the teens for answers.

"Oh yeah, Mirio says that before every attack he does, so does Izu-kun!" It's like how you say smash, they say Power." Nejire answered smiling fondly at the two boys wrestling.

"Indeed, if I didn't know any better, I'd say it powers up their moves" Tamaki whispered from his corner.

"So, I assume you're alright with Izuku accepting my power?"

"Not like I can stop the kid now." Aizawa drawled. "But I swear if that kid comes home not looking how he does now you'll pay for it." He growled.

"Uh, yeah got it."


"So how do we do this All Might?"

"Well my boy, One for All needs a proper vessel before it can be used, otherwise your limbs will explode."


All Might hurried to backtrack not wanting Izuku to back out of being his successor.

"But don't worry! Whatever you've been doing has made you more than ready, I swear!"

Izuku began to calm down, eyeing his mentor skeptically. When he didn't see any signs of deceit, he nodded his head.

"Thank the Mirio and Midoriya Road to U.A work out plan." Izuku said proudly.

"The what now?"

Izuku pulled out a stack of paper and handed it to All Might who leafed through it impressed, before handing it back.

"Not bad, I even noticed you added Martial arts to the mix. You truly planned everything out! I chose well for a successor." All Might yelled, before deflating back to his civilian persona.

Midoriya laughed, nodding his head. "Yeah, well Mirio and I made a promise to get into U.A together and I plan to keep it. So, what now?"

All Might shrugged, "Now's time for the ceremony!"

Plucking a piece of hair off his head All Might handed it to the boy, "Eat this!"

"What the heck why?" Izuku gagged.

"One for all has to be passed down through some sort of DNA, I figured this would be easier than blood or spit."

Izuku grumbled about how unhygienic this was, but agreed it was better than eating spit.

"Oh my god, did you really use a scented shampoo before coming here?!"

"I thought it might make the hair taste better." All Might said sheepishly.

Izuku shivered as he felt the hair go down his throat, "Uh, do you at least have water to wash it down?"

All Might's face dropped, not even thinking about giving his successor something to wash down his hair. "Uh, no I don't. Sorry."

"Seriously! Jeez, fine well what do we do now?"

All Might beamed at the young man. "Now we wait. It'll take a bit for you to digest the hair so in a few hours we should be ready to test out OFA and see how well it meshes with your power. For now, you can go do whatever you want but come back in about say three hours to test it out"

Izuku nodded his head, before going to visit his a few of his favorite pro hero teachers.

"Ragdoll jr.! What are you doing here, I thought we weren't seeing you until Friday at Dadzawa's!" Midnight cooed as she suffocated Izuku between her chest.

"Mmmphmph" Izuku mumbled.

Present Mic chuckled at the young teen, ever since Aizawa adopted the kid, him and Midnight had decided to be honorary Aunt and uncle, spoiling the kid whenever they could. Not that the kid didn't deserve it, but it helped that they received a photo of him, and his friends dressed as Eraser head, Midnight, and himself. Honestly kid's too pure for the world.

"Yeah lil' listener, not that we don't enjoy your visits" he added.

"I'm doing some extra training, but thought I'd just drop by to visit" he said smiling.

Midnight and Present Mic looked away from the bright smile, "Too pure."

After sitting down to speak with the two teachers, Izuku decided it was probably about time to head back to All Might for his training. Once back to the training room he was surprised to see his friends, and girlfriend there too.

"Mirio, Nejire, Tamaki what are you guys doing here?"

"Moral support!" they yelled, as they jumped to hug the younger boy.


All Might laughed at the teens, before answering truthfully, "Yes and No. They wouldn't stop asking Aizawa for updates on you, so we decided to let them watch you train."

Izuku clenched his chest, holding back his tears, "You guys…thank you"

"Well now that we have pleasantries done with, ready to get started?"

"Yeah, so how do I activate One for All?"

All Might stared at Izuku slightly sweating, "Well I'm not sure, you see One for All came to me quite easily, so I didn't really need that much training from my mentor."

Izuku blanched at his mentor, he was really started to have some second thoughts about this, but then again if he wanted to stand by Mirio's side he had to be the best and being trained by All Might was a good step forward.

"What about a technique when you use One for All?" Mirio offered.

All Might puffed back up into his original form at Mirio's idea. "Why yes, I do. When using my quirk, I usually clench my butt cheeks and yell SMASH!"

The three older teens, and Izuku held back laughing at the symbol of peace's explanation for how he used his power, looking in awe as he punched through almost every practice dummy in the training room.

Izuku stayed silent, rubbing his chin thought. I could probably use the same method as All Might if I didn't already have my original quirk. But obviously I must combine my quirk with One for all which means just trying to activate it with a punch won't work. If I can activate my quirk from any part of my body, then shouldn't it be the same for One for All. All Might said One for All was a strength enhancement quirk so does that mean it could enhance my flames? What if instead of trying to punch I try to…

Does he do that a lot?" All Might asked, watching as his successor continued to unravel how the best way to activate One for All.

"Oh yeah, all the time! You won't believe how many times we've been kicked out of places because of his little mumbling habit!" Nejire said with a fond look on her face.

"Yup, my little Izu-bro loves to over analyze things" Mirio laughed.

"I got it!" Izuku yelled.

Within moments of him announcing it Izuku shut his eyes and took a deep breath. Slowly taking a step back, his eyebrows furrowing as he began to summon One for All.

"Flame on!"

"Pfft, is that really how he activates his flames" All Might choked.

"Only when he's going full flame" Mirio said sheepishly.

It took a few minutes for the others to finally notice anything, and even before that they thought it was just a fluke given that his flames were the same color as the lightning arcs emitting off his body. But when their little green bean opened his eyes, that's when they noticed it, green lightning was surrounding his body mixing in with his emerald flames which were burning darker than usual.

"He did it!" Mirio shouted.

"Atta boy!" All Might shouted.

"That's my Izu-kun!" Nejire cheered.

"Yay." Tamaki mumbled.

Smiling at his family cheering him on, he took a deep breath, feeling the power of One for All rushing through his veins. Letting himself get used to the feeling before doing anything, Izuku decided to try and move while having One for All activated. Albeit a bit painful at first, he continued to move until it felt natural stopping at a certain point.


The four other occupants stared in surprise at the amount of power that had been released. The blast that he had shot was powerful enough to melt several cement blocks. Izuku stared in awe at the amount of power he had just used, his mind going crazy with the possibilities he could use of his pyrokinesis. If that was how enhance his flames were with OFA Izuku can't wait to see what he can do with the telekinesis portion of his quirk.

As it turns out though, the adrenaline rush he felt from having achieved this was the only thing stopping Izuku from feeling his destroyed arm.


"Did you see that, Tamaki! Izu-kun just destroyed those cement blocks. One second they were there, the next poof they were gone!" Nejire shouted.

"Yes, I did. I was right next to you." He whispered.


Izuku held back tears at his mentors' words, as well as the backlash of pain he was feeling. At least my arm didn't explode.

"Really, that's awesome." He croaked, "But All Might I think I might've over done it" Izuku said before passing out.

Immediately the three teens ran to their friend panicking, All Might more so then them because of Aizawa's words.

"Oh god I'm going to die, he's going to kill me! Hurry Mirio, get Izuku to Recovery girl before Aizawa finds us!"

"Roger that All Might sensei!" Immediately Mirio picked up Izuku and began running to the nurse's office with Nejire and Tamaki on his heels. All Might went to follow, but not before running into Aizawa.

"All Might, you wanna tell me why I just saw my son passed out in Mirio's arms with his arm a complete mess" he growled.

"Oh wow, well Shota funny story, well not exactly funny but...look Izuku!"

For once Aizawa will admit in being a complete fool and falling for All Might's words. When hearing that Izuku might've been behind him he turned around only to see no one there and turning back around and seeing the hero gone. He only got angrier at the number one hero that day.

"Well my boy, if I were to guess what happened I'd say your output of OFA was too high."

Izuku stared at All Might confused. He thought he handled the power quite well, but then looking at his bandaged arm he seconds guess himself.

"What I mean is while you were using 100 percent, your body right now can only use around 25 percent. Quite a feat all things considered. For now, I suggest you practice working with that output amount, so you don't end up in the infirmary again and I don't end up in trouble with Aizawa" he chuckled.

Izuku understood better now. He might've made his body a proper vessel, but he still needed better training.

"Okay All Might, I understand" he said grinning.

"I know you do and so long as you continue the Mirio and Midoriya Road to U.A plan you'll be more than ready for the entrance exams in a few months!"

A week later


Izuku grit his teeth as he let loose another stream of fire towards his opponent with a small percentage of one for all infused. When the smoke died down and he heard no noise he assumed that he had finally won a match. "Miri-" Izuku said.


"Brooooo!" Izuku went flying into the gym wall eyes turning into swirls as Mirio stood up from his spot in the ground.

"Game, set and Match, Izu-bro!"

"N-no fa-fair, you're practically un-untouch-untouchable" Izuku gasped as he gently pried himself from the wall.

"HAHAHAHA, not true Izu-bro. Despite the control I have on my quirk, one misstep and I'm done for. You've gotten good handling with your quirk, as well as being able to combine OFA with it, but it just so happens that I've gotten better" Mirio says smiling, putting a hand out to lift the younger boy.

Izuku sighed, not so much sad he lost against his big bro, but a bit disappointed at how far he was from Mirio's level. Looking at the tin tin copy he sees that he never even got a hit on him, while Mirio at least got several on him. However, the smile on Mirio's face helped bring his spirits up making him forget about his lost. He truly is amazing.

"He's right you know. Bar you, Izuku, I don't think I've seen anyone work as hard as Mirio to master their quirk. Just keep training and I'm sure you'll land a hit eventually" Aizawa smirked, entering the conversation.

Izuku smiled at Mirio nodding, a determined glint in his eye. "Yeah, you can bet on it!"

The day before the entrance exam Nejire had decide to take Izuku out to eat for a special date. Izuku had happily accepted feeling a day off form all his hectic training was much needed.

"Isn't this nice Izu-kun just you and me- "

"And me" Mirio piped in before going back to his food.

"And me" Tamaki whispered before going back to his food.

"Yeah, yeah and Tamaki and Mirio, out here enjoying the day before your entrance exam! Could you even think of a better date?"

Izuku couldn't help but laugh at his eccentric girlfriend's question. "Is this a date?"

Mirio and Tamaki didn't even try to hold back their laughter, while Nejire hugged Izuku for being so adorable. "Of course, it is Izu-bro, just think of Tamaki and I as the chaperones of the date so we can make sure Nejire doesn't try anything naughty towards you." Mirio joked.

"What, why me, what about Izuku! Why aren't you protecting my virtue?!" Nejire whined.

"Nejire, please."


Day of the entrance exam

"Okay, you're sure you have everything?" Aizawa asked.

Izuku ruffled through his bag, double and triple checking it to make sure he had all his supplies for the test.

"Yup, everything I need is here! Mirio and the others helped me pack last night" he smiled.

"Indeed, we did!" Mirio said popping up from the ground.

"Jesus Christ, Togata what the hell did I say about popping up like that!" Aizawa yelled.

"You said that he shouldn't do it and that it scares the hell out of you" Nejire said as she entered the front door.

"What the? Hadou, how the hell did you just come in, the door was locked!"

Nejire rocked back and forth on her feet hoping to look innocent before answering, "I have a spare key Aizawa sensei".

At this point the U.A. teacher was speechless at his students' actions. Looking around he noticed one person missing and dreading how he was going to enter.

"Hadou, explain how you have a spare key and why?" he sighed.

The older girl simply stared at the U.A. teacher before shrugging. Running a hand down his face he accepted the answer knowing he wasn't going to get anything else. "Fine whatever, where's Tamaki, and Kendo?"

"Over here sensei." The boy whispered from his corner.

"I was with Nejire, but I guess you didn't notice." He said downtrodden.

"And Kendo headed over to U.A. because she didn't want to get in trouble with you for breaking in, even though we technically aren't." Nejire scoffed.

"Oh my god, you know what I don't have time for this, and Tamaki I'm sorry I didn't notice you."

"It's alright."

"Nejire, return that key before you leave."


"Fine. And Mirio…please stop entering my apartment naked."

"Of course, sir!"

Aizawa let out a breath he didn't realizing he was holding after the three teens replied than looked to his son, "Izuku, don't you have an entrance exam to get to?"

Izuku nodded his head vehemently, remembering that he did in fact. "Oh, yeah I almost forgot!"

"And that's why we're here! To remind you!" Mirio announced while pulling his pants up.

"Yeah, yeah, yeah. And I couldn't let my Izu-kun go take a very important test without a good luck kiss!" Nejire said pounding her fist into her hand.

"I mean you could" Aizawa mumbled, starting to second guess whether he was ready for fatherhood.

"I'm here for moral support" Tamaki whispered.

Izuku blushed at his friends' actions, "Thanks guys this means a lot, I'll see you after the test is over okay!"

"Okay babe, but first this!" Before he could ask what, she was referring to Nejire quickly pulled him into her arms for a kiss, letting him go when someone cleared their throat.

"Test now." Aizawa says, rolling his eyes at his sons blushing face.

"Ri-right, yeah, test. I'll go now. Bye guys!"

"Good luck, Izuku" Tamaki whispered.

"Remember to use max Poweeer!" Mirio shouted, stifling his laughter at his lil' bros face.

Izuku paused in his steps turning around with a bright smile, "Max Poweeer!", turning back to head to his exam.