New thing I've been working on for a little while, never posted anything on it, but I do like what I have planned. Hopefully I can actually stick with it for a change. (A lot of this chapter was written back in mid-to-late 2019, and only recently finished.)

Thanks to Eclectic Bunny, Robert Waldron, GIGGY, Jesse Garcia and The-Anti-Akuma for supporting me on Pa Treon this month! I really appreciate it!

What constituted a quirk?

It was a question that had been asked for decades, ever since the first quirk had appeared, all those years ago.

Was a quirk purely physical?

No, that had been answered pretty quickly, the moment someone who could control electronics with their mind had appeared, five years after the first recorded quirk.

So, was it genetic?

All signs pointed to yes, in the sense that it was only possible to be born with a quirk.

Except in the instances where it wasn't genetic, and certain quirks could give or take other quirks. These quirks were merely speculated, of course, there was no possible way that a quirk could be given or taken away, considering exactly how a quirk worked.

So said the experts, at least.

Not that quirks were an exact science. There were so many quirks around that recording them all was a massive undertaking, and even then actually studying a quirk in detail actually required biological samples, and when many quirks didn't have easily accessible physical manifestations, that was a difficult task.

So, most people simply had to register their quirks when they got their IDs, like a driver's license or a passport. Typical government identification.

So, that was a lot of information. What did it actually mean?

It meant that having no quirk, out of every single possible quirk in the world, was a severe rarity.

And Izuku Midoriya had been dealing with being quirkless since his birth.

Much to his mother and father's disappointment.

Inko Midoriya had a quirk, and so did Hisashi Midoriya, so it was an interesting set of circumstances that had lead to Izuku's quirklessness.

And by interesting set of circumstances it was really quite uninteresting, considering it appeared to be a simple fluke of biology.

"What's he going to do in life without a quirk?" Hisashi asked his wife, as he sipped at the drink Inko had brought him, the two sitting in the living room, late in the evening.

Inko spared a glance at the closed door of Izuku's bedroom, thankful that the boy was asleep. "I don't know. Do we have any other options, though?"

Hisashi frowned, putting the cup down. "I don't like it, Inko. If you do this, it may end poorly for the both of us."

Inko let out a sigh, not meeting her husband's eyes. "I know. If we don't take the chance, though, he may resent us for the rest of his life."

The two sat in silence for moments, but to them it felt like hours.

"Fine. If it's what you think we should do, Inko, then do it."

Inko nodded, standing from her seat. "I'll contact Father, and let him know."

Hisashi scowled, looking away. "We should've splintered from him years ago, Inko, you know that."

Inko sighed once more. "I know, Hisashi, you've said it before. We need his help, though. We can't let Izuku go his entire life without a quirk."

Hisashi downed the rest of his tea, standing and walking to the kitchen, quickly rinsing the cup. "I know. I just… I feel like he's going to take our son from us. No matter what, we can't let that happen."

Inko nodded. "Trust me, Hisashi, I know that better than anyone. He may be my father, but he doesn't control me, no matter how much he believes he does. We'll owe him, but we'll pay that debt, not Izuku. We owe our son that much."

Hisashi nodded. "I'd best start on that, then. I'm going out, I'll be back late. Take care, darling."

He leaned close to his wife, the two sharing a kiss before Hisashi stepped out of the house, closing the front door behind him.

Leaving the only awake, living person in the Midoriya household with a difficult call to make.

ONE DECADE LATER

Inko watched her son arrive home, sporting another bruise, already on his way into his room, the walls of which were plastered with various posters of heroes.

Whenever he wasn't looking, Inko would scowl at that. She wished Izuku's obsession was less… childish, but it was what it was. His dream had always been for him to be a hero, and far be it from her to dissuade her son, but she wished it wasn't something so dangerous.

She didn't want him to get hurt.

The poor boy wanted to be a hero, even in his situation. He never stopped cheering on every hero he saw.

Hisashi had been maddened by it, and it was only the fact that it was his son that prevented him from snapping at the boy whenever he mentioned how cool the newest hero was, or how amazing it was that they stopped the latest heist, or how incredibly powerful and capable All Might was.

Speaking of her husband, the man had started taking more and more jobs as of late, away from home for sometimes weeks at a time, but that was because he was working overseas. She wasn't entirely happy with that, but she knew it was for the best. Her husband was not the most… careful of people, usually preferring to work through problems rather than around them.

Her son had inherited her husband's indomitable will and her own mental aptitude, something she was glad was not the other way around. She loved Hisashi with her entire heart, of course, but she knew her husband well.

Izuku, however, was a genius. Or, at least, he was a genius when it came to analyzing quirks. Inko had once taken a glance at one of his many journals, and had been absolutely amazed at the details that her son had included.

Of course, the boy had, thankfully, never made an accurate analysis of her quirk. His ability to analyze was a massive gift, but it was also a massive danger.

And that wasn't even mentioning the potential danger his quirk possessed.

Inko was snapped out of her thoughts as she realised she'd been staring at Izuku's closed door for the past five minutes.

She had katsudon to make, that would cheer him up.

It was funny, in a cruel, ironic sort of way, really.

When he was young, all he wanted to do was find out what his quirk was going to be.

He never got a quirk.

For someone so obsessed with quirks, to be quirkless, it made sense, but not from the angle he held.

It would make sense if he was jealous, envious of the quirks he witnessed, and yet…

Izuku was never jealous. He was never envious.

Sure, he wished he had a quirk, but not having one wasn't the end of the world.

So what if people he'd once called friends ridiculed him for it, so what if it meant that his chance of becoming a hero was so much more difficult than others, if solely by the limitations he had to work under.

It wasn't going to stop him. He wasn't going to let himself fail, he wasn't going to let people put him down, tell him he couldn't do what he always wanted to do.

It was his dream, to become a hero. His passion was heroes, his days and sometimes even his nights were spent studying and understanding heroes, villains and quirks, and he liked to think that he was well-versed in quirks, both in application and understanding.

Despite his own significant lack of one.

He wouldn't let it stop him.

His mother was so worried about him even attempting it, she had said it was too difficult, too dangerous, but he refused to listen to that. He knew it would be difficult, he knew it would be dangerous, and still he refused to give in.

Because giving in would mean giving up, and if there was one thing Izuku refused to do, above all else, it was give up.

Izuku sat in his chair, turning on his computer and beginning to search through today's headlines, interest already perked at the newest debut of heroes, and a recent development in a missing person's case that had been reported to the news.

It was his afternoon routine, now. He'd get home, and begin compiling more information, details about quirks, all to give him an edge, an understanding.

It could only help, not hinder, and having the ability to recall that knowledge was especially useful for homework. Any time Quirk Histories was the subject of class he was using what he'd studied to ace all the pop quizzes his teacher was so fond of giving the class, much to their disappointment.

A knock on his door brought him out of his thoughts, and he quickly stood, closing the browser.

"Izuku, dinner! We're having katsudon!" His mother called out, and Izuku was quick to exit his room, noting that more time had passed than he had expected.

Had he really been that lost in thought?

It didn't really matter though, he was hungry, and katsudon, well. It was his favourite, why wouldn't it be?

Inko watched her son dig in, her own food barely touched. She was worried, still, but she wasn't going to ask about the bruise. Too many times had she questioned her son, and too many times had he either refused to explain or simply given a convenient excuse.

So, the two ate in silence.

Another day, another miserable end to school. It was almost a habit, now, as he ended up invariably rescuing another of his damaged journals from an early grave, courtesy of Kacchan.

Katsuki Bakugou was a bully, that much was obvious from looking at him.

But he was also someone Izuku looked up to, if only for the sheer force of nature that the teen represented.

He never gave up, never lost a fight. Sure, it had a lot to do with his quirk, but no one was born a hero. It required work, something that Izuku knew the teen had done.

Izuku liked to imagine, sometimes, that if he had gotten a quirk, he and Kacchan would've still been best friends, an unstoppable duo of pure heroism.

It was a pipe-dream, a complete fantasy, but Izuku entertained it nonetheless.

Today, he was fishing his latest journal out of a pool of water, burns around the edges from the angry, aggressive teen's explosive quirk.

Number 13, to be specific.

At the least, all the damage was as consistent with thirteen as it was with one through twelve, as Kacchan had done various bits of damage to all of them over the past years.

But, as it was, it was time for Izuku to head home.

To cower.

The thought was as intrusive as it was unacceptable, and Izuku shook his head to clear his mind, straightening his shoulders.

He wasn't going to walk out of here like he was afraid. He was going to straighten up, and walk with confidence.

Okay, so he was going to walk out of here. With confidence, probably not.

At least he'd try not to attract attention.

He was, however, alone on this path.

The path out of school was, without a doubt, empty, devoid of other students.

Had he really taken that long to rescue his journal?

He'd been getting distracted lately. Things that should be fleeting thoughts were sticking with him for longer.

Or, alternately, he was just becoming more and more aware of how much time his thoughts seemed to take up.

He would have debated this point further if something hadn't swallowed him up from behind.

"Mmrrgh!" Izuku screamed through thick, viscous liquid, struggling as it began to entomb him within its murky green muck.

"Quit struggling! It'll only hurt for, oh, forty-five seconds or so. I'm just tryin' to take control of your body!" The mud said, and despite what was without a doubt a life-threatening situation, Izuku still had the wherewithal to question exactly how the mud was talking.

It came to him in a flash of what might've seemed like brilliance, but in reality it was just an average observation.

The person trying to kill him was a villain made of some kind of sludge.

"Don't worry, the pain'll stop soon after that!" The sludge uttered, almost as if he was muttering to himself. "Still, to think that he'd show up in this dump."

Izuku's mind was still racing. How'd he end up being the one in this situation?

Why not someone who could at least fight back?

'I don't want to die!'

It was the only thought rushing through his mind now, as his throat filled with muck, his vision dimming as the edge of his peripherals worked themselves closer and closer to the center of his sight.

He was losing consciousness.

"Not to worry! I am here!"

The voice that Izuku knew beat for beat, note for note, etched into his mind. A thousand times, ten thousand times, had he heard that voice.

To think his final moments were to be of a hallucination of the world's greatest hero.

The irony was almost as palpable as the sludge that was slowly working its way into his lungs.

"Texas Smash!"

The final words that Izuku would ever hear was the name of the special move that had saved so many lives. Izuku would have sobbed in morbid humour at that if he could.

So when the sheer wind pressure blew the viscous villain off of him and splattered it across the pavement, the boy suddenly able to breathe, it was possibly the most insane relief he'd ever felt.

Because it meant it wasn't a hallucination. It wasn't his final thoughts.

It was All Might himself, standing right in front of him, checking him for injuries.

"Are you alright, young man?"

Izuku didn't respond, shock and awe flooding his mind.

Then, it all clicked, and Izuku did respond. "What?!"

"Ah, sorry about that! He slipped my grasp, my apologies! I'm not usually so sloppy!"

It was honestly impressive to watch All Might normally, and watching him effectively use an empty bottle to scoop up the villain was even more so.

"Well, I'd best turn this villain over to the proper authorities! Farewell, young man!"

Izuku panicked. "W-wait! Can I have your autograph!" He flipped open his book to what he knew was a blank page, only to see the autograph in question already written in.

If anything could be said about All Might, it was that he was a fast worker.

But Izuku had another question. One that he was about to ask as All Might bent at the knees, and prepared to leap.

Izuku obviously hadn't made enough dumb decisions today, and reached out.

It felt like only a moment passed before the teen found himself clinging desperately to All Might's leg, dangling in the wind as the hero soared through the air.

"What do you think you're doing, young man?!" The hero exclaimed in shock. "Let go!"

Izuku frantically shook his head. He'd had enough of dumb decisions today, he thought, and letting go now was certainly a dumb decision, something that seemed to register with the number 1 hero at the same time.

The landing was rough, but Izuku didn't die, so he had to at least be thankful for that. Considering the situation, it was impressive he hadn't lost his grip and plummeted to his death.

"I must go, young man, evil waits for no man!" All Might practically announced, but Izuku wasn't going to waste his chance, once he'd recovered his breath again.

"Can I become a hero, even without a quirk?"

The question stalled the hero.

"Is it possible for someone like me to become someone like you?" Izuku continued, seizing his chance.

His eyes were closed now, head tilted down, not looking at the hero as the man struggled, body contorting in pain.

"I always wanted to become a hero! Just like you!" Izuku said, looking up at the gangly stranger that stood in front of him.

"What?!"

Izuku fell backwards, hands scrabbling against the rooftop as he backed away from the man he had thought was All Might. "You… you aren't All Might? You're an imposter?!"

The spindly man sighed. "No, kid, I'm All Might."

Perhaps it would have been somewhat less dramatic if he hadn't proceeded to let out a cough of blood immediately afterwards.

"I- but… how?!" Izuku exclaimed in shock and horror, though he was starting to lean more towards the horror side of the situation.

The skinny form of All Might sighed again. "I was injured, five years ago. I lost a lot of internal organs, it looked like a diagram of the body drawn by a four-year-old. I'm emaciated, terrifying, and stuck to a time limit of around three hours."

"Five years ago… when you fought against Toxic Chainsaw?"

All Might laughed at that, though it lacked humour. "You know your stuff, kid. The Symbol Of Peace can't afford to bow to the forces of evil. What I just told you isn't public knowledge. I need you to keep it to yourself."

Izuku nodded frantically.

"As for what you asked… No. Pro's put their lives at stake every day, that's a part of being a hero. Being a hero without a quirk… it just isn't possible. There are too many situations where it becomes more of a hindrance for other heroes."

It hit Izuku like a truck; hard, fast, and without mercy.

It was raw truth, something he'd been hoping to avoid, if subconsciously.

"I-I see…" He muttered.

"If it's saving lives that matters to you, become a police officer. The job may be ridiculed, but it is an honest, admirable line of work."

Izuku couldn't meet the man's eyes.

"There's nothing wrong with dreaming, kid. Just… be careful not to obscure the facts."

All Might left Izuku on the roof, and the teen stood there.

He didn't really know how to feel. Was it a good thing that he'd been told it now? Instead of years down the line, when he made a mistake?

Or was it as heartbreaking as it felt. Izuku didn't know. That was probably still to do with the shock.

His thoughts were effectively knocked from his head as an explosion shook the block, echoing out over the city.

Izuku quickly ran over to the nearest ledge, peering over towards where the sound had come from.

He could see people crowding in the distance, not too far from the building he was atop. He could also see the Pro Hero Mt Lady, at her maximum size, peering between two buildings she couldn't fit between.

He had to get a closer look at what was going on.

Izuku sprinted down the stairs, taking them two, three at a time, and soon his feet were pounding the pavement as he tried to understand what was going on.

And then, as he rounded the corner, he realised exactly what was going on, much to his continued shock and horror.

And, this time, he decided he was going to feel shame along with those previous feelings.

In front of him, surrounded by fire, smoke, and smouldering buildings, was Katsuki Bakugou, almost completely encompassed by the sludge villain that had nearly killed Izuku.

The very same sludge villain that All Might had pocketed in the very same leg that Izuku had grabbed.

"We can't get close!" Someone shouted, a hero, but Izuku didn't even look, for once, instead all his attention focused on Kacchan's face.

The teen, the strongest member of his school, the aggressive, self-centered bully.

Terrified beyond belief.

Izuku felt his legs moving before he realised they were, propelling them of their own accord, throwing him past Kamui Woods, the hero who had set up a barrier to protect civilians.

There was only so much the hero could do to stop people passing, and it wasn't like there were many people so suicidal that they'd throw themselves at a villain.

Especially not one without a quirk.

So what did he think he could do?

Then again, considering how he'd ended up in this situation, he hadn't done much thinking at all.

This was his fault, though. He had to at least try and fix it.

What did he have at his disposal?

A quick run down answered that question. Nothing but his bag, and his body.

The bag was good enough.

"Aargh!" Izuku shouted, if only to distract the villain, and he threw the bag as it turned to look at him, shock and surprise on its sludge-like face as the fabric bag hit him in the face.

It didn't do a single thing to the villain, of course, the bag wasn't laden with explosives or some kind of sludge-repellent, but it did seem to stun the villain all the same, something Izuku was thankful for as he closed the distance and began tearing chunks of mud off of Bakugou.

It was slow work, of course, and seeing as he had quite literally less than a second to try and help, it didn't do much.

And then, for the second time in less than an hour, Izuku felt the incredible overpressure of wind against his skin as All Might Detroit-Smashed the sludge into seeming non-existence.

He also, through sheer power, changed the weather. Which, to be fair, was an incredible feat in and of itself, though it was considerably less important considering that Izuku and Bakugou were now no longer in life-threatening danger, Izuku for the second time today.

And then, with a single nod in Izuku's direction, All Might leapt into the stratosphere, this time without a young boy in tow.

Izuku floundered, unable to think of what to do next.

Someone else had an idea, though, and suddenly Izuku found himself being lectured by Death Arms himself, another of the heroes who had responded to the incident.

Others began the cleanup, collecting the scattered remains of the sludge villain, and from the looks of things, he was still alive.

Izuku didn't know what to think about that.

And then he found himself being sent along his way, effectively ordered home.

That was something Izuku was more than willing to do.

He just wished he got the opportunity to apologize to All Might.

The opportunity came, unexpectedly, almost immediately after Kacchan had shouted something that sounded vaguely like a really angry thank-you, to which Izuku had been surprised. The teen was usually more in favour of either ignoring his presence or ridiculing it. Actual, direct anger meant that Bakugou was recognizing him as an actual person. That was a step forward.

Speaking of stepping forward, Izuku had been about to do just that when the muscular form of All Might himself sprinted around the corner, with a familiar shout of "I am here!"

"Wah! All Might!" Izuku let loose, stumbling back a step in surprise. "Weren't you surrounded by reporters?!"

The hulking man laughed his booming laugh. "As if I couldn't avoid a bunch of reporters! I-"

His sentence was cut short as he coughed hard, blood cascading out of his mouth in a torrent of red.

"I owe you an apology," The smaller form of All Might said, once he'd recovered. "I spoke harshly, and rashly. I didn't consider what you said fully. You running in to help that boy, your courage in the face of villainy, that was one of the most heroic things I've seen in a long time."

Izuku's eyes widened.

"I believe you have the capability to become the hero you've always wanted to be, but that isn't all."

Izuku's eyes couldn't physically get any wider without external effort.

"I want you to become my successor."

So many things echoed about in Izuku's mind at that very moment, and he just about passed out. Shock, elation, fear, trepidation, surprise and worry all fought for emotional supremacy, but the victory went to confusion, for the time being.

"Successor? What do you mean, All Might?" He asked, all the while trying to clamp down on the tears that threatened to spill forth from what felt like every part of his face.

"I want you to inherit my quirk."

Izuku gave up on trying not to pass out.

"I'm worried for him, Hisashi."

"As am I, Inko. I trust him, though. He'll make the decision he wants to make, and there's nothing we can do to stop him."

"And if he decides to become a hero?"

"Then he becomes a hero. It doesn't change anything."

"Doesn't it?!"

"I'm not even in the country, Inko. Even if I was, you know I'd handle it with dignity."

Inko shook her head. "You couldn't possibly believe our Izuku would back down just like that."

Hisashi sighed. "Perhaps not. So, he finds out the truth. He'll have a decision to make, and we have to respect that decision, just like he has to respect ours."

"You always know what to say, Burning Dragon."

"And you always were one to worry, Kinetic. Do not be afraid, dear. From the way he always seems to be thinking everything through, he most definitely inherited your mind."

Inko laughed a quiet laugh. "If only he hadn't inherited your stubbornness as well."

Hopefully you enjoyed the first little taste of Mutatis Mutandis. It plays out a lot like canon, but I tried to show a few little tidbits that everything isn't the same as it always is. Chapter 2 is already underway, and will be posted once it's finished. If anyone has any ideas for what kinda quirk they'd like to see, I'm open to suggestions, none of what I have planned is set in stone.

And, as always, see you next chapter!
~AFatFlyingWhale