To Build A Hero

by gamemasterOSB

Izuku Midoriya, unfortunately lost the genetic lottery when he was deemed quirkless. But losing one battle does not mean the war is over. If Izuku could not have a strong quirk by luck, he'd just have to build his own. With new friends and family at his side, watch as Izuku builds his path to being a hero. The Quirkless Hero: Kamen Rider Build

2. Chapter 1: To Build A Quirk

AN: Here is the first actual chapter for this fanfiction, because I consider the last chapter to be a prologue. This is honestly very fun to write, but I know I am inexperienced, so please leave your feedback and criticism so I can work to improve. Thank you for reading

It's been four years since Izuku moved to I-Island and met Melissa, since then, not a day has gone by where he hasn't seen something that amazed him, be it something Mr. Shield or Melissa made, or something he saw on the island. He'd been having the time of his life, and it was just about to get even better. He saw Melissa sitting at their usual lunch table, fiddling around with something that looked like metal cloth. He made a b-line for her, barely able to contain his excitement. "Melissa!"

Melissa looked up from her project to see Izuku standing over her with one of his classic composition notebooks, but it looked different, it had scraps of paper peeking out of all sides, and the spine looked like it was ready to fall apart. "Izuku, what's up, you look awfully chipper today"

"Why wouldn't I be, I've finally got it figured out!" Izuku said, a light in his eyes.

"Got what figured out?" Melissa asked, she'd never seen him quite this excited, it was almost alarming.

"How we're going to become heroes! Let me show you." Izuku said as he sat down next to Melissa. He put the tattered notebook down on the table, the title read "The Build System". Izuku opened the notebook up to a page, on it was a sketch of a box, on the far side seemed to be a hand crank, and it had a pair of openings where you could place something.

Melissa looked over the drawing, still unsure as to what she was looking at, attempting to read the hastily written notes that surrounded it. She looked back at Izuku, he still had that look of excitement on his face, so she asked: "Izuku, what am I looking at, it's not bad, I just don't understand it."

Izuku realized his shortcoming, cleared his throat and responded. "This is the Build System, it's how we're going to become heroes, I've been brainstorming it for the past year and a half!"

Melissa looked at him still confused, "That's great and all, but how is it going to do that?"

Izuku looked flipped through the notebook to a different page, illustrated with a crude double helix. "Every human has DNA, and all quirks also have an impact on this DNA as seen in the quirk cells of people. With us being quirkless, we lack these quirk cells, but this device should be able to replicate these cells and be able to grant us what is effectively a temporary quirk!"

"Temporary quirk? Izu, I hope you know how crazy you sound right now"

"And why is it crazy, normal pro heroes use support items to improve their quirks, what is so farfetched about using support items to make our own quirk"

"For starters, where are we going to get the necessary quirk cells to pull this off?"

"Mel, we literally live on a floating island thats main purpose is to conduct quirk research, I'm sure that there have to be a few people who'd be willing to help"

She sighed "Alright, show me more of what you have before we get ahead of ourselves"

He smirked "Too late, I broke the sound barrier running over to you. But look here, these two slots will be used as an input for the quirk cells" he flips a page "and these bottles will be used to store and access them, theoretically allowing us to combine the aspects of two different quirks and use them simultaneously, each stabilizing the other"

Melissa sighed again, he had lost her around "bottles" but the more she looked over his notes, the more his idea began to make sense, somehow, and look like it could be possible. While certain pages lacked order, most of them resembled the half-dozen notebooks he had on quirk research. The notes were neat and organized, most of the information pertained to quirk cells, their extraction and potential ability replication.

"Alright, quick question, are you sure this is safe? I mean what your saying is basically to mess with our DNA and give us quirks, even if it is temporary"

"That's what the driver is for! The driver will act as a catalyst to use the quirk cells, it's kinda like quirk armor if anything, but with the ability to mix and match quirks to best fit a scenario, think about it Mel, we can be the most versatile heroes out there, if there is an infinite number of quirks that we can build a hero with infinite potential! Truly Plus Ultra!" He claimed with one fist held in the air in an All Might-esque fashion.

Melissa looked at Izuku, and let out a soft giggle "Well, you've at least got the passion for it. Alright, as your best friend and the obvious brains of this operation I'll help."

"Brains! This was my idea! The first of many of the genius hero Izuku Midoriya!" He claimed with his chest puffed out with pride. That was until he once again made eye contact with Melissa and they both broke out into laughter.

"To think that the little shrub who lost his mom, would have this much confidence now"

"I'll have you know that said shrub had the pleasure to grow up alongside one of the future's best heroes, so some of your confidence must have rubbed off on me" Izuku said with a bright smile.

Melissa blushed as she looked down "Y-you really mean that, about the best hero thing?"

His smile grew wider "Of course! After all, you've already got the brains, we've been staying physically fit our entire lives, and all we need is proper fire power. And once we get this driver working the last thing in our way to being heroes is that piece of plastic, they call a license" He raised his fist and stared at her, eyes filled with motivation "We are going to make our dreams a reality and build our future as the first quirkless heroes, that's what we promised right?"

Melissa couldn't help but smile, Izuku's was contagious, she nodded her head, and met his fist with her own. "Of course! Can't let you have all the fun" She then grabbed him and pulled him into a hug which he gladly reciprocated "the best heroes we can be, together"

– – – – – – – – – – – – – – – – – – – – – – – Later – – – – – – – – – – – – – – – – – – – – – – – –

David Shield had never heard something so crazy, yet so genius in all his life, and he'd heard Toshinori say some crazy things. Their system looked good on paper, but what all would be necessary to make it real? Could it even become real? And how safe would it really be? And most importantly if it was dangerous, how to tell Inko. Over the years, due to the close friendship of their kids he and Inko had talked a lot, and one thing was abundantly clear: while she would support Izuku's dreams, she was absolutely terrifying whenever Izuku was being reckless. It's the same reason that David makes sure to lock all sharp objects whenever Inko visits, telekinesis can be scary when several tiny knives are accessible. She turned a good stress ball into a pin cushion that way. So hesitantly he opened his lab to the two aspiring heroes while directly supervising their work to ensure that Inko would have nothing to worry about.

That lack of worry lasted approximately one month until Izuku was found stuck to a wall, upside down due to the stasis quirk of another researcher on the island. He was only found due to how loud Melissa was laughing when she found him in the hallway. That was a fun conversation with Inko. But Izuku, in an act of true heroism, managed to distract his mother with his excitement of experiencing the quirk firsthand and its successful extraction into a bottle. The next five months were spent requesting, extracting, getting Izuku out of whatever condition he'd gotten himself into, and developing the technology to refine the quirk bottles into the usable state that they calculated them to need to be in for proper use in the driver.

During the near six months Izuku and Melisa had been working on the driver system, they had made a few discoveries, first, when inserting two bottles into the driver some quirks interfered with each other, these quirks were separated into two categories organic and inorganic, two different bottles of the same category produced this interference. Second, not all quirks had a one to one transition into the quirk in the bottle: for example the stasis quirk when put in bottle form was registered as Lock, a girl who's quirk was a simple mutation that gave her cat ears and a tail produced a Tiger bottle, but someone who's quirk that was labeled "cannon" or the ability to launch anything due to a small explosion produced by igniting the hairs on their body led to a Pirate bottle. Or even a simple telepathy quirk produced a smartphone bottle. And third it appeared that some bottles had greater synergy with other bottles, due to this relationship it was calculated that the theoretical optimal combination, or Best Match, could result in the strongest versions of quirk combination. The driver was then calibrated using these equations, predictions, and discoveries to detect when a Best Match occurred. After all of their testing and gathering, 8 bottles were produced, unfortunately with a disproportionate six to two ratio of organic and inorganic bottles.

Now for the next year numerous iterations of the driver were tested, and Izuku was more than willing to test each one himself, only to be electrocuted after each failed attempt due to the feedback of the driver. After the 24th iteration's failure, Melissa spoke to a stunned Izuku on the floor

"You okay down there Mr. Genius Hero~"

"You're lucky I'm the one testing this"

"And why is that" Melissa responded with a smirk

"Because if I had feeling in my legs, I'd kick you right now for calling me an idiot"

"I never said idiot, in fact I called you a genius, so where is my thanks"

"Ah yes, thank you for letting me do all the tests of the driver instead of swapping each time. I am truly grateful for the constant shocks to my nervous system"

"Hey, it was your idea after all~, it only makes sense that you'd test it" she stated "at least the paralysis appears to be reducing with each attempt"

"But is that due our design improving, or my tolerance for electric shocks increasing, at this point I may develop a lightning rod quirk before the driver is ready"

"Who knows, so, wanna do another run or are we done for the day"

"Unless you can revive my legs, I think I've had enough shocks for this testing segment. Let's look at the data and try to isolate our issue"

After another 30 minutes of Izuku laying on the ground, he eventually rose and walked with Melissa to check the data they collected. After running physical tests on Izuku to ensure that he was still physically fine, they went over their findings with Melissa's father.

"Over the past 8 months of testing, while no successful transformation has occurred, we have noticed an increase in your physical characteristics." David started

"Your reaction speed has improved dramatically, and your top strength and speed have increased by roughly eighteen percent" Melissa continued

"So, what, instead of creating a support item, we made the ultimate workout program?" Izuku questioned

"No, because if it was it would have been able to work for everyone"

"What do you mean by that dad?" Melissa questioned

"One of our researchers willingly tested the driver in order to produce a comparison case, the driver had a negative reaction to him and effectively attacked the quirk cells in his body, luckily we were able to stop the driver before too much damage was caused."

"So, you're saying, only quirkless people can use the driver?"

"Essentially, yes, the driver attempts to empower you on a physical level, artificially enhancing you with the "quirk armor" concept you constructed; however, these specifications were designed for you two, who are quirkless. I theorize that the driver and bottle system Izuku designed may only function safely for those who lack any quirk cells to begin with, therefore there is no interference from the driver. It is possible that this is the same reason for the "bottle pairing" situation where we need an organic and inorganic bottle to function, someone with a quirk already has one of the two, therefore the interference is attacking them in order to remedy this."

"So how do we know when this is safe to use?"

"I have a theory: Based on the current statistics I've gathered, and the trend of the shock having a gradual reduced effect on Izuku's body, I believe that a certain physical threshold is required to properly transform, I've dubbed this threshold as hazard levels, which thanks to horrendous equation, we can determine your current level. As of now, Izuku is at Hazard level 2.8, Melissa you are at 2.2. I am at 1.3. However, I have measured all of the hazard levels of our fellow researchers out of those with quirks, none of them have reached a 2, the highest being a 1.5 and that was the researcher who tested the driver. I theorize that each time you use the driver, and expose yourself to its effects your hazard level gradually rises"

"So Mr. Shield, what level will we need for the driver to properly work?" Izuku asked, his eyes widening in excitement at the discovery

"My current calculations have predicted it to be around Hazard Level 3. Which is why 3 your current level has not hit that yet in my calculations, assuming 3 is the threshold necessary to properly use the driver means that most quirkless people would need the near constant exposure and constant testing for roughly eight to nine months to even come close, assuming they have a similar physical condition of course"

"What does physical condition have to do with the hazard level?"

"Simple, as hazard level goes up so does your strength, speed, and general fitness"

"So if we reach hazard level 3, then Izuku should finally meet the specifications to be able to transform!"

"And I just got the feeling back in my toes, let's go Mel!"

They go back to the testing area accompanied by David, and as Izuku steps into the isolated room he thinks "Hazard level 2.8, if using the driver more increases it faster then the longer I can endure the more it should rise, so I won't stop until I transform, I can't stop, not when our dreams are right in front of us"

"Izuku are you ready?" David asks through a speaker

"I've been waiting my whole life for this. Let's do this"

Izuku places two bottles in the driver, the speaker in the driver produces

Pirate - Smartphone

"Let's be a hero" Izuku begins to crank the handle, and the feedback of the driver begins to electrocute him. As he screams out in pain Melissa looks in a soft horror as her best friend is constantly enduring the tests.

"Izuku! It's not working, stop please"

"LEVEL!"

"Wha-"

"WHATS MY HAZARD LEVEL?!"

"2.9 and rising" David states

"THEN I'LL KEEP GOING!" As Izuku continuously cranks, the charts depicting his hazard level slowly level out, and eventually display a 3.0. Once the 3.0 is hit the electrocution stops and Izuku collapses to the floor.

"Izu!"

Slowly he gets back to his feet, gasping for air, "I got a good feeling about this one, after all the shocks stopped before I stopped cranking"

"You don't look to be in any condition to continue testing, please stop here for today." She pleads

"Sorry Mel, but when a hero is banged up with their back to the wall, they wouldn't quit, SO NEITHER WILL I. ESPECIALLY NOT WITH OUR DREAM RIGHT IN FRONT OF US. WE WILL BUILD A FUTURE WHERE WE CAN BE HEROES AND I WON'T STOP UNTIL WE GET THERE!" He reloads the bottles into the driver

Pirate - Smartphone

Are you ready?!

Izuku cranks the driver as tubes and frames build around him, gradually filling into the shape of a suit, one half in front of him and the other behind him. He looks up at the glass and stares at Melissa, eyes filled with determination, and he raises his right hand into the air.

"Henshin!"

After that one word, the frames converge onto Izuku, a quick burst of steam erupts, and there stands Izuku donning a teal and blue set of armor. Slowly opening and closing his fists. One thought crosses all three of their minds: It worked

"Izuku, are you ok!?" Melissa shouts as she runs up to him

"I'm better than ok Mel, this feels incredible, we did it! It worked! WE BUILT A QUIRK!"

"Build, huh, you use that word a lot, saying how we are going to 'build' our future, so this quirk is our Build huh?"

"Our build? Yeah, I like the sound of it, the Quirkless Hero: Build! Now then we still have some test runs to do; so, let's start the experiment"

Next Chapter Preview:

Izuku: We did it, we can be heroes!

Melissa: Yeah, but you still need proper training

Izuku: So, let's go

Melissa: Go were

Izuku: Where else? To fight crime

Melissa: HUUUH?!

Next time on To Build a Hero:

To Build a Reputation