AN: Hello everyone, sorry for the longer wait, I had my first round of exams, so I needed to prepare. Now then time to answer the comments

adislt: Theoretically I could make my own bottle if I wanted to. However, regarding the fullbottles I plan to stick to the canon list but utilize some that didn't get to shine during the run of Build.

sardarhassan503: Glad you liked the chapter. I can confirm that I have plans for who will be the other riders, but I will not confirm anything here. Regarding the length of the chapters, I attempt to find a natural stopping point, rather than force a chapter to be longer. Don't worry I have plenty of content planned and I hope you continue to enjoy!

Light Hero Kaiser: Glad you are enjoying the fic!

CCSakuraforever: Me alegro de que te guste la historia. En cuanto al trabajo del héroe, será diferente al canon. En cuanto a la escuela, tengo planes que se plantearán pronto. Espero que sigan disfrutando, gracias por leer.

(Sorry If I messed up, English is my primary language, and I had my friend translate. Here is the English if anyone is curious: "I am glad that you are enjoying the story. Regarding Hero work, it will be different than canon. Regarding school, I have plans that will be brought up soon. I hope you continue to enjoy, thank you for reading."

Blazingen1: I LIVE! And the chapter drops. NOW!

– – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – –

After welcoming Kirishima into their friend group, Melissa and Izuku were led to the gym that Kirishima frequented.

"Wow, and here I thought you had your doubts. But look at you even when you were not one-hundred percent confident you were still putting in work" Izuku said with a smirk, while looking over the gym. "They even got a ring in the middle, so we can do sparring during our workouts"

"Well, I guess even with others saying I can't I still wanted to try to follow my dream you know?"

"Trust me, this green idiot and I have been working for our dreams since we were six, there is nothing to be ashamed of Kirishima" Melissa said with a smile.

"Six?! Jeez now your making my past year of work seem small in comparison"

"Nonsense, most of our years were spent trying to make up for our lack of quirks to give us an edge, so I guess in that regard we are closer to an even playing field between the two of us. Plus we still have five years before we are even old enough to get into UA. Plenty of time to improve" Melissa responded

Kirishima beamed before nodding "Yeah! Thanks for the manly words of encouragement Melissa!"

Izuku smirked, "Well, we can do more than encourage, now you have workout and sparring partners, we'll definitely be able to prepare ourselves for UA!"

The next thing Kirishima knew, he had done a work out and was in the the ring about to spar against Melissa.

"Are you sure about this? I know you said you'd trained and that Izuku is strong, but you I still managed to use the heavier weights today, I don't want to hurt you" Kirishima asked

"Scared you're gonna lose?" Melissa taunted.

Kirishima, not wanting to hurt his new friend hesitated when Izuku called for the match to start, the next thing he new Melissa had crossed the distance of the ring and Kirishima was slammed on his back staring at the ceiling

"How did you do that Melissa?" Kirishima questioned.

"You think I could hang around this shrub head and not train with him?" Melissa responded pointing at Izuku. "Your first mistake was to assume because I couldn't lift as much that I was weaker, you may have power, but I have years of technique from sparring, your second mistake was to hesitate, in a real battle there is no countdown. So take advantage of that while we have it"

"SO MANLY! Alright let's go again!"

After several more spars, the trio eventually went to their respective homes. Izuku and Melissa had decided to head down to the lab to work before turning in for the night.

"Hey, Izu quick question" She asked while walking into the lab

"Shoot"

"That capture bottle you had after your "debut" do you still have it?"

"Of course, why"

"Simple, I've got the purifier working, and I'd like a test sample to make sure it's running properly"

Izuku quickly turned to face her, stared directly into her eyes, before a massive smile broke out on his face as he rushed over to her, picking her up in a hug and spinning her around. "Melissa, you are the BEST! This means we can finally start working on new bottles again. Oh, I wonder what it will be. Hopefully an inorganic one, we need more of those. Ehh who cares though we are getting new bottles."

She laughed while being spun "Izu, please put me down, also you're rambling again. Plus remember this is a test to make sure it still works so there is the risk that we lose the sample."

"We risk losing the sample if the lab explodes, I see no difference. Besides, I trust you, you are tied for the smartest person in the room after all"

"Tied?" She said raising an eyebrow "Hah, you'd be lost without me"

He replied with a smirk "Yes, yes I would. I would not be nearly this good with nano-tech without you, the armor would still be a concept without you"

"Wow, no snark, no sarcasm, has my Izu finally learned some humility" she said playfully punching his shoulder

Izuku rolled his eyes before responding "I can show gratitude, besides I don't think I can one up this yet. You and your father were essential in getting the purifier to work, without it my "debut" would not have even happened. So, thanks for sticking by this intelligent idiot's side for all these years"

Melissa simply smiled "Of course, after all, we are a team right" she then held out her fist "First quirkless heroes, right?"

He met her fist with his own "You know it! Now let's see what this bottle becomes, would you like to do the honors Mel?" he said offering the full capture bottle

"Gladly, give me a moment." She then walked over to a giant rectangular machine and stepped inside, fitting the bottle in an input slot and began executing command after command in a console before finally hitting the enter key and walking out of the box. "And now we wait"

"Oooh, the excitement is killing me over here I can't wait to test it out" he said with a smile

"And I hope it's another inorganic, we need more of those, as we are now inorganics are much more valuable to Build's versatility"

"I know, but it's not like we can rig the odds of what we get, the quirk decides how it wants to be bottled. If only there wa-" he spoke before getting cut off by a microwave ding. "New bottle!" he rushed over and pulled it out of the microwave looking bottle dispenser "and it's a. Hedgehog?"

Melissa sighed "you know given that the criminal you plucked it from had some sort of spike quirk, a hedgehog seems pretty normal"

"But why not a porcupine, or a pufferfish, or-" He started before being cut off by a finger to his lips

"Theorize later, test now, I'm curious if it's a best match candidate"

"Right! Come on, hedgehog, let's see it!"

Hedgehog – Smartphone

No follow up noise was made

Hedgehog – Lock

They both sighed, and Izuku took a seat before speaking: "nope, who knows how many combinations are possible with the amount of quirks in the world, plus we only have two inorganic to test. Man, this is the worst"

"If it's any consolation you are right, we only have two inorganics, therefore once we get more of those, we are more likely to get a match due to the number of combinations that become accessible. But let's end this on a high note, are you thinking what I'm thinking"

They both faced each other, smirking "Yep, let's see what this little guy can do"

Leaving the loaded bottles in the driver, Izuku began to crank.

Henshin!

– – – – – – – – – – – – – – – – – – – – – – A few days later – – – – – – – – – – – – – – – – – – – –

Vortex Attack!

With a flying kick Izuku launched a criminal across the street about to crash into a building when someone else shouted from above

"Luna Fall!" Driving the criminal into the ground, a new figure now stood on top of the criminal as the dust cleared revealing a woman with rabbit ears poking out of her head.

Izuku walked up to the scene before crouching next to the criminal, now unconscious. "Jeez, don't you think that was a little much? With the strength in those legs, you could have done some serious damage Mirko"

Mirko smirked, and responded "Nah, I just saved him from flying through a building. But, how do you know me, I didn't introduce myself"

Izuku chuckled, "Rabbit Hero: Mirko, as of one month ago you are the rank 19 pro hero in Japan, known for her agility and strong leg based techniques. Your fighting style is based around your quirk: Rabbit, utilizing your enhanced leg strength, stamina, and instincts to overpower and overwhelm your opponents. You're all over the news, pretty hard not to know of you, especially since not many female pro heroes break top 20, it's very inspiring actually.

"Flattery won't get you anywhere" she said, her smirk widening

Izuku stands up "Whelp, you seem to have this under control, and since you got the last hit you can deal with the press. See ya around" he said with a wave as he started to walk off

"HEY! Get your multicolored ass back over here!" She shouts

"Hm? Is there something you need"?

"Yeah, you. In cuffs"

Izuku tilts his head in confusion "But I'm not a criminal?"

"Oh yeah, then what do you call the vigilantism you've been doing for the past few weeks"

"Being a good person? Besides vigilantism requires I use my quirk, which I haven't been using"

"BULLSHIT! You think I'm going to buy that crap "

"Yeeeees? Because it's true"

"I don't buy that for a second!"

"Ask the lie detector, he's the reason I'm still not in cuffs and will talk to the police when they arrive. His face was hilarious by the way when he saw I wasn't lying"

"Fine then, resist arrest, just means I can kick your ass" she says cracking her knuckles with a grin across her face.

Izuku stared at her for a moment before turning and walking away "Nope, have a nice day"

"HEY! YOU CAN'T JUST SAY "Nope" AND WALK AWAY! FIGHT ME!"

"Why would I fight a hero?" He says staring at her over his shoulder

"Because" she pauses "crap, why would you willingly fight a hero?"

"Yup, so anyways see ya" he brings out the Machine Builder and rides off.

"So I need to give him a reason huh?" She looks at the reporters setting up "Whelp, I can at least make the challenge official"

– – – – – – – – – – – – – – – – – – – – – The Next Morning – – – – – – – – – – – – – – – – – – – –

At school everyone was talking in the classroom over the Kamen Rider fight from the previous day, when Kirishima and Mina walked up to Izuku and Melissa as they entered the room

"Midobro have you seen the news?" Kirishima asked excited

"News, What news? Did something happen" Izuku responded

"YEAH! The Kamen Rider was challenged to a duel!"

Melissa looked at the others inquisitively, "A duel?"

"Yup, Mirko, the number 19 hero, challenged the Kamen Rider to a fight when the press talked to her after they took down a villain"

"Huh, you got it on video?"

Mina excitedly showed her phone "Here! Look!"

"Mirko, was your team up with the Kamen Rider today planned?" A reporter asks

"No, just saw an opportunity to help, is all. After all being a hero is my job, so it is my duty to step in and deal with villains" She responds

"The people want to know, what are the heroes' thoughts on the Kamen Rider? Would you work with them again?"

"If the situation called for it like today, then sure. Their heart seems to be in the right place, but regardless of technicalities they should leave the butt kicking to the real heroes"

"A lot of people say that the Kamen Rider is a hero, what would you have the Rider do then, stop helping people?"

"No, they can help, but they are untrained. The fact that they have no license shows that they haven't gone through any formal training which poses a risk. And sure, they can beat these small time villains, but can we rely on the Rider when a real threat comes, I don't know"

"How could you know then?"

Mirko smirked "Simple, fight me"

"E-excuse me? Fight you?"

"If they can beat me then they are at least as strong as the top twenty heroes right, therefore they can be trusted to handle extremely dangerous situations. So right here, right now, I'm issuing a challenge. YOU HEAR ME KAMEN RIDER! I'LL TAKE YOU ON! SHOW ME WHAT YOU GOT!"

"You've heard it here first folks, the Number 19 Hero: Mirko has officially challenged the Kamen Rider to a duel, we can only wait to hear their response."

The video ended, and Melissa gave Izuku a slight glare before turning to Kirishima and Mina

"Hmm, whelp, I guess we can only wait then and see how the Rider responds" Izuku started "Personally I see no reason for them to fight, so why should they?" he finishes with a shrug

"Mido, where is your sense of awe, imagine it the mysterious Kamen Rider versus the rising Rabbit Hero. It sounds like a movie; I would buy a ticket just to see it" Mina exclaimed

"Plus imagine how manly the Rider would be if he accepts! Then we'd know that they can back up their actions against anything" Kirishima said

"It sounds like you'd think the Rider would win Kirishima" Melissa stated

He chuckled and rubbed the back of his head. "Well, Mirko is cool and all, but the Kamen Rider has been knocking out villains left and right."

"Plus, while Mirko is a pro, the Kamen Rider is like our own local hero! And you have to root for the home team" Mina cheered.

Izuku donned a grin, chuckled "Yeah, well. I personally don't hope they fight, but I'd also want the Rider to win"

– – – – – – – – – – – – – – – – – – – – – – Elsewhere – – – – – – – – – – – – – – – – – – – –

A man walks into an office and says, "You rang boss?"

"Hawks, I have an assignment for you" she spoke turning to face him.

"What do ya need, commissioner?"

"Tell me have you seen the news lately, specifically about the Kamen Rider"

"Oh yeah, didn't Mirko issue some sorta challenge?"

"Yes, we want the Rider to accept this"

"May I ask why?"

"Simple, what Mirko said has some weight. We need to know how strong they are. Besides the only reason they are not a wanted criminal is because of Tsukauchi's testimony that they have not once used a quirk in public, and his testimonies are fact as you know "

"Yup, can't beat a lie detector after all. So, what do you want me to do?"

"Deliver a message" she slides over a piece of paper "Tell the Kamen Rider to accept the fight otherwise they will be labeled an exception to the vigilantism laws and be treated as a criminal"

"What happens if they win"

She smiled "Simple, we talk to them about being a proper hero and add them to our ranks"

"And if they lose?"

"Depends, Mirko isn't rank 19 for nothing, so we will play that path out as we see fit"

"Aye aye, anything else I should know?"

"That is all, dismissed"

Hawks gives a nod and walks out

Another woman in the corner speaks up "What happens if the Rider goes against us then"

The commissioner sighs and responds "Once again it depends, if they can be reasoned with, we attempt to make them stop, if they become a threat, I trust that you can eliminate them, Nagant"

– – – – – – – – – – – – – – – – – – – – – – A few days later – – – – – – – – – – – – – – – – – – – –

Izuku was riding the Machine Builder, with Pirate-Smartphone equipped, on a simple patrol when he heard a voice call out from above.

"YO! KAMEN RIDER! YOU GOT A MINUTE!" Hawks shouted from above

Izuku pulled over to the side of the road and waited for Hawks to land.

"Hawks, current number 11 Hero, how can I help you?" Izuku said

"I wanted to ask you a question, you know about the challenge issued by Mirko"

"Oh that, yeah no thanks. No reason to fight a hero, see"

"Fair, fair" Hawks nodded then sighed "Then I hate to be the messenger bird to deliver ya this" he handed Izuku a paper.

Izuku's eyes widened under the mask "HUH! A criminal if I don't fight a hero, how does that make sense?"

"Simple, the HPSC wants to see your abilities, whether you win or lose you won't be treated as a criminal, only if you don't fight"

Izuku sighed and slumped against a tree "Man, this is the worst. So I either A completely disappear or B fight Mirko"

"Yup"

Izuku sighed again "Alright, but I have a condition"

"Alright shoot"

"If I win, I get a favor from both Mirko and the HPSC"

"Only if you win?"

"Hmmmm, fair point, I get a favor from the HPSC only if I win, I get a favor from Mirko regardless, consider that my fee for her challenge then" Izuku retorts

Hawks sighed "Flew into that one I guess, alright lemme give my boss a call" he then pulled out his phone and explained Izuku's terms, nodding then looked back to Izuku, closing his phone in the process "Alright, but the HPSC favor can't be too extreme."

Izuku stood back up and held out a hand "don't worry, the worst you'd get is a little paperwork"

Hawks smirked and shook Izuku's hand "alright then, where and when"

– – – – – – – – – – – – – – – – – – – – – – Back home – – – – – – – – – – – – – – – – – – – –

"YOU WHAT!" Melissa shouted

"It's not like we had much of a choice Mel"

"Please tell me your "favors" are not going to be idiotic"

"They're not, all I want from Mirko is a sample to make a bottle, and for the commission" He looked around to make sure his mother couldn't hear and whispered to Melissa, her eyes widening and a small smirk grew on her face

"How confident are you?"

"That's why I need you to help me strategize"

"What are we waiting for? We don't have much time; Saturday is in three days!" she said dragging Izuku down into the lab

– – – – – – – – – – – – – – – – – – – – – – – Saturday – – – – – – – – – – – – – – – – – – – – –

A news reporter faces a camera and speaks "Here we are, anticipating the fight that should begin within minutes between the Rabbit Hero: Mirko, and the Kamen Rider, now all we can ask is where is the Rider"

Mirko tapped her foot, impatient "They better show. I want my fight"

An engine could be heard in the distance, as the Izuku approached, donning the Lion-Smartphone combination. He stepped off the Machine Builder, transformed the bike back into a phone and loaded the lion bottle back into the driver.

"Alright, before we begin did the HPSC tell you about my condition for you"

"Yup, one favor, that's easy" Mirko said grinning

"Perfect, I'll collect after the fight then"

"Hoh, confident, are we?"

"Would you prefer me trembling? I'm only here in order to protect my innocence, being a hero would be tough when the law is against you"

"If you want to be a hero so bad then why didn't you go through a school or apprenticeship. I'm sure someone would take you"

"Haven't had the chance to, I'll get to it eventually" he said shrugging

"HAH! Man, after I kick your ass don't give up, you'd make a great hero one day"

"As far as I'm concerned, I am one, I just don't have that piece of plastic saying I'm allowed to help people"

Mirko's eyes widen slightly, her smile growing wider as she starts to laugh "That's a fair answer. But I'm not here to test your resolve, or your morals, I'm here for one. Simple. Purpose. A fight" she cracks her knuckles "so, you gonna run away again?"

"Not this time, plus I didn't run. I rode"

"Well then" Mirko looked over to Hawks who was overseeing the fight "Tell us when ref"

Hawks put a piece of popcorn in his mouth, and shrugged "Alright then, 3. 2. 1. GO!"

Izuku readied his golden blaster, in a flash, Mirko had closed the distance, and was going for a kick, straight to his gut. Izuku attempted to deflect the hit, but she pushed off and gained distance. Quickly pressing the applications on his shield, pulling up a diagram.

"Alright attack plan beta is a go then!" Izuku then attempted to perform a shield bash at Mirko however Mirko intercepted the bash, pushed off the shield again, did a mid-air flip, and shouted "Luna Tijeras!" while falling she managed to wrap her legs around his head, spinning and throwing him to the ground. Before Izuku could reorient himself, Mirko rushed and grabbed him in an attempt to suplex him, before he quickly fired a shot into her leg, causing her to lose her grip. Izuku used this moment to create distance between himself and the hero. Mirko, not missing a beat, threw kick after kick at Izuku, with him barely keeping up until. CRACK. The Build Pad Shield shattered.

"Heh, not so tough without a shield" Mirko stated, continuing her assault, as Izuku attempted to block, eventually getting one parry with his gauntlet, firing several small blasts and gained distance.

Izuku thought to himself She's too fast, not only that, at close range she's too dangerous. My shield strategy has done more for her as a springboard than for my own defense. And with it gone it needs too much time to repair itself. I need a new plan, and an opportunity but how? Surveying his options, he thought of a solution, but he'd need one moment where her constant assault lulled.

"Ready to give up!" She called, a massive smirk on her face

Whelp, ask and you shall receive, I guess. Izuku stood up and responded. "I'll admit, you have the current me on the ropes. Good thing I'm not a one trick rider" He pulled out two new bottles from his belt, and began shaking them, several equations began swarming from behind him towards Mirko, giving her a face of confusion.

"What, are you going to nerd me into submission?" she asked

"No, just hit you really hard. Hope you like debuts, I haven't used this one yet" He pulled the current bottles out of the driver, turned the nozzles of the two new ones and reloaded the driver.

Hedgehog – Lock

ARE YOU READY?!

"Build Up!"

The new frames replaced the previously equipped ones, Izuku's right arm colored white, and covered in spikes, with a spiked ball encasing his hand. Meanwhile, his left arm was golden, armed with a key adorned to his forearm. Tracing his left hand along his spiked white eye he stated, "I have the winning formula"

"So, what you got a new coat of paint, not going to do you any good" She claimed

"We'll see" Izuku rushed at Mirko, he attempted to swing down with the mace that donned his right, she dodged to her right, and attempted to kick his arm, only for him to parry with the key on his left. Mirko flipped back and attempted a roundhouse kick to his head only for him to raise his arm to block.

"Hah, you'll lose an arm here" She smirked

"Nah, you'll lose a leg" He responded, suddenly spikes shot out of his arm impaling her foot as contact was made. Mirko screamed in pain, as she yanked her leg off the spikes. With Mirko stumbling back, Izuku took the offensive, forcing Mirko to apply more pressure to her injured side, eventually causing her to lose her footing. Seizing the opportunity Izuku aimed his left arm, and chains shot out of the key, ensnaring the heroine, locking Mirko in place.

"What the hell!?"

"Told you I had the winning formula" Izuku begun to crank the handle on the driver

VORTEX ATTACK!

Izuku jumped into the air performing a flying kick right into Mirko, with him landing on the other side and an explosion happening in the background.

Mirko stood for a moment, and turned she started to walk towards Izuku, before collapsing on the ground. "Why the hell was there an explosion?"

"Honestly no idea, first time I put that much into one" Izuku shrugged

Hawks walked over and looked down at Mirko "You good?"

"I can't feel my legs, but I know there are holes in one of them. DO YOU THINK I'M GOOD BIRDBRAIN!"

Hawks gasped in mock-offense "Wow, not like you to throw in the towel Mirko"

"Not like I lost to a villain, he just caught me off guard is all. How was I supposed to know they could change suits like that!"

"Fair enough" Hawks then walked over to Izuku, grabbed his wrist, and held it in the air "YOUR WINNER! THE KAMEN RIDER!"

"So, this means I can keep doing what I do?" Izuku asked

Hawks chuckled "Yep, but I do believe we owe you some paperwork now. So, what do you need"?

Izuku smiled, "I'll tell you when you drag me to a meeting with your boss tomorrow, because I know it's going to happen. Pick us up where you met me three days ago". Hawks nodded and went over to Mirko and picked her up. "Oh wait, let me get my favor from her now."

"Huh! I can't really move right now Rider" Mirko questioned

"I don't need you to, all I need is a little blood" He holds up a capture bottle "Kinda like a shot, won't hurt at all and no side effects to you"

"THE HELL?! Why" she asked, Hawks also tilted his head at Izuku

"Hawks I'll explain in depth tomorrow, but the short and sweet is this, I can use your blood to give me an upgrade"

Mirko's eyes widened and a smirk grew on her face "So you'll be stronger next time we meet?"

"Yup"

"Feel free then, you may have won but your fighting skills show your lack of experience, you'll need some of my power to keep up"

Izuku chuckled "that I do, so I graciously accept. Thank you for your contribution. Rabbit Hero: Mirko"

"Keep up the good fight, Kamen Rider"

"Build, I'm the Kamen Rider: Build" he said as he pulled out the Machine Builder, gave a two fingered salute and rode off.

Next episode preview:

Hawks: Hold up who's the girl

Izuku: I said pick us up

Hawks: Fair enough have a nice day, so what do you want

Melissa: Simple we want …

Next Time on To Build A Hero:

To Build a Deal