The Downfall Hero

Chapter 1

Izuku follows the skeletal man, Toshinori Yagi (if his ID was to be believed) to a Dagobah beach near his house, hidden behind piles of junk. Izuku notes the disgusting state of the beach. Turning to the middle schooler, the blonde smiles, and Izuku can't help but think that it seems familiar somehow. "Listen, this is a very big secret, so don't go posting about it online." In a puff of steam, the walking skeleton was replaced with the massive figure of All Might.
Izuku crosses his arms, unimpressed. "How do I know you're not a shape-shifter?"
The alleged hero lets out the iconic laugh. "A very perceptive young man. That's a good quality for a hero. All right then, if I was a shapeshifter, could I do this?" He taps a washing machine nearby and it crumples like cardboard.
With evidence that this was the unstoppable hammer of justice, Izuku got stars in his eyes. "Holy crap you are All Might!"
All Might laughs once again. "Indeed I am All Mi-" he is cut off by a tsunami of blood and a cloud of steam.

After cleaning up the red mess, the deflated hero was left to explain. "Anyway, I'll cut to the chase. About five years ago, I got into a fight with a pretty nasty villain, gave me this." He lifts up his shirt to reveal a massive scar on his torso. "The surgeries removed most of my respirator system and my stomach, leaving me with only three hours a day of hero work." He drops his shirt. "But there is a simple solution. My quirk." Izukus hand twitches with the urge to grab a notebook. There is no confirmation on what the number ones quirk actually is, but this was clearly serious. He'll just have to commit what he can to memory. "The truth is, this quirk was not originally my own. It is a scared torch that was passed down to me by another. The name of my power, is One For All. The first user cultivates the quirk, then passes it down, growing stronger with each generation. With my worsening condition, I began to look for a worthy successor, and you, young man, have proven to have the heart of a hero. Now, this is a secret that must be protected. Should a villain discover the true nature of my power, there will be hoards of those who wish to take it for themselves. Can I trust you with this sacred torch?"
Izuku's expression hardens. "I won't tell a soul."

He runs up the stairs if his apartment building to his best friend/neighbours door. "Kacchan, I have a secret to tell you, Kacchan!"

After relaying everything All Might told him, Kacchan just looks at Izuku blanky. "All Might is retiring?" Izuku nods. "And he wants to give you his quirk?" Another nod. Kacchan blinks slowly before sighing. "Guess I can say goodbye to that number one spot."
Izuku waves away that statement. "Please, my quirk makes me look like a monster from a pre-quirk movie. I doubt I'll be popular enough to make number one."
Kacchan just deadpans him. "You get tougher the more you fight and you're about to get a quirk that lets you level mountains. If you don't make number one, I'll be disappointed in humanity."
Izuku shrugs. "We'll see. Anyway, he wants me to start training tomorrow. I was thinking of training Evolution as well by getting you to blow me up."
Kacchan smiles ferally. "Can't wait."

The next day, Izuku is struggling to pull a fridge with All Might sitting on it. "Pretty nice view up here. A little too static in my opinion though."
Izuku throws the blonde a dirty look. "Maybe that's because it has an extra 280kgs sitting on it."
All Might just laughs. "Nah, I'm closer to 250 these days."
Dropping the ropes, Izuku looks up at All Might. "Why am I dragging this trash again?"
"Because your body is an ill-suited vessel for my quirk right now. Do you have any idea how much power is stored in this quirk after eight generations? Your limbs would pop off."
"My limbs!? I've heard of backlash but that's ridiculous!" Calming down, Izuku looks around. "So I'll be training different muscle groups by hauling trash."
All Might nods. "Well, yes, but not only that. Before I explain, I have to ask you a very important question. You have the heart of a hero, but what drives that heart, what is the focal point of your desire to be a hero?"
Izuku thinks hard about that question. He never considered it before. "Because I want to be like you." Before All Might can ask him to elaborate, he continues. "And I don't mean rich or famous. I want to be a hero that helps as many people as he can. I know a hero can't be save everyone everywhere, that's just unrealistic. But I want to be the kind of hero that gives it his all to save everyone he could ever hope to save, and to ward away the ones that would hurt them"

All Might's already massive smile widens even more at the answer. "Then consider this as your first deed as a hero. I did some research and this beach has become a dumping ground. The current drags in trash from the ocean, and the more irresponsible locals dump even more of it. Its the small things that make a big hero, so my proposal to you is to clean this entire section of the beach before the entrance exam." He compresses the fridge he was sitting on, the air pressure pushing bits and pieces away from him. "And restore the view of the ocean." Izuku nods resolutely before rapidly picking up trash and hauling it into a truck All Might brought with him.

Izuku was exhausted. He cleaned almost non-stop for hours. Not to mention giving his mom the food list for All Might's aim-to-pass-American-dream-plan. But there was still one thing he had to do before he could rest for the day. And it was going to suck. "All right! Let's do this!"
"You're weirdly excited for this."
Kacchan just grins at him. "Consider this payback for ditching me with those thirsty ass extras." Sighing, Izuku transforms, his skin turning a dark grey, hair turning white and bone like nubs emerging from various points of his body (elbows, forearms, shins, knees, chest, jaw, knuckles, shoulders and the ends of his fingers). They weren't exactly shape, but they were the closest thing his body had to armour in this form.

Name: Izuku Midoriya
Quirk: Evolution
This quirk makes us a transformation that stockpiles his experiences in order to adapt. If he gets hit, he gets tougher, if he gets burned, he gets fire resistant. Think Darwinism on fast track.

Izuku sighs for the third time that day. "Get it over with." With a psychotic gleam in his eye, Bakugo unleashes explosion after explosion in his best friend.