A means of evolution

I don't own prototype or MHA

Izuku held his stomach lightly he hadn't expected his younger doppelganger to hit him before he could even stand up properly.

He had kicked Izuku in his stomach and forced him away far enough that Izuku had hit some kind of wall but it like the rest of this place was solid stainless white.

Izuku hadn't noticed as his focus was on his uninvited guest but now that he was able actually focus on the terrain around him it was somewhat disorienting no markers of any sort no true means of gauging distance.

A sudden pulse of pain reminded Izuku that he really had better things to focus on thus Izuku stood and turned to face his attacker.

MinIzuku was staring right back a slightly smug look on his face "Are you going to fight me, you are supposed to be a hero and yet you are so behind because of that man that I am going to have to hurt you a bit to catch you up to speed."

Izuku felt a bit of fear creep up his spine what does that mean…on second thought Izuku didn't want to find out so he focused on the only transformation that he could use.

Izuku's arms shifted and squirmed before sinking back into his flesh unveiling his overly muscled limbs…he got the feeling that it was the wrong choice as MinIzuku smiled sadistically and his smaller arms began to writhe before sinking away exposing sharp and shiny claws.

Izuku swallowed and attempted to speak "I-I don't thin-!" however before he could finish speaking a set of claws were inches from his eyes.

Izuku barely managed to raise his arm enough to prevent his face being skewered but in doing so Izuku took the attack to his arm and the wound was gushing bright red blood.

There wasn't blood the last time he was stabbed what was going on?!

MinIzuku's smile grew even wider as he spoke "I have rendered you unable of passively healing yourself you will not die but pain shall become a good acquaintance and you will be required to learn how to dodge and how to use the other basic shifts."

Izuku looked on confused shifts he couldn't stop himself as his eyes drifted to his arms is that what these abilities were called?

Again MinIzuku spoke "Yes I call them shifts but each shift has a specific name the one you are using currently is called musclemass it is purely a strength based ability you probably unlocked it due to your fascination with that skeleton of a man."

Izuku frowned at the slight insult to his mentor and spoke "I how do I unlock new 'shifts'?"

MinIzuku's smile became a bit more playful as he replied "How did you unlock the first one?"

Izuku narrowed his eyes in thought what was he doing when he gained musclemass…he was worried about his attacks without one for all…he wanted it but that couldn't be it right there had to be more to it than wanting it right this wasn't some anime or manga there had to be more to it.

Again Izuku found himself under attack only this time instead of the three semi-jagged claws from before it was a single blade about as wide as his wrist and just like before Izuku out of instinct raised his arm in defense.

However, unlike before the far taller and thicker blade cut right across his face and right through his arm cleaving it from his body.

The appendage fell to the ground with a thud and faint drip as the blood in the limb splashed out and Izuku screamed in pain as he fell to his knees.

MinIzuku let Izuku scream for a few minutes before he seemingly got bored and picked up the severed limb and began toying with it.

Eventually Izuku stopped screaming and with tears still fresh in his eyes as he looked to MinIzuku in betrayal and pain.

The miniature made a slightly disgusted face and spoke "I turned off your ability to feel pain 30 seconds after I severed it."

Izuku took a shaky breath whilst still clutching his stump he went to stand but failed and fell back to his knees too shaken to stand properly.

MinIzuku's face lost a bit of its edge and touched Izuku's face gently with his free hand "I know that it hurt and I know that you probably feel a bit betrayed but its best that you get used to pain here where you can't die…and you were right the first time it is desire however you do need to shape it, imagen it in detail, mold it to your liking."

After a moment Izuku asked a question "W-why so suddenly why d-do that?" as he finished Izuku looked to his arm.

MinIzuku frowned and raised an eyebrow "This is a part of the whole catching up thing your pain tolerance is good because of your 'friend' and his friends but it needs to be better if you are going to be fighting people that can and are going to try and kill you."

Izuku flinched he knew who his miniature was talking about…but before he could dwell on it MinIzuku held up the limb and spoke "Now this bit is going to be useful to know so focus."

MinIzuku pressed the severed limb onto Izuku's stump and held it there "Now heal it, reattach it."

Izuku flinched as the feeling of his cooling flesh was pressed to his still bleeding stump and his mind raced how could he do this, could he do this?

MinIzuku bonked the back of Izuku's head strongly somewhat clearing the thoughts from his head and then he spoke clearly and strongly and in a tone that definitely wouldn't have been coming from a young Izuku "You can do this and so much more."

But It gave him the courage he needed to think to of how, not if he could, do this reattach his limb and so he began to think.

He thought about his quirk completely missing the slight frown that flashed across MinIzuku's face before it vanished as his limb and stump grew tentacles that interweave with one another and pulled the limb back to the body connecting them and making the wound seal and heal near instantly.

After a solid few minutes staring in awe Izuku began to have thoughts and a few questions for MinIzuku and eventually Izuku came to a conclusion, his quirk didn't really fit any known category it could take in other quirks, not just copy them temporarily, but completely have his own version, if mutated to a degree, and he hadn't seen any other abilities from MinIzuku but MinIzuku claimed that his base quirk also boosted his regeneration, strength, speed, agility whilst also giving him the ability to take not just the quirk of someone but their appearance and memories.

However, Izuku's awe was quickly curbed when MinIzuku informed him that he would have to consume the brain to get the memories but everything else could be gained through no less than a single cut which made Izuku freeze again as his thoughts flashed back to his oh so recent guest.

MinIzuku however didn't take to kindly to the distraction and whacked him again "Focus imagen how it would look."

After a deep breath to clear his thoughts Izuku thought of his transformations his shifts the writhing tentacles and just like that Izuku knew what it would look like and the odd stretching and wiggling sensation that he had associated with the shift to his musclemass.

Izuku looked down just in time to see the last faint line across his arm disappear in a web like weave as the last of the tentacles sank into his now reconnected arm and he felt a wide smile grow across his face and he turned to see MinIzuku giving him a small smirk.

And cut