With alarms blaring wildly across the campus, Bakugou books it back to the observation room where the rest of the class are. With the incident with Deku leaving him unconscious for the time being, it's up to him to take control of the situation. Bursting through the door, he's greeted by the business end of an Ak-47 courtesy of Momo who puts it down after realizing it's him. Immediately upon seeing Izuku still out on his back, the class gathers about to try to figure out what the hell just happened.

"We don't have much time, Ponytail make a smelling salt to wake this idiot up and if he doesn't wake up, slap him until he does." Katsuki orders prompting Momo to create the small white packet. Bakugou shakes it a few times before snapping it in half under Izuku's nose but this accomplishes nothing. "Fuck. He's gonna be out for a while, just what the hell did you extras do anyway?"

"We didn't do anything, in fact we couldn't even get close to him, he suddenly grabbed his head in pain scratching himself violently before putting his hands on the ground and the whole place started turning to dust." Shoji explains as Katsuki drops Deku onto a chair beside Ochako and Eri.

"Fuck it we'll figure this out later. All Might, stay here with Aizawa and the rest of my class to protect ShigDeku or whatever the fuck he is now. Nana, Endeavor, Half n Half, Sparks and the rest of you pros come with me. We need to find and kill the shitbag that got on campus."

"Who put you in charge exactly?" Miruko asks, putting a hand on her hip and scowling at Katsuki.

"Listen here, Conny haunches." Katsuki says pointing at Miruko and scowling harder than she is at him. "I'm the only conscious All for One user right now so we can argue about this shit later after we deal with the villain and whatever other freakbags that came along for this invasion." Miruko returns the glare for a moment before smirking.

"I like your style, kid, let's go kick some ass." Miruko responds before Katsuki and the others sprint out the door.

"Yaoyorozu, can you create a new door and a fortification for it and the wall?" Aizawa says in his monotone yet calm voice. "Create some ear protection for everyone and a blindfold for Eri. She doesn't need to see this."

With a nod to Aizawa, All Might leaves the room and stands guard outside of the door. The much younger, healed and vastly more powerful former number 1 pro hero stretches briefly before rolling his shoulders and flexing his muscles. Feeling the familiar power of One for All course through him like a raging inferno, vastly different to the lukewarm embers that he had tended to for so long. With the fire that had been started by Endeavor and Shouto off in the distance, All Might steps into a boxer's stance and cocks his arm backwards. With a turn of his hip he extends his arm putting his full power behind that punch and the largest shockwave he had produced in over 20 years is ejected from his fist thanks to the power he was granted by Nana all those years ago. The wall of air flies at the speed of sound smothering the inferno thanks to the dust kicked up by the single punch. Watching as the fires now smolder out due to the choking dust and debris he had sent towards it, Toshinori clenches his fist recognizing that his power feels equivalent to, if not greater than what he had in his hay day. Looking up from his hand for a moment he sees something off in the distance. Slightly shrouded by the smoke, a human male stares right at All Might, his four arms are adorn with serrated claws dripping in blood. From this distance All Might couldn't tell if it was the man's own blood or of someone else. Rolling his neck and then shoulder All Might takes a few steps forwards issuing a challenge to Overhaul.

"Only a fool would take in the spawn of his nemesis and indoctrinate him to become his successor. How long before the boy succumbs to his own sickness, his lust for power will be his undoing." The guttural growling voice of Overhaul echoes from within the smoke. "I know not why the world idolizes you, you're just a fool prancing about pretending to be a hero. You were once cleansed of any of these disgusting quirks. A pure human, but you gave that away... for what?"

"Tough talk coming from a bird themed supervillain," All Might says, waiting for Overhaul to step out from the smoke and into view. The olive tinted skin that used to cover the supervillain is now bloodstained and corrupted by the Nomufication process he had undergone. Veins that bulge under his skin ebb the surrounding area in the same charcoal black tone of the high ends that the mad doctor had created. "So. You're that punk I've heard about." The former symbol of peace flexes his calf muscles and releases a shockwave from his legs as he cracks his knuckles.

"You're apprentice was the one to face me before Eraserhead shot me in the head. I'm sure you're aware of what my powers are... suffice to say I've been enhanced in a way since then." Overhaul explains as the flesh that surrounds the additional arms that sprout from his back begin to contort and shift into serrated spears.

"Yes yes I know. You're a 'touch it you die' type of villain. How about we skip to the good part shall we? Now before I punch you in the schnoz I have one thing to say." Overhaul cocks his head to the side, opening the beaked mouth and sprouting razor sharp teeth from within it. "I've faced my fair share of villains, some more pleasing to look at than others, but you take the cake for the ugliest villain I've ever had the displeasure of seeing."

Dashing to the side, All Might wrenches a manhole cover off the ground before spinning like a discus thrower and frisbeeing the 80kg metal plate towards Overhaul beginning the fight. The steel discus clocks Overhaul in the teeth as it breaks the sound barrier, splitting through the back of his throat and embedding itself in the tree. The flesh that was severed instantly latches back to itself as it heals. Two of the arms that sit on Nomuhaul's back leer down and make contact with the ground a field of spikes erupts from the ground headed for All Might. The former number 1 pro hero smirks before raising his right leg far above his head and slamming it onto the ground in an axe kick creating a massive shockwave that shatters the concrete and reduces the spikes created by Nomuhaul to dust.

With the dust settling Nomuhaul's eyes flash a golden light for a moment before All Might sees something out of the corner of his eye. The normal set of eyes splits from two to four with the arms on Nomuhaul's back splitting from the point between his middle and ring finger all the way to the elbow. The visceral tearing of flesh and snapping of bones echo through the battlefield as blood drains from the new wound. The flesh heals forming two new additional hands attached to a single elbow on both arms on his back. All Might looks on with disgust as the new arms continue to split down Nomuhaul's back before another version of the nomufied Overhaul births itself from the viscera of the first one. Its exposed brain and charcoal black skin reminiscent of normal high end nomu is stained a deep brownish red due to the decaying blood that coursed through the other nomu's veins. "Of course this had to turn into a gank fight." All Might grumbles as the second nomu stands to its full height, its arms splitting to form an additional two limbs. The beaked mouth filled with gnarled, decayed and jagged teeth, the beak reminiscent of the USJ freak show that All Might had fought earlier this year.

"You will not stop us from reaching the brat." Nomuhaul declares as the blood that dripped from his back melts the concrete beneath him. "You should have stayed in retirement, old man." the former hissaikai leader threatens before placing his hands on the ground causing the surrounding area to quickly turn to spikes. The additional limbs on his back turn to black slime and begin to pool around the contorted rebar and concrete. The cement seemingly dissolves into the ooze before being retracted into Overhaul's body calcifying it in a stony armor. Twisted rebar is overhauled to form sharpened dagger-like tips that attach themselves to Overhaul's hands and cage his face like an unholy mask.

"You are one... ugly... mother fucker." All Might mumbles to himself before clenching his fists preparing for his opponent to make the next move.

Faster than a normal man could blink, both versions of Nomuhaul blitz towards All Might. The true form of the arch villain raking his steel tipped talons towards the former hero while the other scrapes its hands along the floor turning it to quicksand trying to trap him. All Might bends almost all the way backwards causing the first Nomuhaul to miss the attack, barley cutting the spandex around his chest before he starts sinking into the ground. Thinking quickly he grabs the metal post of a nearby stop sign in ground theta to wrench himself free of the quicksand created by the false overhaul. Seeing his opponent sprinting towards him, All Might yanks the sign from the concrete leaving a stump of cement and rebar attached to the bottom of the sign before swinging it at the clone. The edge of the stop sign connects with the crevice of the exposed brain in the nomu before bisecting the beast the rest of the way vertically. Seeing a bit of movement from the corner of his eye, All Might follows through the attack on the fake version and spins to face the real one.

"I think it's time for you to STOP!" All Might declares, spinning the sign and delivering the mother of all uppercuts with the concrete stump of the stop sign. The sheer force of the impact is enough to forcibly decapitate Overhaul, ripping his head off the nomufied shoulders. The spine of the nomu tears out of its flesh and reattaches to Overhaul's head before it begins to retract and regenerate the wound the rest of the way. Seeing this as an opportunity to put the villain down for a few moments, All Might grabs Overhaul by the ankle before swinging him over his head and slamming him into the pavement using his full power to do so. "Baltimore. Smash!" He declares yanking overhaul out of the crater that was just created with the nomu's face, and slamming him flat on his back into the concrete once more. Contending with the first nomu takes his attention away from the second allowing the other Overhaul to attack him. It rears back on it's left side before throwing a punch with both of it's left arms, the muscles contort and flex bulging to ten times their normal size before the impact sending All Might flying backwards away from the cloned nomu.

"Even you can't take a punch from your own power." Overhaul declares standing from the splattered mess he just was, his body continuing to regenerate. "I'm sure you're familiar with that quirk considering who used it before you the first time. However the great doctor increased the strength of the impact recoil quirk now dishing out twice what was put in."

"Interesting, I was curious why I felt a bit of pain just now. I pack quite a punch don't I?" All Might states, wiping a bit of blood from his mouth. The force of the strike had sent him flying into the small forest that surrounds site theta proper. "I'm happy that you've decided to take this fight seriously... well I wouldn't exactly call this fighting, more flailing angrily."

"Insolent wretch. Every single hero is the same, an arrogant abomination." Overhaul snarls.

"Clearly you haven't looked in a mirror recently." All Might responds before both versions of the Nomu charge at him. The smile on his face widens as the two get closer, grabbing an oak tree by the trunk, he wrenches it out of the ground before smacking both nomu with it simultaneously. The sheer force of the strike shatters the oak wood into millions of splinters that shred both Nomu into ribbons.

"It's going to take a lot more than that to kill me. All Might."