"Hello?"

It was a young voice, male, and all heads turned to the door. Most of them carried quizzical looks. Bakugo couldn't turn to see the door because he was still shackled to the concrete. 

"Who the hell is that?!" He got an answer right away.

 "This is Pizza-La Kamino, here with a delivery?"

Y/N didn't seem surprised, clicking his tongue and moving his hand around idly while speaking. "We're underground, in an abandoned warehouse. You think it's just a pizza guy waiting outside our door?"

There was silence, and Spinner got up from where he was sitting, walking over to the door.

"We didn't orde-"

"SMASH!" 

There was a tremendous crash, and the wall caved in. Splinters of wood and debris flew across the room, a cloud of dust making Bakugo cough slightly. 

All Might flew straight through, nailing Spinner in the face with a hefty punch and sending the surprised lizard flying across the room.

Shigaraki looked across at Kurogiri, face twisting in sudden panic. "The warpgate! Open it!"

He was cut short as wooden appendages snaked in through the gap All Might had created, binding most of the villains in thick ropes of hardwood. The number four hero Kamui Woods entered after, the bindings coming from his arms.

Dabi attempted to use his fire, but was kicked in the face by a yellow and white blur that sped into the room at Mach 3. His eyes rolled back and he collapsed, where he was restrained.

Y/N just sat calmly there as in an instant, his associates were bound. He had a bored look on his face, and idly wiggled his fingers.

Staring All Might in the eyes.

"So, All Might. Decided to pay us a visit?"

The number one hero snapped his fingers at Kamui. "Why is he not restrained?"

"He's a kid, and a U.A student!"

All Might shook his head. "He's Y/N, the Angel of Death!"

A moment later, another wooden rope shot from Kamui Woods' arm, wrapping Y/N tightly around the chest and squeezing his arms against his sides.

"Don't struggle, it'll get worse." All Might stood close to Y/N. "So, young Y/N. What are you doing here?"

Y/N felt a growing pain in his injured arm from where it was pressed against his side. "Can you loosen the bindings? I've got an injury, and that hurts."

All Might probably shouldn't have, but he nodded at Kamui, and the bindings loosened a fraction. Y/N sighed. "Much better."

"My question."

Y/N slumped slightly in his bindings. "I'm a contract killer, not a hero. What other answer do you need?"

"I thought you didn't have any association with villains? You've killed many of them too."

Y/N's face hardened. "They saved me from death."

"How?" All Might looked thoroughly confused.

"Mandalay attacked me. If you would loosen my bindings on my right arm, I could show you." Y/N had no ulterior motives with this - he genuinely wanted to show All Might that his precious heroes were just as bad as any villain.

New bindings worked their way under his armpit, and the ones around the boy's right arm released it.

Y/N couldn't move it anyway, so there would be no point in trying to escape. "Roll up the sleeve."

All Might carefully did as he asked, not touching Y/N's hand, and moved the shirt's material all the way up to his shoulder.

"This was Mandalay's doing. My arm no longer works due to muscle damage, and I'm going to have permanent scars." Y/N watched the number one hero as his face faltered slightly.

"That would be necessary - you threatened the safety of the camp."

"Oh, so if heroes do it, it's necessary, but if a villain did it, it would be illegal."

"We have reasons!" All Might was on the defensive now, and despite being restrained, Y/N smiled.

"And using me as an excuse is a dick move by the way. I had no involvement in the planning of the attack."

"How were we supposed to know that?"

Y/N met All Might's eyes. "You said it yourself - you didn't think I was associated with villains."

The man's face tightened and he turned away.

A slow grin spread onto Y/N's face, and he looked innocently at the wood that restrained him. "Hey, this is connected to Kamui right?"

Kamui looked at him, surprised. More heroes came into the room, as well as a small army of police armed with huge machine guns.

"So if I drain this, what will happen?"

Before anybody could act, Y/N's hand wiggled slightly, stretching to tap the wooden bindings.

They shrivelled and died, falling off him, and Kamui's eyes widened as the wood started to die right up to his arm.

All Might jumped for Kamui, breaking his wooden arm to stop the death from reaching Kamui's chest. The wooden hero shouted in pain, and All Might tossed aside the dead branch.

Y/N smiled, eyes glowing purple. "And now you're fucked."

He dodged a blow from some random old man moving ridiculously fast, grabbing the man's ankle and tossing him at All Might, where they collided.

A few of the police opened fire, and Y/N just stood there as the bullets hit his cloak, playing out their kinetic energy on its enhanced material and falling to the ground smoking.

One went straight for his face, hitting his mask and literally shattering into dust. How strong did I make that dust stuff?

Y/N went for his knife as All Might got up, drawing it in one smooth motion and tossing it at one of the police officers.

They were wearing full protective body armour and thick clothing, as well as riot helmets made from reinforced plastic, but the knife hit the unfortunate officer in the neck, ripping straight through the plastic protection and burying itself in the flesh.

It cut through the officer's neck easily, detaching his head in a gory spray of blood and going through the wall. Ew. 

Y/N pulled it back to his hand, teleporting to another two officers and draining them before they could react.

All Might attempted to stop him, but Y/N formed the dust making up his mask and the knife into a long spear, keeping the hero at bay as he disposed of another two police.

"Don't you realise you can't stop me?"

He cut the bonds of his comrades, not caring that two of them were unconscious.

Shigaraki quietly asked Kurogiri to open a warpgate again, but what looked like a flying straw flashed across the room, burying itself in the mist man's chest and making him slump.

"Did you kill him?" Y/N glared at All Might, and a hero materialised out of the straw. His face flickered like a faulty TV for a second, and he returned to the rest of the heroes' side.

"No, just messed with his insides and put him to sleep."

The heroes had grouped up on one side of the room, and the police besides the dead four were arranged in ranks behind them.

Y/N stood between them and the vulnerable villains, clutching his spear menacingly in his working left hand. Nobody wanted to try to attack him.

"Hey, you think your master can get us out of this?" Y/N looked back at Shigaraki.

"I could definitely escape by myself, but I couldn't take anybody with me. So, can you create a distraction or something?"

Shigaraki shook his head, and Y/N noticed his hands were shaking horribly, still in their artist's gloves. The white-haired man was breathing rapidly, eyes flickering from hero to police officer and back again.

"Are you okay?" The boy ignored the enemies standing metres away, heading to Shigaraki and grabbing both his hands, dropping his weapon.

"Just take some deep breaths, yeah? It's not the end. You're fine."

The man's shaking subsided slightly, not stopping though, and Y/N sighed. "You want a hug?"

His shaking immediately stopped and he shook his head no. "I'm good." The part of his face viewable through the hand stuck on was a bright red.

"What the hell?" That was the man that had come from a straw.

Y/N straightened his back, staring at the hero disapprovingly. "It's not just heroes that have mental challenges to deal with, you know."

He strode towards the group of police and heroes, face hard. "Don't just assume so-called villains aren't people."

They took a collective step back, and Y/N was about to advance further when grey sludge dripped down in front of him, making the boy stop in surprise.

The walls were coated in some weird goo, the sludge stuff forming into ovals that looked much like Kurogiri's warp gates.

Shigaraki's eyes went wide. "Master."

They formed in mid-air, and some weird creatures with exposed brains and four eyes poked their heads out, screeching and growling in high-pitched voices.

Shouts started to ring out from both inside the room and outside.

"Nomu!"

"There's so many of them!"

"Fall back!"

"Get Endeavor in here too!"

Y/N looked back at Shigaraki happily. "Is this whoever you work for?"

"Yes." Shigaraki was staring blankly at the grey sludge. "Master."

More grey sludge started forming around each of the League's members, including the unconscious Dabi, and they started slowly sinking into the pools.

Y/N glanced at the heroes. They were being swarmed by the weird monsters, screaming and shouting as they blasted them left and right. 

Shigaraki began sinking into a pool of his own, and held out his hand for Y/N. "Jump in here. Master will help."

Grabbing his spear off the floor with his good hand, Y/N did as he asked without using the offered hand, jumping into the grey pool that had formed around Shigaraki.

The momentum carried him much faster than Shigaraki was sinking, and he fell right through the goo.

His head passed through with a small moment of panic as he couldn't breathe, then he was through, falling on something hard.

Gravel crunched beneath him, and he swore loudly as he heard a man's deep voice.

"Who is this?"

----------------------------------------------------------------------------

Y/N sat on the ground with a pool of grey sludge above him, staring up at a huge man wearing a ridiculously expensive suit.

It looked like it had been custom made to fit his massive frame, but still fitted him poorly, hanging loose in some areas and especially bad-looking around his neck area.

He was wearing some sort of helmet, and Y/N couldn't see his face, but the boy felt something about this man that was different to any other villain or hero he'd seen before.

Maybe it was the fact he was levitating.

"I, uh, I'm Y/N." He didn't know why, but there was something inherently different about this man that made his heart pound faster and his hand clench around his spear.

Shigaraki fell out of the grey goo, landing on top of Y/N and groaning in pain. "I always hate that..." He muttered, getting off the startled boy.

The man spoke in his deep voice. "Shigaraki Tomura, who is this?"

The white-haired man dropped to one knee in front of the huge man, bowing his head in respect. "He's a new recruit. The Angel of Death."

Shigaraki spoke, and there was an unmistakable emotion in his voice. "Thank you again for rescuing me, master."

The large man slightly tilted his head while ignoring Shigaraki, the front of his mask angled towards Y/N, but it didn't feel like he was actually looking at the boy.

"Interesting quirk."

Y/N got off the ground, backing slightly away from the imposing figure. His eyes glowed purple, and he held his spear in a defensive position.

"All for One, this is not a quirk that you should take."

A shock ran through Y/N, and he backed away another few steps. Take?

Shigaraki continued speaking, still kneeling. "It would render most of the other quirks you have taken useless, and interfere with your brute strength."

"Killing with a touch... Extremely useful."

"Most of the quirk's abilities focus on movement and evasion, and are only activated after draining life. Which means it is an extra inconvenience for you."

Y/N stared up in mute fear at the man Shigaraki had called All for One.

The man sighed. "I will hold off on taking it for now. If he is valuable, then you do as you see fit."

"Thank you, master."

Shigaraki straightened, turning to Y/N with a small smile on his face. "This is... All for One."

"Who?"

"Insolent boy." The man extended his arm, red and black electricity flickering around it, and his arm grew in size before a shockwave erupted from his hands right at Y/N.

He turned translucent to watch the attack go straight through him, demolishing a building behind him.

"I'm not being disrespectful! I genuinely don't have a clue who you are!"

All for One huffed as Y/N turned solid again. "Just as All Might is the Symbol of Peace, I am the Symbol of Evil."

Y/N nodded sincerely with a wide-eyed gaze. "What are we here for?"

"I thought you needed help."

"Yea... But what do we do now."

Y/N noticed where they were for the first time. Several pro heroes were lying dead or unconscious on the floor, one that Y/N recognised as Best Jeanist with a gaping hole in his chest.

They were in the ruins of some warehouses, but the surrounding few buildings were also destroyed, absolutely smashed to dust. Broken bodies of police officers were strewn everywhere, and Y/N whistled in appreciation.

All for One strode towards Shigaraki.

"You have failed again, Tomura. But do not be discouraged."

"Try again. I have brought back your associates as well." He gestured around, and the rest of the League fell out of their own grey sludge pools.

There was silence for a few seconds, then Bakugo fell out of his own sludge pool, attached to the concrete block.

Y/N had forgotten all about the boy, and as the concrete fell to the ground, it broke into pieces, releasing Bakugo.

The young boy was oddly unaggressive. Perhaps he realised how deep in shit he truly was.

All for One held up a hand, and everybody froze.

"Ah. He's here."