The initial expectations of the USJ were shattered upon arrival, no one was there and the place appeared to be in shambles as if used to test weaponry with no regards.

"Hold on, didn't you say someone else would be here, sensei? And what the hell happened, this place is in ruins!" Eijiro exclaimed upon wandering forward slightly, held back soon by Aizawa himself who stepped forward for the sake of getting a better vantage point.
"Something's not right, the security should've kicked in if something happened." he said blatantly, scanning the surroundings for anything, "Wait here, I'm taking a closer look."

From there, Aizawa descended the stairs while keeping himself on high alert. Any Villain that could do this so seamlessly is dangerous, students shouldn't fight that.

Reaching the bottom of the stairs, there seemed to be no one. Not a single sight of movement aside from the occasional debris that lost its footing and fell. A deafening silence that shouldn't be present roared over the USJ, a sense of danger loomed clearly yet no sign of danger itself.

The biggest shock came in the form of what appeared to be shards of glass, accompanying a shattered mask that looked familiar, a little too familiar.
Picking it up, he realized just what it was and made way to head back.

It didn't take long for a Pro-Hero to track back and reach the students anew, with a sigh he confronted the students and told them what they'd be doing, "Class is cancelled, I don't know what happened here but you kids are at risk here."

"Come on! I was looking forward to this!" Eijiro exclaimed in regret, which led other students to chime in on the topic, "I think it's better to do as he says, this place was likely attacked recently, ribbit."

"I agree!" Ida began, "And if the attack was recent, the Villains might still be near. Class President, what do you think?"

Izuku stared back, then looked at Momo who was already staring at her, the choice was clear if everyone's safety had to be ensured. The two nodded to each other.
"We should do what sensei said, it's dangerous here."

Everyone experienced the sense of dread in another way, while some pushed it to the side.
Tanjiro however, was the most on edge. The smell that lingered through the USJ was familiar to him and he knew all too well what that rotten and sour smell meant, it lingered somewhat on him aswell afterall.
It left a feeling he couldn't shake, causing him to look back several times as everyone was leaving.

Yet they weren't allowed to. A sudden mass of black and purple blocked the entranceway leaving it an impossible route.
A few steps back led to the first 'visitor' to arrive, a man covered in hands, hair white and unkept, bringing forth a sense of unhingement that gave him a presence of danger. But he wasn't the danger.

He was far from the danger.
"Finally, you're all here. You took longer than expected, and you call yourself a Pro Hero?" he spoke, resisting the urge to scratch his own neck as he pulled out a recorder from a pocket, Aizawa was on edge and ready to engage, logically. Signalling for the students to retreat he stood there, confrontational.

Yet the Villain didn't attack, he pressed a button on the recorder and a pre-recorder voice emerged, speaking a simple command. "Kill the Heroes."
"Annoying, how this thing only responds to his voice. I just hope that 'Lower Moon' comparison of his means something good."

Responding to the voice of the recorder, a large black muscular humanoid exited the portal behind the Villain, it's face almost resembling a beak filled with sharp teeth, stuck in an eternal angered grin. Eyes bloodshot, slitted, filled with bloodlust that knows no friend. The remnants of clothes on it's body hid the strange tattoo-like lines that spread downwards from its neck like a blooming flower.
It's voice was deep and distorted as its teeth crunched each other before repairing themselves on the spot, simply bellowing a declaration to "KILL."

It rushed forward while the students backed off, hiding themselves away at the center plaza for now. The crash of its fist meeting ground bellowing ahead while debris flew wildly.

As a Pro-Hero, you protect the innocent. Therefore Aizawa had the task to protect his students, a task he was not willing to fail, not now not ever.
He put on his goggles, and readied his cloth. Charging the opponent while canceling it's Quirk, striking it repeatedly with the cloth and entangling it's arms, pulling it to the floor.

Yet it resisted, it lifted its arms and swung them wildly, throwing Aizawa back.
Nearly falling down the stairs, Aizawa stood back up.
His phone rang at the right time, yet he had no chance to pick up.
He atleast read who was calling, it was All Might.
He tossed his phone at the students, yelling "PICK IT UP." at them before dodging another blow from the behemoth sent after him.

It was thanks to Hanta that the phone was recovered quickly, and it was logically given to the Class President to pick up.
Izuku did.
"Aizawa, I might not be able to make it today-" All Mightbegan before being cut off, "This isn't Aizawa! He's fighting a giant Villain right now, the USJ is in ruins!" Izuku spoke, not wasting a single moment to deliver the clear message.
There was a silence on the other end, it was clear All Might was contemplating it. But then he spoke with a soft tone, "Midoriya, protect the others. I'll be on my way." before the phone was hung up.

It seemed a simple task, to keep his classmates safe with the same power All Might used to keep Japan safe, yet he was proven wrong as another mass of purple and black swirled into existence before them, taking a humanoid form after with piercing yellow eyes. Slits formed within by the simple absence of yellow.
He did not speak, he did not move. He was simply there to stall them until the behemoth could finish off Aizawa and continue on with the next.

He raised an arm, creating more swirls from it that quickly consumed the students with no chance to react.
By the time they could see again, the students had been separated and sent to the various areas of the USJ. Swirls appearing before them to release Villains in mass quantity, this would be a fight of endurance.