Gray looked at Mirko for a few seconds before he said, "Sure, you can join too. I wanted to test something anyway."
Before anyone else could speak, Gray turned and walked out of the training facility. "Give me a second. I have to speak with Nezu real quick."
Gray walked back to the administration building and knocked on the principal's door. "Come in," he heard from the other side. Gray opened the door, walked in, and sat down in one of the comfortable leather chairs.
"What happened?" Nezu asked, looking up from his paperwork.
"I'm about to open my training dimension," Gray told the principal, laying out his plan. "If you can get in contact with All Might, tell him to send his successor over here right now. Tell him to have the kid tell his mom he'll be going away for a day. Also, let the people on the other end of the tracker know about this thing. I'm going to be away for 24 hours." Gray reached down, touched the ankle monitor, and simply put it directly into his system inventory to get rid of it.
"Got it. I'll let them know and also tell All Might to find you in the training facility. I take it you will be there?" Nezu replied, completely unfazed by the tracking device disappearing into nowhere.
"Yes, that's fine," Gray stood up and walked out.
Nezu quickly dialed a number and told All Might exactly what was happening. On the other side of the line, All Might struggled a little bit with the concept of this magical training dimension. However, if it meant his successor could get stronger faster and get used to the physical toll of his power faster, he was willing to trust Gray for now.
Because of the Senzu Bean Gray had given him earlier, All Might still had a few hours of his muscle form left for the day. He didn't waste any time. He launched himself into the sky and started jumping over to the Midoriya household.
It took him less than five minutes to cross the city. He stopped outside the door, shaking his head as he wondered how to explain this sudden trip to his successor's mother. He finally knocked firmly on the door.
Izuku Midoriya opened the door and came face-to-face with the Symbol of Peace. "All Might?! What happened? I saw the news! Are you okay?!" Midoriya immediately started bombarding his idol with frantic questions.
All Might simply raised his massive hand to stop him. "I'm okay, Midoriya-shonen. In fact, I came to pick you up. Is your mother home?"
"Yeah, she's in the kitchen. Here, come in!" Midoriya opened the door a little wider so All Might could step inside the house.
"Thank you." All Might waited in the living room while Izuku hurried back to get his mother.
Not even a minute later, Inko Midoriya walked into the room. She was incredibly nervous seeing the tall, legendary hero standing inside her house, but she quickly got her bearings together. "What can I do for you, All Might?" she asked, bowing slightly.
"I'm sorry to barge in out of nowhere, ma'am," All Might said, lowering his posture politely. "We have a special school event and we need young Midoriya at the academy immediately. He will not be available for the next 24 hours, so I wanted to personally ask for your permission before we left, since he will not be able to have his phone with him."
Izuku blinked in confusion. "What is this about, All Might? I didn't hear anything about a school event."
"It wasn't planned, but I'll explain it to you on the way," All Might said, giving him a look.
"Is it dangerous?" Inko asked, clutching her hands to her chest.
"No, not at all. In fact, it will be highly beneficial to Midoriya-shonen," All Might reassured her with his signature booming smile. "You could say it will be a small, exclusive training camp to get him fully used to his quirk."
Inko looked at her son, then back at the hero. "I see. That's good then. You have my approval." She gave All Might a deep, respectful bow.
"That's great. Midoriya-shonen, let's go." All Might turned toward the door with Izuku following right behind him. The moment they stepped outside the residential area, All Might scooped Izuku up under his arm and launched into the sky, jumping at high speed toward UA High School.
On the way to the school, Izuku kept asking All Might questions about this special training. "I thought you said I needed to make my body stronger so it's a suited vessel for the quirk," he said, holding on as they flew through the air. "I'm still following the training regime you gave me, so what's this new training camp?"
"You'll see when you get there," All Might replied as he continued jumping toward the campus.
It didn't take ten minutes before they both landed right outside the training facility. Midoriya was amazed by all the massive buildings around him. When he took the entrance exam, he had only seen a tiny part of the school, but seeing the actual campus now left him completely awestruck.
All Might deflated back into his skinny form and started walking toward the entrance. "This way, Midoriya-shonen."
Izuku followed closely behind him. The moment the facility doors hissed open, they came face-to-face with Mirko and Gray sparring. Gray was moving at incredible speeds, while Mirko struggled to even follow his movements with her eyes.
"Stop running around and fight me!" she yelled, getting more and more upset as the seconds ticked by.
Aizawa was standing off to the side, completely silent, just watching one of the top ten heroes in the country get toyed with like a child.
Gray noticed skinny All Might and Deku standing at the door, so he stopped moving. Seeing the opening, Mirko took the chance and tried to drive a heavy kick directly into his side. Gray simply reached out and grabbed her leg without even looking at her, casually tossing her away onto the soft safety mats. Mirko scrambled back to her feet, ready to launch another attack, but she stopped when she realized Gray wasn't even paying attention to her anymore. She just let out an annoyed "tch" and walked over toward the group.
Izuku's eyes widened when he saw Gray standing around inside the building as if absolutely nothing was wrong.
"Wha-wha-what is he doing here?" he stammered, pointing a shaking finger. He had watched the live news broadcast earlier and thought this terrifying villain had been securely caught by the police. So what the hell was he doing inside a UA facility?
"Midoriya-shonen, this is Gray," skinny All Might explained, placing a reassuring hand on the boy's shoulder. "He has offered to help train you and your soon-to-be classmates."
Midoriya stared at Gray in utter disbelief. "But... isn't he a villain?"
Gray burst into a hearty laugh. "Trust me, kid, you don't want me to be a villain. If I were, none of you would stand a chance."
Gray turned his attention toward skinny All Might and Aizawa. "Are you guys going to come along with us?"
Skinny Might gave a nod. "I want to see this dimension for myself and verify if it is truly suitable for training."
Aizawa was also deeply intrigued by the concept of a time-dilated training space. "I'll go," he said, adjusting his capture scarf.
"Perfect," Gray said. He turned around and activated the Training Dimension.
Right before their eyes, a massive, swirling spatial gate tore open in the middle of the gym floor. "Go on," Gray muttered, gesturing for them to step through. He needed them to cross over first, because the moment his own body entered the rift, the gate would automatically snap shut behind him.
Mirko was the first one to step up. Seeing how the men and the teenage boy were hesitating and staring at the portal in fear, she simply scoffed. "Bunch of cowards," she muttered, boldly walking straight into the glowing void without a single shred of fear.
Seeing Mirko vanish into the rift, the others quickly swallowed their anxiety and followed right behind her. Izuku took a deep breath and stepped through, with All Might and Aizawa bringing up the rear. Gray smiled, stepped into the portal last, and the spatial gate instantly vanished from the gym floor.
Up in the main administration building, the high-tech security cameras captured every single second of the bizarre event. Sitting behind his massive desk, Principal Nezu watched the live monitor as the portal securely closed, a deeply satisfied gleam reflecting in his dark eyes.
Once inside the training dimension, everyone stared around at the vast white void. There was absolutely nothing in sight. The moment Gray stepped through, the spatial portal snapped shut behind him.
"Right, this is my training dimension," Gray explained to the group. "I'm in control of everything here, like the terrain." He snapped his fingers, and a massive mountain range violently erupted from the flat ground. "And gravity." With a thought, he dialed the environment up to 2x Earth's gravity.
The pro heroes instantly felt the sudden, crushing weight. Their knees buckled slightly under the heavy pressure, but their trained bodies quickly adapted to the stress. Only Izuku Midoriya looked completely miserable, gasping for air as he struggled to even stand up straight on the grass, seeing that Gray decided to turn off the heavier gravity, making it normal again.
Gray began planning out the perfect curriculum for his guests. For Mirko, he decided to give her advanced Rokushiki training. He willed the system to manifest Black Arm Zephyr, Monkey D. Garp, and Rob Lucci. He took her aside to introduce her to the three legendary powerhouses.
"They will teach you a set of physical martial arts that will come in handy later," Gray told her.
Mirko stared at the three newly manifested figures. Her instincts immediately flared as she sensed the overwhelming strength. She knew deep down that even if she went all out, she wouldn't stand a chance against any of them. "Are these the techniques you used back at the mountains?" she asked, her eyes wide.
Gray nodded. "Yes. I want to see if your body can handle learning them or not."
Next, Gray walked over to Midoriya. He willed the system to manifest Master Roshi's iconic Kame House, along with all the specialized training mountains and delivery routes the old turtle hermit used. A second later, Master Roshi himself materialized on the porch.
Seeing a frail-looking, bald old man holding a wooden cane, Izuku, All Might, and Aizawa looked completely perplexed. Gray noticed their skeptical expressions and smiled.
"It seems you guys don't think he's capable enough," Gray remarked. He turned his eyes toward skinny All Might. "Why don't you go ahead and test him?"
All Might didn't hesitate. He bulked up into his towering muscle form and lunged forward, attempting to throw a swift, controlled punch to test the old man's reflexes. To everyone's shock, Master Roshi effortlessly moved aside, dodging the colossal fist. In a fluid blur, the old master swung his wooden cane right into All Might's gut.
All Might saw the cane coming and tried to grab the wood out of the air. But the physical force behind the swing was far stronger than anything he had ever anticipated. The strike connected, sending the Symbol of Peace flying backward across hundreds of meters until he crashed violently into the newly manifested ocean.
Aizawa and Izuku's jaws dropped, their eyes wide as they stared at the splashing water. A moment later, All Might emerged from the sea, floating in place with a completely bewildered look on his face.
"Just so you know, he's actually one of the weaker teachers available in here," Gray said casually, brushing a piece of lint off his vest.
After witnessing that display of power, All Might and Aizawa completely agreed that this pocket dimension was the ultimate tool for training the next generation of heroes.
Knowing he had a crowd to feed for the next thirty days, Gray walked to an empty zone and placed down several large plots of land from his Home Garden to automatically farm a massive supply of fresh crops and meats. He ordered Aizawa to join Izuku in Master Roshi's grueling physical conditioning course for the time being, planning to move the underground hero over to Mirko's Rokushiki squad once his body grew a bit stronger.
Before the trainees took their first steps, Gray used his clothes beam to manifest custom sets of heavy, weighted training clothes onto Izuku and Aizawa, forcing their muscles to work twice as hard.
With all of his guests placed under their respective masters, Gray walked over to a distant corner of the mountain range to begin his own training. He dialed his personal zone's gravity up to hundreds of times. As his Saiyan cells hummed under the immense kinetic pressure, he began working tirelessly on expanding his stamina reserves.