Fifteen minutes passed. It felt like fifteen hours.
The dirt floor of the arena was soaked in sweat. The sound of heavy, ragged breathing echoed off the cold steel walls.
Jin pulled his torso up from the dirt. His stomach muscles cramped violently. It was a sharp, blinding pain. It felt like a hot knife twisting directly under his ribs. He gritted his teeth. He lowered his back to the ground. He pulled himself up again.
Down. Up. Down. Up.
He was moving purely on willpower. His Foundation Level 4 core was completely empty. There was no Aether left to support his movements. It was just raw, mortal muscle tearing itself apart.
All around him, the class was breaking.
Many students simply stopped moving. They lay flat on their backs in the packed dirt. Their eyes stared blankly at the dark stone ceiling. Their chests barely moved. They looked completely hollow. It was as if their souls had finally given up and left their broken bodies behind to escape the terrible physical pain.
Rich children in expensive silk uniforms lay next to poor scavengers in cheap cloth. Exhaustion made them exactly equal. None of them could lift their arms. None of them could bend their knees.
The tall instructor stood in the center of the arena. His massive arms were crossed. His eyes were closed. He looked like a stone statue.
Then, he opened his eyes.
"Okay," the instructor said. His deep voice cut through the sound of panting students. "Everyone stop."
The students froze.
Nobody sighed in relief. Nobody cheered. The mood in the dirt arena instantly turned incredibly tense.
The students stopped their sit-ups and squats, but they did not relax. They stayed completely still on the ground. They stared at the giant man in the center.
Their minds were pushed to the absolute brink. Physical torture makes a human brain irrational. They were expecting him to announce the next phase of the punishment. They expected him to tell them to start crawling, or to start carrying heavy stones.
A dark, desperate anger started to boil in the crowd.
They were teenagers. They were exhausted, hurting, and humiliated. A silent agreement passed through the hundreds of students lying in the dirt. If this giant man told them to run one more lap, they were going to rush him.
It was a completely insane thought. He was a high-level expert. He could probably kill all of them with a single shockwave from his lungs. They could not even stand up properly. But the pain made them crazy. They were ready to gang up on him just to make the torture stop.
The instructor looked around. He felt the heavy, irrational anger radiating from the dirt floor. He saw their bloodshot eyes and clenched fists.
He did not smile. He did not look threatened.
Different to their expectations, the instructor simply opened his mouth and gave a very calm command.
"Sit down, everyone," he said. "Cross your legs."
The tension snapped instantly.
The irrational anger vanished, replaced by complete physical collapse. The students did not argue. They dragged themselves up from the dirt. They sat cross-legged on the ground. Their shoulders slumped. Their heads hung low. They looked like a defeated army.
Jin pushed himself into a sitting position. His abdominal muscles screamed in protest, but he forced his back straight. Luna sat next to him. She looked completely pale. She was shaking slightly from the adrenaline leaving her system.
The tall instructor started to slowly pace in a small circle in the center of the room. His heavy boots made soft thuds against the dry dirt.
"My name is Instructor Thorne," the giant man said. He pointed a thick finger at the massive racks of steel weapons lining the walls. "You all walked in here today looking at the swords. You looked at the heavy spears and the battleaxes. You wanted to grab a weapon. You wanted to swing it around and feel strong."
He stopped pacing. He looked directly at a rich boy in the front row who was holding his cramping legs.
"You are not strong," Thorne stated bluntly. "You are weak. Your bodies are fragile."
Thorne picked up a simple, heavy iron broadsword from a rack near him. He held it in one hand.
"A sword swing does not come from the arm," Thorne explained. He demonstrated a slow, perfect downward strike. "The power comes from the ground. It travels up through your legs, twists through your hips, tightens in your core, and finally releases through your arms."
He tossed the heavy iron sword back onto the rack. It landed with a loud metallic clang.
"If your legs are jelly," Thorne said, "you have no foundation. If your core is weak, your swing has no power. If I let you pick up a heavy steel weapon right now, you would tear your own shoulder muscles just trying to lift it. You would break your own wrists trying to block a real strike."
He started pacing again. He laid out the absolute rules of his arena.
"I will not allow anyone to touch the steel," Thorne declared. His voice was strict and unyielding. "You do not earn a weapon until you earn your baseline physical strength."
He raised his thick hand and started counting off his fingers.
"You will run at least fifty laps without stopping," Thorne said. "You will do one hundred sit-ups. One hundred squats. One hundred push-ups. One hundred pull-ups. That is the baseline. Until you can finish that routine without vomiting in my dirt, you do not touch a single blade in this room."
The students groaned quietly. The numbers sounded impossible. They had barely survived a fraction of that today.
"Stop feeling sorry for yourselves," Thorne snapped. "You are cultivators, not common farmers. Your bodies are built to adapt. The physical tearing is just the first step. Now, we rebuild."
He stopped in the center of the room again. He faced the exhausted crowd.
"Start using your breathing techniques," Thorne ordered.
He raised his hand to stop the immediate wave of confusion from the poorer students.
"Those of you from wealthy families, use your inherited legacy breathing techniques," Thorne instructed. "For the rest of you who do not have a legacy yet, or those who have not met the starting requirements for your chosen gene, do not panic. You will use the universal basic breathing technique."
Thorne stood perfectly straight. He demonstrated the rhythm.
"It is simple," Thorne explained. "Breathe in deeply through your nose for three seconds. Pull the air down into the bottom of your stomach. Hold it there for one second. Exhale slowly through your mouth for three seconds. Focus your mind on the pain in your muscles while you do it."
It was a standard, safe rhythm. It was not aggressive. It was designed to slowly pull ambient Aether into the body without causing any strain on the blood vessels.
"Do it now," Thorne commanded.
The students closed their eyes. The arena grew quiet again. The only sound was the collective, rhythmic breathing of hundreds of teenagers.
Jin closed his dark eyes. He sat perfectly still.
He did not use the universal basic technique. He did not need a safe, slow rhythm. He had his manual. He had the Devourer legacy.
Jin started the aggressive, violent breathing pattern he had practiced last night. He pulled the air in sharply. He forced his lungs to expand completely. He held the heavy Aether inside his chest tightly, then hissed the air out through his teeth.
The reaction in his body was immediate.
During his run and his sit-ups, he had completely emptied his Foundation Level 4 core. He had starved his cells of fuel. He had created thousands of tiny, microscopic tears in his thigh and stomach muscles.
Now, his empty body acted like a dry sponge dropped into a bucket of water.
The dense ambient Aether of the Genesis Zenith Academy rushed into his lungs. The aggressive Devourer breathing pushed that raw energy directly into his bloodstream.
The Aether flooded his torn muscles.
The pain in his legs and stomach instantly changed. It stopped being a sharp, stabbing ache. It turned into a deep, intense heat. It felt like hot water was pouring over his torn muscle fibers.
The raw energy acted like a biological glue. It filled the microscopic tears in his flesh. It knit the broken fibers back together. As the Aether sealed the damage, the muscles became slightly denser. They became heavier. They became stronger.
Jin focused entirely on the heat. He kept his breathing steady. The healing process was rapid. The exhaustion was slowly being pushed out of his limbs, replaced by a fresh, solid weight.
Next to him, Luna also sat with her eyes closed.
She could not use the specific breathing technique from her silver book. The space legacy required her to assimilate a space beast core first. She did not have the catalyst. If she tried the space breathing now, she would just pull empty air.
So, she used the universal basic technique Thorne had just taught them.
She breathed in for three seconds. She held it. She breathed out for three seconds.
It was a slow process for her. She was a mortal. She did not even have a Foundation Level 1 core to act as a magnet for the energy. But her body was completely exhausted, and it was desperate for relief.
Slowly, tiny particles of ambient Aether drifted into her lungs. The energy was weak, but it was enough to start soothing her burning legs. The extreme pale color of her face slowly faded. A faint, healthy pink returned to her cheeks. She was healing.
The dirt arena was completely silent. Instructor Thorne stood watch over them.
The lesson was perfectly clear to Jin. Practical combat was not about swinging swords or learning fancy martial arts moves. It was a brutal cycle. You empty the body through extreme physical torture. You break the muscles. Then, you sit in the dirt and force the Aether to rebuild you stronger than before.
It was highly efficient. It was exactly the kind of process Jin respected. He kept his eyes closed and pulled another heavy breath of Aether into his starving lungs.