"Get him on the central table! Now!"
The medical tent erupted into chaos as the stretcher bearers slammed the cot down. Nawaki Senju lay motionless, his chest a ruin of burnt flesh and shrapnel.
A senior medical ninja—a member of the Senju clan himself—rushed forward. His hands glowed green as he pressed them desperately against Nawaki's chest. He poured his chakra into the boy, trying to jumpstart the system, but his expression quickly crumbled from determination to horror.
"It's no use," the senior medic stammered, his hands shaking. "The damage to the aorta is too severe. His heart... it's barely fluttering. It's stopped." He stepped back, defeat washing over him. "He's gone."
"Move."
Ren shoved past the frozen medic. He didn't waste time arguing. He placed his hands over the mangled chest and activated his technique. The emerald green aura, heavily saturated with Natural Energy, flooded into Nawaki's body.
What Ren felt next shocked him.
Usually, he had to guide the healing energy carefully. But Nawaki's cells reacted instantly. They were ravenous. Upon contact with the Natural Energy, the Senju cells began to vibrate, aggressively absorbing the power and attempting to knit themselves back together.
'This resilience…' Ren thought, his Sharingan analyzing the cellular activity. 'His body isn't dead. It's fighting with everything it has. The Senju vitality is trying to heal the heart, but it can't.'
The problem wasn't a lack of life force; it was the obstruction.
"Bone shards, metal fragments, and stone debris," Ren muttered, his eyes scanning the internal structure. "They are lodged in his lungs, liver, and deeply embedded in the heart muscle. The tissue can't close because the debris is blocking the regeneration."
He had seconds. The brain would die without oxygen.
Ren formed a cross seal.
"Shadow Clone Jutsu!"
Poof! Poof! Poof!
Three identical Rens appeared around the operating table, crowding out the stunned senior medic. They moved with a synchronized, terrifying efficiency.
Clone 1 placed its hands on Nawaki's forehead and solar plexus. "Stabilizing. I'm feeding a constant stream of Natural Energy to keep the brain and cells oxygenated."
Clone 2 grabbed the surgical tweezers and retractors. "I'm going for the lungs and liver. Extracting shrapnel now."
The Main Body focused entirely on the heart.
Ren's hands moved at a blur. He wasn't just using chakra; he was physically reaching into the open cavity. With surgical precision enhanced by his mental acuity, he began extracting jagged pieces of rib bone that had pierced the heart.
"What are you doing?!" the senior Senju medic shouted, finding his voice. "Stop! His heart has already stopped! You're desecrating a corpse! You can't save him!"
Ren didn't even blink. He ignored the man completely.
'Fragment removed. Arterial wall exposed. Next.'
Blood welled up, but the constant flow of Natural Energy from Clone 1 kept the cells from dying, while Clone 2 tossed bloody pieces of metal into a metal tray—clink, clink, clink.
Finally, the Main Body pulled a jagged, three-inch piece of shrapnel from the left ventricle.
"Debris cleared," Ren announced.
Immediately, all three Rens shifted their focus. They poured the 1:10 ratio of Chakra and Natural Energy directly into the organs. The tissue responded violently. Under the boost of Nature Energy, the holes in the lungs sealed, the liver regenerated, and the heart muscle knitted itself back together.
But the chest remained still. The heart was whole, but silent.
"It's healed," the senior medic whispered, staring. "But… it's not beating. The trauma was too great."
Ren stepped back, his expression focused. "Clear."
"What?"
Sparks of blue electricity suddenly crackled around Ren's right hand. The medics in the tent gasped, confused and terrified. Lightning Release was a destructive nature; using it in a hospital tent seemed like madness.
"Ren, what are you—"
Ren ignored them and pressed his hand against Nawaki's chest.
ZZAAP!
Nawaki's body jolted on the table.
Silence. The heart didn't move.
"Frequency too high," Ren muttered. He adjusted his chakra control, altering the voltage and amperage of the lightning to mimic the body's bio-electric signals.
ZZAAP!
Nothing.
ZZAAP!
Still nothing. The senior medic looked down, shaking his head.
Ren narrowed his eyes. "Come on." He gathered a precise burst of lightning chakra, targeting the sinus node of the heart.
ZZAAP!
…Thump.
The room went deathly quiet.
Thump-thump. Thump-thump.
A strong, steady rhythm filled the silence, visible against the boy's healed chest.
Ren immediately flooded the area with one last massive wave of healing chakra. The skin over the chest zipped closed, leaving behind only a faint, pink scar. Nawaki took a deep, sudden gasp of air, his chest rising and falling on its own.
"Stable," Ren said, exhaling a long breath.
He dispelled his three clones. The room spun slightly—the fatigue was catching up to him—but he held his ground.
The medical ninjas were frozen. They looked from the breathing boy to Ren, their eyes wide. They weren't looking at him like a Genin anymore. They were looking at him as if he were a god who commanded life and death.
Ren wiped his hands on a towel, looking slightly exhausted. He turned to the senior Senju medic, whose jaw was practically on the floor.
"He's fine," Ren said calmly. "He'll wake up in a few hours. But his body used a lot of reserves to accept that healing. Make sure he stays on bed rest for at least two to three months. No training."
Without waiting for a response, Ren turned and walked out of the critical care unit. As he passed through the main ward, he saw his twenty other Shadow Clones still moving tirelessly from patient to patient, handling the overflow of injured.
Ren walked toward his mother's tent, intending to collapse.
Moments later, the entrance to the medical camp burst open.
Sakumo Hatake rushed in, with Tsunade close on his heels. She looked frantic, her eyes red, fearing the absolute worst.
"Where is he?!" Tsunade screamed.
The senior medic, still standing over Nawaki, pointed down. "He's… he's sleeping, Lady Tsunade."
Tsunade rushed to the table. She saw the breathing. She checked the pulse. It was strong. She ripped open his shirt and saw the fresh scar tissue where a fatal wound should have been.
She fell to her knees, clutching her brother's hand, sobbing in relief. She looked up at the senior medic. "You… you saved him? His injuries… based on the report, he should be dead."
The senior medic shook his head slowly, looking toward the tent exit where a young boy had just left.
"I didn't do anything," the medic admitted, his voice filled with reverence. "His heart had stopped. It was Ren Uchiha. He… he brought him back from the dead."