When Nurse woke up groggily, the surgery was already done.
Her body was still numb, her tongue fumbling in her mouth, unable to form a single coherent word. Her right hand had been reattached, the wound wrapped in gauze with a delicate butterfly knot tied on top, but she still couldn't feel a thing.
"Nerve reconnection is delicate work. Honestly, your talent is… unmatched," said Chihaya Toru, who had taken on the role of assistant, wiping down the blood-stained surgical tools while praising Hikari beside him.
It was one thing to have incredible combat talent, but who would've thought she'd pick up medical ninjutsu so quickly?
He'd explained the procedure once, demonstrated it once, and after a few practice runs, Hikari could replicate every movement perfectly. Her small hand wielded the scalpel with more precision than his blood pressure, slicing cleanly without a hint of hesitation or psychological burden.
As for her chakra control? That didn't even need mentioning.
During her training, Chihaya had noticed that her frequent mistakes stemmed from her chakra's overwhelming ability to channel vitality, making precision tricky. But solving that was just a matter of time. After several attempts, she'd finally nailed the sweet spot.
Physiological knowledge? He guided her through that. Once her body and chakra control caught up, even the most complex medical ninjutsu became almost trivial.
Grinning ear to ear as he wiped blood from the edge of the operating table, Chihaya was in high spirits. With Hikari's help, experiments and medical work would be so much easier. He was sick of dealing with the idiots outside every day.
"How're you feeling?" Hikari asked with concern, noticing Nurse was awake.
Though her Byakugan had already confirmed the successful reconnection of neurons and the resulting electrical signals, she still lacked confidence about her first-ever surgery.
"Nn… nn…" Nurse's tongue was still tied, but she responded by gently curling the fingers of her newly reattached hand.
Seeing the gesture, Hikari broke into a warm smile. The nerves were connected, and the rest was just minor details. Her first surgery was a complete success.
You really could learn some serious skills at Root!
Ding ding!
Chihaya turned off the "Surgery in Progress" light at the door. Moments later, a flurry of hurried footsteps echoed as several nurses pushed a cart into the operating room.
"Alright, we're done here. Let's go—I'll show you where you'll be working from now on," Chihaya said.
"Will I be working in the lab all the time?" Hikari asked.
"When there's no mission, yeah. By the way… can I take a vial of your blood?" Chihaya asked, looking at Hikari with eager anticipation.
Whoosh!
Invisible threads of wind stirred faintly around Hikari's body.
"Okay, okay! Just kidding!" Chihaya's eyelids twitched as he sensed danger, immediately throwing up his hands in a mock surrender, striking a dramatic pose.
Ignoring his theatrics, Hikari's expression remained icy. "If there's a next time, I'll tear you apart."
Sensing the seriousness in her tone, Chihaya slowly lowered his hands, his exaggerated expression fading into cold calm. "Kill me, and you'll die horribly."
"Oh, I'm curious to see that," Hikari replied, her gray pupils glinting with killing intent. As a mere shadow clone, she wasn't fazed by his threat.
The two locked eyes across the room. The air in the operating room grew heavy with tension.
"Pfft! You're just like Orochimaru!" Chihaya said, realizing he couldn't intimidate her. He smacked his lips in disappointment, dropping the cold act and strolling out of the operating room with a bored expression, as if his earlier enthusiasm had been an illusion. He didn't even check if Hikari was following.
"Who's Orochimaru? One of your test subjects?" Hikari probed, trailing behind.
"If only," Chihaya muttered, rolling his eyes. His patience for Hikari plummeted since she wasn't up for being studied. The golden spark of goodwill in his demeanor dimmed significantly, and even the malice faded a bit.
They passed through the honeycomb-like structure and soon arrived at a pitch-black basement. The walls and doors were covered in intricate sealing techniques and curse marks. When Hikari activated her Byakugan, the chakra fluctuations were almost blinding.
This was clearly the heart of the lab.
"The lab's split into two parts," Chihaya explained. "The honeycomb upstairs is for monitoring test subjects or treating injured Root ninjas. Down here is where we store the key materials for human experiments. That chunk of life-filled flesh you saw the other day? That's a product of this place."
He glanced at Hikari to gauge her reaction.
Bringing Hikari into the lab was Danzo's idea, and the plan was eerily similar to Orochimaru's back in the day. Orochimaru had gone from a ninja obsessed with mastering ninjutsu to being lured by Hashirama cells into joining Root. He'd worked with Chihaya on dark, bloody human experiments, eventually becoming consumed by them and falling out with Sarutobi Hiruzen. The whole thing was orchestrated by Danzo.
Aside from the Otherworldly God technique and being one of Danzo's disciples, Hikari's entry into Root was practically a carbon copy of Orochimaru's. Even the person who accompanied Orochimaru during his Root registration was Aburame Ryoma.
Talk about bad taste.
Chihaya quickly formed hand signs, his five fingers glowing as he pressed them against the barrier on the basement door.
Buzz!
The barrier flashed red. As Chihaya infused his chakra, a peculiar pattern formed on its surface: two wavy lines with a massive hole in the center made of countless arcs, and within it, a curled symbol resembling an infinity sign (∞).
Was this a chakra signature?
Seeing the pattern on the barrier, Hikari instantly thought of her own chakra signature. Then she recalled the moment Butterfly opened the sealed base's entrance. Butterfly had infused chakra into the barrier, forming a maze-like pattern of jagged lines. At the time, Hikari thought it was just part of the barrier's design, but now it clicked—that was Butterfly's chakra signature.
Buzz!
The barrier flashed red again. The moment the chakra signature formed, it was like a password being entered. The barrier dimmed, revealing its mechanism. The curse seals etched on the disk were incomplete versions extracted from this sealing barrier. Infusing chakra into the barrier automatically generated a signature, and only if it matched the stored pattern would the passage open.
"Normally, you wouldn't be allowed in here," Chihaya said, pushing open the basement door. He glanced at Hikari, who was already stunned the moment the door opened, and smirked. "You're my lab assistant, so you'll be helping with experiments. I need to explain the research, and it's easier to show you here. You may or may not see it, but this is Root's greatest treasure—no question about it."
Gulp!
Hikari swallowed hard, her eyes blankly fixed on the massive glass pillar in the center of the basement. Despite mentally preparing herself, the sheer scale of the thing still shocked her.
Seeing her dumbfounded expression, Chihaya gave a knowing smile. Few people could stay calm when they saw this.
"Come on," he said, nudging her forward.
As they approached, the glass pillar loomed even larger, and the object inside came into full view.
Hikari craned her neck, unsure how to process what she was seeing.
It was a colossal tree.
Its lush, green canopy stretched out like a sea, and the deep brown trunk was covered in countless grotesque human faces, mouths open in a pleading expression.
Even more horrifying was the tree's base: a pale, fleshy mountain pulsed slowly in the giant incubation chamber. Hundreds of human bodies were fused together like melted wax, forming the foundation. Limbs not fully assimilated jutted awkwardly from the tumorous surface, their exposed muscle fibers a waxy gray, coated in a slimy, moss-like biofilm that constantly secreted mucus.
Gurgle, gurgle!
The flesh writhed slowly.
The vibrant green sea of life felt hotter to Hikari than molten lava.
This was too much.
"Pretty incredible, right? That chunk of flesh you saw the other day? It's part of this," Chihaya said.
Clack, clack!
His teeth chattered uncontrollably as his voice trembled with excitement, his body shaking as if electrified. No matter how many times he saw it, this massive organism never failed to awe him.
"Can you feel that incredible vitality?" he asked. "With this kind of power, human lifespan, disease, disability—everything—can be…" He was so overwhelmed he could barely speak, his hands repeatedly stroking the transparent glass, his eyes filled with an indescribable longing.
"Calm down, Dr. Chihaya," Hikari said.
"Oh, uh, sorry," he replied, forcing himself to suppress his excitement. He closed his eyes, took deep breaths, and slowly regained his composure.
"So, what's our research goal?" Hikari asked, staring at the chaotic ocean of chakra. For some reason, she felt a bit disinterested.
"These are cells extracted from the First Hokage's body," Chihaya said, his face tinged with frustration. "The goal is to safely and stably transplant Hashirama cells into a human body to gain the First Hokage's power."
Using a miracle cure that could solve humanity's ultimate problems for something as fleeting as power? That was the directive from Root's leader.
Boring and ignorant.
"After several tragic failures, we've only had two successes," Chihaya said, pointing at the fleshy mountain. "One is this source that can produce Hashirama cells almost infinitely. The other is a failure with a corrupted chakra core that inherited the First's Wood Release kekkei genkai."
"Isn't that a success?" Hikari's heart skipped a beat.
Transplanting Hashirama cells to gain a Sage Body was her main reason for joining Root. And didn't Danzo destroy the Uchiha to use the Sharingan to suppress the cells' corruption? How could it not have worked?
"What made Hashirama Senju so powerful wasn't his Wood Release," Chihaya said dismissively. "It was his near-infinite vitality and chakra core. What's the point of just inheriting Wood Release?"
"Infinite chakra core?" Hikari scratched her head, realizing her knowledge had some gaps.
Noticing this, Chihaya sighed deeply and decided to give her a crash course on chakra trivia.
"First, you need to understand what a chakra core is. That thing in your heart, absorbing physical and mental energy to produce chakra? That's your chakra core."
Hikari placed a hand over her heart.
Thump, thump, thump.
A purple energy core pulsed with light. Physical energy from her cells gathered in her dantian, colliding with mental energy from her brain at the core.
"Body, soul, energy—the chakra core fuses these three and creates a power that can shape anything," Chihaya explained.
Thump, thump!
The core beat in sync with her heart, absorbing energy from her meridians and producing purple chakra with infinite potential.
"Everyone's soul and body are different, so their chakra core and the chakra it produces are unique. That's why chakra signatures can identify someone," he continued.
Hikari nodded. Aside from chakra signatures, this was basic stuff taught at the Ninja Academy, and she knew it well.
Seeing her solid foundation, Chihaya smiled approvingly and went on. "All of a ninja's power and information is stored in their chakra core, including legendary kekkei genkai. In theory, if you could replicate a chakra core, you could create an exact copy of that person."
"Shadow clones?" Hikari mused, thinking of her Yang Release clone.
"Exactly. Shadow clones work by using chakra's mimicry to create a fake chakra core that contains all the original's information. That's why they can use the same powers as the original. They don't have a body or soul—just chakra simulating the original's actions and thoughts," Chihaya explained, summing up the essence of shadow clones in a few sentences.
"So what's this got to do with Hashirama cells?" Hikari interjected, not wanting him to ramble.
"Hold on," Chihaya said, waving her off, oblivious to her impatience. "Normally, a chakra core goes through six cycles: seed, sprout, growth, flowering, aging, and withering. Once it withers, it can't produce power anymore. But the First Hokage's was different. For some reason, his cells can endlessly absorb physical and mental energy to grow. When they reach a certain point, they can automatically form a chakra core and produce chakra."
He turned, gazing at the massive tree trunk with obsessive fascination, on the verge of losing himself again.
Ahem!
Hikari coughed lightly, interrupting his trance.
"Oh, sorry!" Chihaya snapped out of it, slapping his forehead. "Here's the thing: human vitality and chakra cores have limits. Based on a person's lifespan and their core's growth cycle, you can calculate exactly how much chakra they'll produce in their lifetime. Hashirama cells break that limit. As long as there's biological energy to consume, they can keep producing vitality. Even when a chakra core withers, they can form a new one. It's just—"
"Get to the point. Why'd it fail?" Hikari cut in bluntly.
"We found that Hashirama cells aren't normal. They're a diseased cell structure," Chihaya said, his face full of regret.
"Konoha's history books don't say how Hashirama Senju died. Some speculate he died from unhealed injuries, but—look at this. Even decades after his death, his cells are still vibrant and full of life. Who'd believe he died from injuries? After years of experiments, we found that Hashirama didn't die from wounds or old age. He died from a disease!"
"What disease?" Hikari's brows furrowed, sensing he was getting to the crux.
Looking at the thriving tree in the glass pillar, Chihaya held up a finger. "A disease only a genius ninja could get—one ordinary people couldn't even dream of: a kekkei genkai disease!"
Support me by leaving a comment, voting, and visiting myPatr-eon at belamy20