"Healing Regeneration Technique."
It was the very same large-scale medical jutsu that Shizune and several medical-ninja used to save Hyūga Neji after he was wounded by Kidōmaru of the Sound Four in the original timeline.
In terms of rank, it was at least an A-rank jutsu—after all, anything involving regeneration could never be considered low-level.
However, compared to later techniques like Byakugō no Jutsu, Creation Rebirth, and other regenerative arts that could restore severed limbs or even bring the dead back to life, it seemed rather ordinary.
Tahara Rokuro hadn't expected Orochimaru's first commission for him to be something so middling—a medical-type ninjutsu artifact that sat neither high nor low on the scale.
Just as he was about to ask for details, a thought struck him.
"Wait... Orochimaru shouldn't have mastered Edo Tensei at this point. That means he's still stuck in the phase of live experimentation. And live experiments, inevitably, require medical ninjutsu. Even though Konoha's medical arts are the most advanced among the Five Great Villages—and the number of medical-ninja is also the highest—there's still a shortage of resources."
"Especially during wartime, that shortage becomes even more severe. Even in peacetime, it's unlikely that many medical-ninja would willingly assist Orochimaru in his rather… grisly experiments."
In that instant, Rokuro thought of Yakushi Kabuto.
That man—though ultimately the pinnacle of a civilian-born ninja's rise to power—had been nothing more than a spy before joining Orochimaru.
Yet merely dabbling in medical ninjutsu was enough for Orochimaru to take notice and recruit him.
While that did speak to Orochimaru's sharp eye for talent, even the best seed still needed cultivation. And for someone as obsessively scientific as Orochimaru, having a skilled medical-ninja on hand would certainly be far more efficient than training a rookie from scratch.
From that alone, it was clear Orochimaru didn't have many medical-ninja under his command.
"I see now… He's having me craft a Healing Regeneration-type ninja tool partly as a test—to see how effective my craftsmanship is—and partly to solve his immediate problem. Once the tool is completed, all he'll need is chakra input to activate it. Even a non-medical-ninja could use it. That would drastically boost the efficiency of his experiments."
Having understood Orochimaru's intentions, Rokuro didn't press further. He accepted the ninjutsu scroll for the Healing Regeneration Technique. Though it was also recorded in the Scroll of Seals, it wasn't something he could openly point out.
"An A-rank ninja tool will take about a month to forge," Rokuro said evenly. "I'll need roughly one kilogram of chakra metal, plus another kilogram as my payment. Two kilograms total—though if you're concerned, you can pay half upfront."
"Heh… I have great confidence in your craftsmanship, Rokuro."
Orochimaru handed over the full two kilograms of chakra metal.
Rokuro accepted it, sealing it neatly into a scroll before glancing back at him.
"The commission is fine, but Orochimaru-sama—why are you my jōnin instructor? Didn't the Third Hokage object?"
Orochimaru's smile was faint and serpentine.
"With your strength, Rokuro, there's no need for you to waste time chasing cats or fetching dogs, is there? As for the Third—I've already handled him. You needn't worry. From now on, if you wish to take missions, simply tell me. As for teammates, I can assign subordinates to assist you."
It all sounded fine on the surface—but Rokuro knew full well that in just a few months, Orochimaru would defect from Konoha. When that happened, anyone close to him would be dragged into the fallout.
Still, he didn't have the luxury of time. Following Orochimaru now was indeed the fastest way to gain real combat experience. The pros and cons balanced out, and Rokuro could only accept the arrangement.
Their transaction concluded—payment even received in advance—Rokuro didn't linger. He returned home at once.
And there, another stroke of fortune awaited him.
"One hundred sealing scrolls? The clan head's being unusually generous this time."
No sooner had he arrived than his mother, Uchiha Ashikaga, informed him that Uchiha Fugaku had placed a massive order: one hundred house-sealing scrolls, intended to assist with the clan's relocation.
"One hundred scrolls… at one million each—that's a hundred million ryō! Finally, I can purchase enough chakra metal to craft high-grade tools."
Taking the purchase agreement from his mother's hands, Rokuro even noted the thirty million ryō deposit already transferred by Fugaku. He couldn't hide his satisfaction.
"Rokuro, the clan head hopes to receive them within a month. You think you can manage that?"
"Don't worry, Mom. These are just sealing scrolls—it's far simpler than crafting ninja tools. Just make sure I have enough chakra paper, and I'll handle the rest."
The Rokuro household already stocked plenty of chakra paper for crafting scrolls. Gathering them in his room, he began work immediately.
Creating a sealing scroll was somewhat akin to the Taoist practice of drawing spirit talismans—using chakra as ink to inscribe precise sealing formulas onto chakra-conductive materials.
A skilled seal master could even draw seals on the ground itself—though those on non-chakra materials like dirt, wood, or stone couldn't last long. Just like the one Rokuro had once drawn to absorb the Nine-Tails' chakra—it would fade after a few months even if not activated.
By contrast, a seal drawn on chakra paper could last indefinitely, as long as the paper itself didn't decay.
However, chakra paper could only hold so much energy. Most seals inscribed on it were single-use, or at best reusable three to five times before failing.
Only chakra metal could support repeated, long-term use—making it the ideal material for true ninja tools.
Of course, once a ninja tool was destroyed, its seal would also fail.
Thanks to his past life's coding experience and incredible hand speed, combined with his deep knowledge of fūinjutsu, Rokuro had become an unparalleled sealing master.
And with his ability to draw on the Nine-Tails' chakra, he could, in theory, work endlessly without rest—crafting seal after seal without pause.
On average, he could complete ten scrolls a day with ease.
Indeed, within just five hours, Rokuro had already finished five scrolls. He rubbed his slightly sore eyes and decided to rest for a bit.
As he sank into the sofa, his hand brushed against the scroll Orochimaru had given him.
"Come to think of it, the Healing Regeneration Technique—in scientific terms, that's basically cellular regeneration, isn't it? In the original story, they used one of Neji's hairs to reconstruct his damaged muscle tissue, healing the gaping hole in his chest."
"In modern medicine, that kind of injury—if treated surgically—would leave permanent disability."
"Cell regeneration… cellular fusion… using one's own hair ensures genetic compatibility. But what if you used someone else's genes instead? Wouldn't that be exactly how Kabuto later merged Orochimaru's DNA and the Sound Five's? Once he succeeded, he even mastered the Dragon Cave's Sage Arts—attaining near-perfect Sage Physique!"