As distant relatives of the Senju clan—the descendants of Asura—the Uzumaki clan were not to be underestimated, even during the turbulent Warring States Period.
Though not particularly skilled in direct combat, and certainly lacking the martial might of the Senju or the Uchiha, the Uzumaki still held immense influence across the shinobi world.
Their strength lay in their mastery of sealing techniques—an art that demanded both innate talent and systematic education.
And in the chaotic world of warring shinobi, proper education was a luxury few could afford.
After Ashina Uzumaki's rise to power and the founding of the Land of Whirlpools' village, Uzushiogakure, he took deliberate measures to prevent his clan from directly participating in shinobi conflicts.
Of course, complete isolation was impossible. As one of the spiritual successors of Ninshū, and allies of the Senju, some level of involvement was inevitable.
Nonetheless, by taking advantage of the Land of Whirlpools' unique geography, Ashina Uzumaki maintained the clan's independence while quietly developing under the Senju's protection.
With their relatively small population yet vast resources, they prospered in silence—an example of true strategic restraint.
"It's for that reason," Ranzuki mused, "that the Uzumaki's decision to voluntarily disclose information regarding their 'Jinchūriki' research to us carries significant meaning."
Since accepting Satsuki's directive, Ranzuki had been contemplating how best to deepen their engagement with the Uzumaki clan.
Her initial thought had been the Hyūga, but the Byakugan's status as a kekkei genkai made it far too conspicuous. Moreover, the Hyūga were only temporarily stationed in Uzumaki territory—they would soon return to the Senju domain. For these two reasons, they were unsuitable intermediaries.
"Who, then, should we send…?"
The question lingered in Ranzuki's mind until, two days later, she received word that Shirakumaru had just returned from the Uchiha clan's compound and was currently reporting his mission's completion in the assignment hall.
Her eyes lit up.
"If Shirakumaru-senpai were to serve as our intermediary with the Uzumaki, he would be perfect for the role."
As long as he avoided revealing his Sharingan in public, there would be no problem.
Moreover, as a former daimyō's bodyguard, he possessed some understanding of sealing techniques. During research discussions, he would not be easily manipulated or exploited.
Thus, Ranzuki promptly contacted him through a telepathic transmission.
Not long after, Shirakumaru arrived at the Lunar Capital.
At that moment, Satsuki's clone still sat upon the high throne, though she spent most of her time in silence—usually hidden, observing events without directly appearing before outsiders.
To most, the highest seat of authority appeared perpetually vacant.
And by now, few within the shinobi world even knew who had once occupied it.
But Shirakumaru was among the few who did.
Years had passed, and the Lunar Capital had changed drastically since his departure.
Yet Shirakumaru, ever stoic and soft-spoken, showed no surprise. Upon entering the grand hall, he first bowed respectfully toward the positions of Satsuki and Ranzuki before straightening and speaking in his usual calm tone.
"Lord Ranzuki, may I ask what mission you've summoned me for?"
Within the Lunar Capital, Shirakumaru was regarded as a particularly unique existence.
Though not a Tenseigan-reincarnated puppet, he nonetheless possessed a degree of self-awareness and independent thought. Moreover, he had joined Satsuki's ranks at a very early stage.
At the time, his strength had placed him among Satsuki's top generals.
With seniority, power, and a flawless record of completed missions, Shirakumaru had earned a position of considerable respect.
Although Ranzuki was Satsuki's first Tenseigan-reborn puppet, she remained courteous toward these veteran subordinates.
"There's no need for such formality, Shirakumaru-senpai. Lady Satsuki has already relayed her next directive to me through the Giant Tenseigan. Lord Kiyomaru is currently preparing the cell fusion materials required for your enhancement. Knowing his efficiency, it should be ready any moment now."
"I am most grateful."
Shirakumaru's response was as direct and unembellished as ever. Even after his rebirth, he had never been one for flowery words—always straightforward and to the point.
The relationship among these few individuals was highly unusual—they shared nearly absolute trust in one another. Thus, there was no need for any formalities or empty pleasantries.
After briefly exchanging updates on recent matters, a puppet soon reported from outside, "Lord Kiyomaru has arrived from Rōran with a squad of puppets."
"It's quite lively out there."
When Kiyomaru entered the Lunar Capital, he immediately noticed the piles of shattered stone fragments from the disassembled puppet army and the massive statue of Hamura towering nearby.
Even after all these years, his gravelly, booming voice remained as loud as ever.
Upon seeing Shirakumaru, Kiyomaru took a scroll from one of the puppets behind him and handed it over.
"Shirakumaru, this is what Lady Satsuki instructed me to deliver to you. Make good use of it—don't waste it. Otherwise, I'll report it straight to Lady Ranzuki."
Shirakumaru replied in his usual blunt manner, "Understood."
"Tch—"
Ranzuki couldn't help but let a few dark lines appear across her face at that response.
But she quickly turned the conversation to business.
"This concerns the Uzumaki clan's 'Jinchūriki' technology. I'd like to entrust this mission to you, Shirakumaru-senpai."
"The Uzumaki clan, I've heard of them," Shirakumaru said thoughtfully. "They may not be strong in battle, but their sealing arts are exceptional… Still, what exactly is this 'Jinchūriki'?"
"It's a technique that allows a human to harness the power of a tailed beast."
To use the power of a tailed beast through the human body?
Having personally witnessed the Nine-Tails wreak havoc upon the Uchiha compound, Shirakumaru found the notion difficult to believe.
After all, by any reasonable measure, the gap between a human and a tailed beast was insurmountable.
To contain such a being within the human body seemed like pure fantasy.
However—
"Since Lady Satsuki herself has deemed it important, it must hold great significance. I am willing to undertake this mission to the Uzumaki clan. Should I attempt to acquire this technology by covert means?"
If the order came from Lady Satsuki, there could be no doubt about its authenticity.
Ranzuki blinked, waving her hands quickly. "No, no, nothing like that. The Uzumaki clan's work on this technique is still in its confidential research phase. Lady Satsuki values this technology greatly, so I've already proposed a formal collaboration with them. You will be sent as one of our representatives in this joint effort."
"Research work?" Shirakumaru frowned slightly. "But I lack any experience in such matters."
"There's no need for prior experience."
Ranzuki explained honestly, "According to Lady Satsuki's analysis, the Jinchūriki technique is fundamentally based on sealing arts. As long as you use your Sharingan to learn and record their clan's sealing techniques, there shouldn't be any issue."
"I understand."
In the end, Shirakumaru departed carrying a handwritten letter of recommendation personally signed by Ranzuki.
At the same time, Ranzuki contacted the Hyūga clan members stationed in Uzushiogakure through the Giant Tenseigan, instructing them to inform the Uzumaki clan in advance of Shirakumaru's impending arrival.
Thus, the mission's beginning could be considered a promising one.
At that moment, Satsuki's work with Tenjin Hyūga on modifying natural energy had already been underway for two full days.
Throughout the process, she used her [Energy Control] authority to repeatedly adjust and refine the flow of natural energy—countless times over.
After each adjustment, the modified natural energy was allowed to merge with the spiritual and physical energies within Tenjin Hyūga's body, forming trace amounts of Sage Chakra. Satsuki then extracted it and observed its effects on his chakra network.
Given her current efficiency, she was able to perform hundreds, even thousands, of such energy configurations simultaneously.
And finally, her efforts bore fruit.
In Satsuki's palm, there now floated a small sphere of natural energy—half black, half white—spinning on its own like a tiny vortex.
"It seems that the Yin-Yang Release techniques left behind by Ancestor Hamura also apply perfectly to natural energy."
To Satsuki, Yin-Yang Release was no longer a mysterious concept. As the sovereign of the Ōtsutsuki lunar branch, such knowledge had long been considered elementary material—akin to grade-school lessons.
The defining trait of Yin-Yang Release was its ability to create life from nothingness—it was, quite literally, the art of creation.
Yin Release represented spiritual power, and through Yin Release Techniques, one could give form to the formless.
Yang Release represented physical vitality, and through Yang Release Techniques, one could breathe life into form.
Together, they became Yin-Yang Release—the power to shape existence itself.
After receiving the Sage of Six Paths' power, Naruto had demonstrated this mastery—using Yin-Yang Release to save Might Guy's life and even create a new eye for Kakashi.
From that alone, it was clear that Yin-Yang Release was a power capable of rewriting fate—a technique comparable, in effect, to the Root of the Type-Moon world.
According to the records preserved in the Throne of Heroes, the Root could create heroic spirits from nothing, grant them life and power, and send them into battle.
Was this not strikingly similar to the Sage of Six Paths' Creation of All Things Technique? Even in myth, he had divided the power of the Ten-Tails to create the nine tailed beasts.
The resemblance was uncanny.
"And fittingly, the Tenseigan's dual powers of destruction and creation embody the purest form of Yin-Yang Release."
That was why, upon awakening her Tenseigan, Satsuki had immediately ascended to the legendary Six Paths level and manifested Truth-Seeking Orbs.
However, despite Yin-Yang Release's ability to nullify all forms of ninjutsu, there still existed one thing it could not overcome—Sage Arts.
Yet, the relationship between the two was not as absolute as commonly believed.
Through her research, Satsuki discovered that the reason Sage Arts could counter Yin-Yang Release was, in essence, quite simple: Yin-Yang Release, though vastly superior to ordinary chakra-based techniques, still belonged to the chakra system. Its limitations stemmed from the authority hierarchy established by the Ōtsutsuki.
It was not that Yin-Yang Release was inherently weak—it was simply bound by the rules set by its creators.
Just as modern jonin understood that the five elemental chakra natures—fire, water, wind, earth, and lightning—possessed mutual strengths and weaknesses, forming the basis of a complete combat system, Yin and Yang chakra existed on a much higher plane of that same structure.
"In the original story, many shinobi possessed Yin or Yang chakra attributes. Some, like Hatake Kakashi, even had both."
"However," she continued, "shinobi like Nara Shikamaru, who used Yin-based chakra, and Akimichi Chōji, who used Yang-based chakra, merely employed their chakra to perform clan secret arts—like the Shadow Imitation Jutsu or Multi-Size Technique."
Even Kakashi, who wielded seven chakra natures, had never once used Yin-Yang Release or manifested Truth-Seeking Orbs.
Ultimately, possessing Yin or Yang chakra alone was meaningless without the proper heritage.
And that heritage—everyone knew—came down to whether one possessed the bloodline of the Ōtsutsuki.
In contrast, the greatest strength of Sage Arts lay in the fact that they had no such hereditary restrictions.
As long as one could refine Sage Chakra, they could perform Sage Arts.
Different Sage Lands naturally produced Sage Chakra with unique properties. Likewise, Sage Techniques learned from the same land always shared common characteristics.
This inherent consistency was what gave Sage Arts the potential for inheritance and evolution.
Since Yin-Yang Release was itself a method of manipulating Yin and Yang attributes, the same principles could naturally be applied to Sage Arts as well.
After all, both were simply different manifestations of energy.
And under Satsuki's mastery of [Energy Control]and the Tenseigan, there were no longer any secrets between them.
"By applying the techniques used to form Yin-Yang Release to the restructuring of Sage Energy, one can achieve an astonishing degree of physical enhancement."
The special form of Sage Art that Satsuki now held was the direct result of that guiding philosophy.
She named it Yin-Yang Sage Art.
Through her experiments with Tenjin Hyūga, Satsuki discovered that this new form of Sage energy amplified the human body far beyond what was possible with ordinary Sage Mode.
Moreover, because the energy inherently contained and balanced two opposing forces, its stability within the human body was exceptional.
Most notably, Tenjin Hyūga displayed none of the usual abnormalities that occurred when one first entered Sage Mode. The only visible change was the appearance of a few faint green markings on his forehead.
Hidden beneath his long black hair, they were barely noticeable.
However, this very stability introduced a new complication: the state could not easily be dispelled.
For Tenjin, this was not a problem—Satsuki could easily extract the energy from his body if needed. But if he were on his own, the power might remain within him until the day he died.
"Tenjin Hyūga," Satsuki said calmly, "I've already developed an idea for further refining natural energy. You may return for now. If you experience any irregularities, report to me immediately. Once the Sage Land reconstruction is complete, I'll summon you again."
As she spoke, Satsuki snapped her fingers, and a black spatial portal opened beside him.
Tenjin rose to his feet, the green lines on his forehead gradually fading away. He bowed respectfully. "Yes, Lady Satsuki."
With that, he stepped into the portal and vanished—reappearing moments later in Uzushiogakure.
Though he had served as an experimental subject over the past two days, the Byakugan had granted him clear insight into the changes occurring within his own body.
Now, he felt an urgent need to adapt to and understand those transformations.
He also realized that if this power proved suitable, Satsuki would undoubtedly extend it to the entire Hyūga clan.
Thus, for the sake of his kin, he had to thoroughly record and analyze every possible effect this new energy might have on the body.
With that determination, Tenjin Hyūga pushed open the door of his assigned residence and made his way toward the training grounds of Uzushiogakure.
Whoosh—
The sound of air splitting echoed faintly as his figure disappeared into the distance.