Few things could truly shock the Third Hokage. He had lived too long and seen too many things, wonders and horrors alike.
But today, he was gobsmacked as he watched Naruto pour chakra into the little plant that Hiruzen had given him, making it swell.
He had hardly believed it when the ANBU guards had reported it to him, wondering if his subordinates had been ensnared by some genjutsu.
But now that he was here, in Naruto's apartment, watching his surrogate grandson enhance a plant with chakra…they had been right.
Masking his shock as best as he could, Sarutobi smiled at Naruto, who was waiting for a response, clearly excited.
"That is very impressive, Naruto," The Professor said, and he meant it. "But tell me, how in the world did you do it?"
"I just poured kachra-" Sarutobi suppressed a sigh at the mispronunciation. "-into the plant! Iruka-sensei was talking today about how you can make things stronger by putting chakra in them, and so I tried it out."
Sarutobi was silent for a moment as he absorbed this.
That…made absolutely no sense.
Chakra flow was a well-known technique, of course, but this wasn't how it worked. Not only did it require the sort of chakra control and precision most shinobi did not develop until they were chunin (a level of precision Naruto most certainly did not have), but there were limits to it.
It was possible to channel chakra into an ordinary kunai, but no matter how skilled the user, the fact was normal metals would ultimately break under the pressure of too much chakra. Chakra conductive metals were preferred not only because they could enhance the power of a technique, but also simply because they could actually last.
And that was for inorganic materials only. With organic creatures, injecting your chakra into it accomplished little other than increasing the target's chakra levels. To actually heal and revitalize a living thing as Naruto claimed to have done to the plant required medical ninjutsu. There were some exceptions, such as the incredibly toxic chakra of the Biju, but that was an example of adverse effects, not negative effects.
Seeing that Naruto was still waiting for a response, Sarutobi collected his thoughts. "How about we test this out a little more, hmm? Perhaps you can do more than simply revitalize Mr. Ukki."
Subtly, Hiruzen conjured a shadow clone on a nearby rooftop, which set off to clear his schedule for the day.
He needed to run more tests. It was possible, though unlikely, that this new ability of Naruto was not Mokuton but merely something similar.
But if it was, Hiruzen had to be absolutely sure.
"But I don't think this is the best place for it, Naruto," Hiruzen continued. "I know a better place for it, which I think you will like."
"What kind of place?" Naruto asked inquisitively.
"A secret training ground," Sarutobi said, lowering his voice. "One only for Hokages."
After that, it was not too difficult to take Naruto to the training ground Minato and Jiraiya had once favoured for their own.
Naruto looked around at the various training dummies and equipment with wide-eyed excitement, but that wasn't why Sarutobi had brought him here. All those were tools were designed for Jonin-level ninjas at minimum, not an eight-year-old Academy Student.
What was more important was this training ground was secluded and private, as well as being close to the forest, which meant that he could test Naruto's new ability in peace without interruption.
"Now, Naruto, I have a few ideas for how we can test this…"
"This changes everything."
"Thank you for your insight, Homura," Koharu sniped. "We all know that."
Sarutobi said nothing as his two old teammates bickered, his eyes focused on the full moon outside.
For nearly a day, he had conducted every possible test he could think of with Naruto's new ability.
Making flowers bloom, strengthening trees, manipulating leaves…it was Mokuton, there was no doubt.
"-The question is, how did a below-average academy student recreate Mokuton where so many others have failed?" Homura finished.
"I am not sure," Hiruzen said finally. "I had long suspected that there was some unknown element to Lord Hashirama's Mokuton, and I suspect that same element is in play here."
"Yang Release," Koharu mused. She had heard theories before, from him and Tobirama-sensei.
"Most likely," Hiruzen agreed. "Naruto has no idea how to knead Suiton and Doton, much less combine them. No, what he did is different."
Mokuton had always been different from other elemental release techniques, even beyond the obvious. Ultimately, essentially every other form of elemental technique that Hiruzen was aware of involved creating and manipulating inanimate matter. The five basic elements, bloodlines such as lava and ice, and more.
But Mokuton alone was an elemental bloodline that could create life. It did not do so if the wielder did not desire it, but the mere fact that it was capable of creating living things was extraordinary.
There had to be something else to add to the equation, and Yang was the most obvious answer. Indeed, it was the only answer.
Hiruzen could not say for certain, but Lord Hashirama was long dead and could not answer. Not to mention the man had been essentially forced to develop his techniques from scratch and by instinct, lacking any true guide except a handful of obscure myths about other wielders of Mokuton in the past that could not even be verified.
"We will have time to consider the how and study the boy's abilities later," Koharu interrupted his train of thought. "The most important question is, what are we going to do about the boy?"
Hiruzen resisted the urge to sigh as both his teammates fixed their gazes on him.
"He must be trained," He said finally, reluctant to even say but unable to deny the truth. "On how to wield Mokuton and how to conceal it."
"Indeed." Koharu agreed, clearly pleased that Hiruzen was not fighting him on the topic as he had before. His councillors had long wanted him to push for a harsher, more rigorous training regime for Naruto, to strip away what tattered remnants of a childhood he had.
They both counted his concession as a victory.
Unfortunately, Hiruzen saw little other choice. The power and potential of Mokuton were far too great.
And Mokuton was not merely a weapon. It was a weapon, of course, and a potent one at that, but it was so much more.
The First Hokage was remembered primarily for his subjugation of the Biju, for the incredible might that no one save Uchiha Madara had even come close to matching.
People remembered the armies he had slaughtered, the landscapes he had reshaped and the fear that he had brought.
But Hashirama had done so much more with Mokuton than merely wreak destruction upon his enemies. The first buildings in Konoha, the very core of the village, had been built by him. The forests around Konoha, though they had existed long before the First Hokage's birth, had been strengthened, expanded and revitalized by Mokuton, making them able to support many of Konoha's needs.
Mokuton was as much a tool of creation as it was a weapon of destruction, and the uses for it were boundless.
It was simply not something that could be left for later, not least because Sarutobi was certain Naruto would experiment with the ability on his own.
"The question is, how to train him?" Homura mused.
"Assembling a team of instructors and creating a program to accelerate his education should not be too difficult," Koharu said. It was what she had always wanted, for Naruto to be treated as a soldier from birth.
She was not as hawkish as Danzo, who had wanted Naruto for his own or at least inducted into ANBU as soon as possible. Koharu recognized that doing that was more likely to create an emotionally and mentally unstable jinchuriki than a useful soldier.
But she had also always thought that Hiruzen's handling of the boy was too soft.
"I am uncertain that is the best way," Homura disagreed. "The boy must be trained, but his ability will make him a target. Too many people knowing about his ability is a risk that we cannot afford until."
While the words were helpful, Hiruzen knew better than to think that Homura was speaking out of any real concern for Naruto himself. His focus was ultimately on ensuring something as valuable as Mokuton was not stolen from them.
Nevertheless, Koharu conceded the point grudgingly. "A tutor, then. Someone who can be trusted to keep their mouth shut but will train the boy well."
There was a moment of silence as they all considered the options.
"Danzo will want him," Homura said, an undercurrent of disdain bleeding into his voice.
"Danzo has always wanted him," Koharu said sharply. "But Danzo would only ruin the boy, leave us with a rabid dog like Suna's jinchuriki at best."
"He will not go to Danzo," Sarutobi said, genuine anger leaking into his voice for the first time. "And this will remain secret from for as long as possible. If either of you tell him, I will consider it treasonous exposure of an S-Class secret."
Koharu and Homura both stared at him, a little wide-eyed, but Sarutobi could not find it in himself to care. He was still furious with his former friend's handling of the Uchiha, and the idea of giving Naruto to him was unthinkable.
"I wasn't suggesting we give him the boy," Homura said placatingly, watching Hiruzen a little warily. "Merely that it is something we have to acknowledge. We cannot keep the boy's abilities a secret forever."
Sarutobi conceded the point with a sour nod.
Clearing her throat, Koharu returned to the original topic. "So, a tutor. Who?"
"I believe Tenzo would be the best choice," Hiruzen said, unwilling to let either of his former teammates even raise their suggestions. "He is the only other person in the village with any true experience with Mokuton, and that makes him ideal.
Homura frowned thoughtfully, but Koharu scoffed. "Tenzo has not been nearly as successful as he should be. I should hope you do not wish for the boy to follow in his footsteps."
Koharu's expectations of Tenzo were, of course, entirely unfair. Tenzo was a perfectly capable jonin-level ninja and had excelled in his duties as part of ANBU.
But what Koharu had wanted from Tenzo, and what she now wanted from Naruto, was a second coming of Hashirama, not merely a capable jonin with some unique abilities.
"We do not yet know the full extent of Naruto's abilities," Hiruzen said evenly. "His Mokuton may not be as potent as Lord Hashirama's. Even if it is, it will take time to master, and Tenzo is the one best suited to such a task. It is not as if we have a variety of Mokuton masters to pick from for Naruto's tutor."
Koharu scowled but nodded grudgingly. "His experiences will be useful, at least."
"Tenzo it is, then," Hiruzen said after a long moment when his councillors voiced no other objections. "I will summon him and give him his new mission tomorrow."
After his two teammates had left, Hiruzen let out a long sigh, leaning back in his chair and taking a deep breath from his pipe.
Despite his words to Koharu, Hiruzen could not help but privately hope that Naruto truly did possess the same Mokuton as the First Hokage. If he did, it would make taming the Kyubi a far easier prospect.
Konoha had never deployed a jinchuriki on the battlefield. Not, Sarutobi admitted to himself, out of any particular ethical concerns but simply because it wasn't possible.
The Kyubi had been so vast and overwhelmingly powerful that even Lady Mito's seal had been barely enough to contain it. After Lord Hashirama had died, she was forced to remain within Konoha, within a tower specially designed to strengthen her seal and ensure the Kyubi could not escape.
Kushina had been subject to the same fate after becoming a jinchuriki, living a lonely life within the tower until she and Minato had devised a way to strengthen her seal.
But even then, there had been limits. Once she had been able to move freely outside the confines of the barrier, Kushina had proven a talented and capable kunoichi, Sarutobi had blocked all attempts to have her learn to wield the Kyubi's powers.
Improved or not, Minato and Kushina's improved version of the seal had ultimately been experimental, and he had not judged it worth the risk to have her learn to wield the Kyubi's chakra. The chances of the beast breaking free were simply too high.
Naruto's seal was different. It was even stronger than Kushina's, forged with the aid of the Shinigami as it was. Jiraiya had looked it over and theorized that Minato had intended for Naruto to be able to wield Kyubi's power one day.
Despite Danzo's agitation otherwise, Hiruzen had always been reluctant to pursue the idea. Not only did Konoha have no idea how to train a jinchuriki, it was not as if the methods of the other villages had proven effective. Hiruzen had heard of what the current Kazekage had done to his son, and all it had produced was a child driven mad by not just the beast he contained but the horrors heaped on him.
Not to mention the infamous rampages of the Hachibi through Kumo. They had stopped ever since the latest container Killer B, had the beast sealed within him but that was after several generations of jinchuriki dying and the Hachibi rampaging across Konoha. If not for the incredible might of the Third Raikage, Kumo would have died long ago.
But even the Kyubi had fallen to the might of Mokuton in the end, and that had been without a seal as strong and refined as the one Naruto possessed.
It was indeed possible that Naruto might be able to wield the power of the greatest of the Biju one day.
But more importantly than that, if Naruto ever achieved even a fraction of Lord Hashirama's ability to subdue the Biju, it exponentially increased the chances that the boy Hiruzen had come to love as his grandson would remain sane and stable, never losing himself to the power and madness of the creature within him.
And that, ultimately, was more important than anything else. Hiruzen had already failed Naruto in countless ways.
The least he owed him was to give him the best possible chance at a happy life.