Tsunade was startled when she heard Oguri Hayashi's words.
She had not expected Oguri Hayashi to know even such things.
Before this, Sage Arts could be said to have been discovered by the Toad Sages. If it were a skill unique to the protagonist, then Kabuto and the First Hokage using Sage Mode later proved that Sage Mode was not exclusive to Naruto. As Shikkotsu Forest's inheritor, it was only natural that Tsunade knew Sage Arts.
Yet from the perspective of the future, she did not know Sage Arts.
Clearly, she had failed to learn Sage Arts. Oguri Hayashi knew this, yet he had asked her about it because he had questions he wanted to consult Tsunade on and could only begin by throwing out a topic.
"You know about Sage Mode too?" Only inheritors of Ryūchi Cave, Shikkotsu Forest, and Mount Myōboku were likely to know of Sage Mode, though it could not be ruled out that there were other ways to learn about it.
"I know a little, but not much. I want to know exactly how Sage Mode works." Oguri Hayashi's ambitions were great, though he did not tell Tsunade so. Still, she could vaguely sense his ambition from his words.
Was he trying to learn Sage Arts?
Mockery appeared on Tsunade's face. "Give it up. Sage Mode is nowhere near as simple as you think. Even among us Three Sannin..."
Tsunade suddenly stopped. Sage Mode was an important secret. Ordinary ninja had never even heard of it, much less understood its power. When Naruto trained in Sage Mode, he could already defeat someone with half of the Nine-Tails' power. In other words, Jiraiya, who possessed Sage Mode, already had the combat power of a Tailed Beast.
Together with Hiruzen Sarutobi and the current Nine-Tails Jinchuriki, Kushina Uzumaki, a single village possessing three fighters of that level was already as secure as a mountain.
Moreover, neither the complete Nine-Tails nor Sage Mode was anything simple. Whether it was the identity of a Nine-Tails Jinchuriki or the user of Sage Mode, both were secrets among secrets within a ninja village. Tsunade would not reveal them so easily.
"I see. So all three of you have already tried it? Is Orochimaru's face like that because of Sage Mode?" Although Orochimaru's ninjutsu was all self-created and looked snake-like, that would not cause snake-scale-like growths to appear on his face and around his eyes. But if it was Sage Arts, that made sense: the aftereffects of being contaminated by Ryūchi Cave's Sage Chakra.
It seemed that Orochimaru had begun studying Jugo because the path of Sage Arts had failed for him.
Jiraiya, who showed no signs of contamination, had succeeded instead.
Sure enough, Jiraiya had been able to become the Third Hokage's disciple because he was a genius in certain respects.
"Can you summon the slug so I can ask it something? I have a few questions about Sage Arts." Like the Rasengan, Sage Arts theoretically had no threshold at all. But in reality, all ninja guarded their secret techniques jealously, terrified that other ninja might learn them. To come into contact with such techniques, one first had to be their direct disciple or a descendant of a direct disciple.
But after giving it some thought, Tsunade realized that even if she gave Sage Arts to Oguri Hayashi, he would be unable to learn it. It required sufficient natural energy, and it was said that such natural energy existed only in Ryūchi Cave, Shikkotsu Forest, and Mount Myōboku. Since that was the case, there was no harm in letting him learn a little about it.
Since Oguri Hayashi knew that Konoha had ninja who practiced Sage Arts, he would probably think twice before acting recklessly.
Without any attempt to hide it, she summoned the slug. The slug had been her method of contacting Konoha these past few days, and she did not conceal the Reverse Summoning Technique from Oguri Hayashi either.
Oguri Hayashi did not stop her.
"Lady Tsunade." The slug looked at Tsunade and asked, "What are your orders?"
"Yes, I have a few things I want to ask you." Oguri Hayashi voiced some of his questions.
He had once believed that the Rasengan required Wind Release Chakra to train, but in fact, Chakra of any nature could be used to practice the Rasengan and incorporate changes in Chakra nature. That was when he realized that his memories could not serve as absolute truth. While his memories allowed him to recall most of Naruto's plot, when it came to actual ninjutsu training, he still needed to unite knowledge and action and train according to real circumstances.
It was like in History's Strongest Disciple Kenichi, where only the harshest training and the greatest talent allowed Martial Arts Masters to achieve Unity of Motion and Stillness, the union of the qi of motion and stillness.
Yet after obtaining the manual, Oguri Hayashi had found another path. He cultivated still qi within himself and transformed Lightning Chakra into the qi of motion, easily completing a Unity of Motion and Stillness. This made him understand that while a manual was still a manual, one needed one's own ideas and methods for how to practice it.
Wisdom could make his training twice as effective with half the effort, but even so, some things had to be adapted to reality.
For example, Sage Arts.
Though Sage Arts were useful, they were not what Oguri Hayashi needed. Judging purely by the most direct measure of combat power, Naruto's combat strength after completing Sage Mode exceeded half the Nine-Tails' Chakra. Yet every generation of Raikage had been capable of directly suppressing the Eight-Tails.
By a straightforward comparison of combat power, his own path was clearly stronger than Sage Mode.
Of course, adding Sage Mode to it would indeed unleash tremendous power, but Sage Mode's risks were rather great.
He merely needed the slug to resolve some of his doubts.
After all, how similar was so-called Sage Mode to the Unity of Heaven and Man emphasized in martial arts in China?
Invincible Superman Hayato Furinji's [My Style] also mentioned that martial arts' ultimate concept should be the ability to sense nature and achieve Unity of Heaven and Man.
In truth, Invincible Superman had at times already come extremely close to that state, and martial arts in China had also repeatedly mentioned concepts such as the resonance between Heaven and Man and Unity of Heaven and Man.
If it could truly be proven that Chakra's Sage Mode and Unity of Heaven and Man were the same concept, then Oguri Hayashi would know what his path forward should be.
Since he was Tsunade's "friend," the slug naturally answered every one of Oguri Hayashi's questions. Oguri Hayashi's understanding of Sage Arts became clearer and clearer, and the concept of Sage Mode in his mind grew increasingly defined.
"I see. I understand a little now." A thoughtful expression appeared on Oguri Hayashi's face. He nodded. "Thank you, slug."
"Not at all."
The slug waved its feelers. "Then, Lady Tsunade, if there is nothing else, I will return first."
"Mm, go back," Tsunade said. Watching the slug vanish into white smoke, she turned to Oguri Hayashi and asked, "What did you understand?"
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