Deep beneath the Hokage Building, in a hidden underground space, Yunchuan Hyuga followed the guidance of a scroll. He soon reached a door at the end of a long corridor.
There were no guards outside, yet he could clearly sense the presence of a Sealing Technique and a Barrier Technique. Even a mosquito flying in would instantly trigger alarms and defensive measures.
It was hard to imagine how Naruto Uzumaki had managed to steal the Book of Seals under Mizuki's instigation. But thinking of how Orochimaru had once broken in here, and how Mizuki was a piece placed by Orochimaru in Konoha, it no longer seemed impossible.
Yunchuan Hyuga did not need to go through such trouble. When he took out the scroll given by Hiruzen Sarutobi, the feeling of restriction vanished at once. With a light push, he opened the door to the Forbidden Technique Vault.
kacha. As he stepped into the silent Forbidden Technique Vault, dust on the floor was stirred by the air, and the candles in the room lit themselves.
The walls had no windows, and tall shelves stood in neat rows before them. Each shelf was filled with carefully arranged scrolls, sealed and labeled by rank, looking old and heavy under the flickering candlelight.
"It seems that the one known as the 'Ninjutsu professor,' the Third Hokage, comes here often," Yunchuan Hyuga thought. The shelves and scrolls were old but clean, which made it obvious.
At the same time, he felt a faint sense of being watched. Was this Hiruzen Sarutobi's long-distance viewing technique?
This Ninjutsu used a special crystal ball as its core, relying on precise Chakra control to analyze fluctuations and transmit images over great distances. Hiruzen Sarutobi often used it for what he called "protective observation" of Naruto Uzumaki.
The great toad sage of Mount Myoboku used a similar method, though its range clearly surpassed normal limits. Even though it was only for reconnaissance and not combat, it was undeniably convenient.
Yunchuan Hyuga sighed inwardly but kept his expression calm. As his eyes swept across the shelves, he even showed a hint of open surprise, like someone seeing a vast collection for the first time.
He casually pulled out a scroll and unrolled it. The material was smooth, packed with dense handwritten text and a few diagrams.
It recorded a technique called Fire Release: Ash Pile Burning, an ordinary B-rank Fire Release Ninjutsu. Of course, that "ordinary" was only from Yunchuan Hyuga's perspective.
Techniques were divided into six learning levels. E-rank was the entry level taught at the Ninja Academy, such as the Substitution, Clone, and Transformation techniques, along with skills like Stealth and Escape that were closer to technique than true Ninjutsu.
D-rank corresponded to the Genin level. The Binding Technique was often the only D-rank Ninjutsu an average ninja learned during academy days, while C-rank reached the Chunin level and already carried real difficulty, such as Summoning Jutsu and puppet techniques.
B-rank Ninjutsu belonged to the Jonin level and were considered valuable even among the Five Great Villages. Even the Lightning Release Armor used by the Raikage was only at this level, so placing such a technique here was reasonable.
Yunchuan Hyuga skimmed through it without much interest and soon returned the scroll to the shelf. He continued browsing several more, most of them B-rank Wind Release Ninjutsu and Taijutsu.
There were techniques like Front Lotus, Wind Release Shuriken Production, Wind Release Great Kamaitachi, Wind Release Pressure Harm, and Wind Release Vacuum Great Sphere. After a quick glance, Yunchuan Hyuga's eyelid twitched slightly.
"This is way too obvious," he thought, and put them back without hesitation. Only a few rare techniques made him pause, such as Summoning Jutsu combined with Gate of Life, Adamantine Sealing Chains, and Shadow Strangle.
"Not a single Forbidden Technique left for me, yet they did not take away the secret techniques of other clans." Yunchuan Hyuga smiled inwardly. "Do they really think I cannot learn them?"
That assumption was not unreasonable, since the line between secret techniques and Kekkei Genkai was often blurred. Techniques like the shadow techniques of the Nara Clan or the Adamantine Sealing Chains of the Uzumaki clan did not come directly from blood at birth, but without special talent they were nearly impossible to master.
The Nara Clan were born with stronger spiritual energy, while the Akimichi Clan possessed greater physical energy. That was why they could inherit their clan techniques and master Baika no Jutsu.
The Uzumaki clan was the same. According to Uzumaki Mito, Uzumaki Kushina was chosen as a jinchuriki because she had a rare and special talent.
Only a few individuals in the Uzumaki clan could learn Adamantine Sealing Chains. They were naturally suited to restrain tailed beasts and become jinchuriki.
These secret technique clans felt like a lower tier of Bloodline Inheritance clans. Through long-term intermarriage, their bloodlines were refined, and war further filtered those with stronger traits.
Over time, stable special physiques appeared, and special Ninjutsu were developed around them, forming secret technique clans. Given a few hundred more years of intermarriage, they might even evolve into true Kekkei Genkai that required no learning at all.
Unfortunately for them, Yunchuan Hyuga's current body was, by bloodline standards, the ancestor of all these clans.
Yunchuan Hyuga felt that this body of his could fully handle the secret techniques of those ninja clans. He did not rush to try them, only pausing for a few minutes before putting the techniques back and looking at other scrolls. His movements were calm and deliberate, with no sign of impatience.
He carefully memorized the positions of every scroll that interested him. To an outsider, it would look like he was grabbing things at random and discarding them just as quickly. In truth, he was committing everything to memory as he went.
Eventually, Yunchuan Hyuga walked to the deepest shelf and reached for the highest level, taking down the two scrolls that looked the newest and the most ancient. When he opened them and swept his eyes across the contents, his gaze narrowed without him noticing. A faint smile appeared at the corner of his mouth.
Hiruzen Sarutobi really did leave behind good things.
"Lightning Cutter?"
"Yin Seal?"
A look of open delight appeared on his face as he sat cross-legged and placed the scrolls in front of him to read carefully. This scene caused the man currently sitting in the Hokage Office, watching through the Crystal Ball, to frown slightly. Hiruzen Sarutobi let out a quiet sigh.
"As expected, still too young and a bit restless," he muttered to himself.
The truly powerful Ninjutsu were all recorded in the Book of Seals. That book held not only S-rank forbidden techniques, secret arts, and Sealing Techniques, but also A-rank Ninjutsu like Multiple Shadow Clone Technique. Naturally, Hiruzen Sarutobi would never leave the Book of Seals in a place like this.
In his view, some B-rank Ninjutsu were already extremely valuable for Yunchuan Hyuga. Out in the open world, if a small or mid-sized force obtained a B-rank Ninjutsu, it could easily bring disaster upon them. It might even attract the bandits from Kumogakure.
If he had not seen Yunchuan Hyuga's talent in Ninjutsu, and if the boy's recent performance had not been so striking, Root would never have opened the Forbidden Techniques Vault to him. As for why Lightning Cutter and Yin Seal were placed here, there was a trace of hope mixed in, but mostly it was meant as a test of Yunchuan Hyuga's temperament. Hiruzen Sarutobi wanted to see what choice he would make.