Naruto: We are invincible

He walked up to Sai and began searching his memory, and soon found relevant information.

"A simple paralysis seal, using Danzo's chakra as the key, to prevent him from revealing secrets." Naruto thought to himself as he squatted down in front of Sai.

He slowly opened his mouth and stuck out his tongue, revealing a black mark at the base of his tongue.

"Unlock!" Naruto pressed two fingers on the black mark and injected chakra into it, trying to unlock the seal.

The seal began to smoke and eventually disappeared completely.

At the same time, the black mark on Sai's body disappeared and he regained his ability to move.

"Your master is Danzo, right?" Naruto asked, and Sai nodded. He had now completely given up resistance.

He knew that there was no way he could resist Naruto.

Naruto could flip through his memories at will and find the answers he wanted in an instant.

"So, who sent Danzo-sama to assassinate us?"

"It's the Fifth Hokage, Senju Tsunade." Naruto smiled after hearing Sai's answer.

"So, logically speaking, you serve the Hokage of Konoha and follow her orders, right?" Naruto asked. Sai nodded.

"But you tried to kill me, the leader of the Senju clan, and Hinata, one of Konoha's best medical ninjas." Naruto continued, "As a ninja of Konoha, what do you think this means?"

"Traitor..." Sai said in disbelief, "But... this is an order from my superior."

"So, logically speaking, your boss is a traitor to Konoha, right?" Naruto asked. Sai nodded again, betraying everything he had always believed in.

"Since you knew that assassinating us would constitute treason, why did you do it?" Naruto asked.

Sai showed a confused expression for the first time.

"In the Root organization, there are no names, no emotions, no past, and no future, only missions." Sai said in a calm tone, and it was obvious that this sentence had been deeply imprinted in his mind.

"Is this why you betrayed Konoha? You feel no emotions and you can't tell right from wrong. You just follow orders without a second thought, even if they go against your own beliefs," Naruto explained.

But Sai remained silent.

Naruto walked up to him and placed two fingers on his forehead:

"Well, you should rest for a while. I'll come talk to you again when we get back to Konoha."

Sai slowly closed his eyes and fell into a deep sleep.

## The Library of the Senju Clan ##

A few seconds later, Naruto returned to Konoha Village.

He went straight to the library of the Senju clan.

Since Hinata wasn't around, he had to find a way to find the area where the books on human biology were kept on his own.

When he found the area, his jaw dropped.

This place is simply too big, and the bookshelves are filled with densely packed books covering human anatomy, skeletal system, tissue systems, cell biology, and so on.

The area with the reptile biology books was dwarfed by this.

This is enough to prove that the Senju clan's research on the human body has reached an astonishing depth.

This is not surprising. After all, for thousands of years, countless people have dreamed of breaking the limits of the human body and creating a perfect body, perfect weapons, and a perfect ninja with unparalleled strength, speed, and chakra.

Although many people are studying how to push the limits of the human body, only a few can actually do it.

For example, Tsunade Senju created a sealing technique that can greatly improve cell regeneration ability by sacrificing lifespan.

However, there is a limit to the number of times a cell can divide, and once this limit is exceeded, the user's life span will be shortened.

Another genius, or madman, Orochimaru, has also made great achievements in this area.

Although he was cruel, evil and did not take human life seriously, he was indeed a rare medical genius.

Like Orochimaru, others are also trying to find ways to break through the limits of the human body.

He invented a seal that can infuse natural energy into the human body, thereby gaining powerful strength.

But natural energy is not easy to control. Among all the ninjas, only a very few can withstand and use natural energy, and among them only three can become immortals perfectly.

Naruto was looking for something similar.

Although his knowledge in this area is not as rich as that of Tsunade, Hinata and Orochimaru, he also has his own advantages, namely the Rinnegan and Yin-Yang escape.

He does not need to master too much knowledge to create what he wants, because everything he thinks about can become reality.

"This will take time..." Naruto sighed, coming out of his reverie and began searching the bookshelf for the book he wanted.

"Naruto? Is that you?" Naruto heard the voice, turned around and saw Tsunade walking towards him.

"Why are you here? Shouldn't you be in the Hidden Cloud Village?" Tsunade was very surprised to see Naruto appear in the library.

"I'm just here to check some information. By the way, Hinata and I have passed the second exam and successfully advanced to the third round." Naruto said as he flipped through the book in his hand.

"I knew you would be fine." Tsunade said with a smile, a proud look on her face.

"Are Sai and the others okay?" She noticed the serious expression on Naruto's face.

"Shikamaru and the others haven't finished the second exam yet, and as for Sai… he tried to kill us while we were sleeping."

"What?!" Tsunade roared.

"That was Danzo's mission. Protecting the heir of the Senju clan and the Nine-Tails Jinchuriki was just a cover to hide his true intentions." Naruto explained, "I don't know why he wanted to kill Hinata and me."

"When I catch that pretty boy and his old master, I will..." Tsunade said gritting her teeth, her knuckles crackling as if she was going to crush something.

"It's not Sai's fault," Naruto said calmly, his brows furrowed slightly.

"Are you trying to plead for him?" Tsunade asked in disbelief.

Assassinating the successor to the Hokage is a serious crime, second only to assassinating the Hokage himself, and is punishable by death.

"I checked his memory. He was just a tool being manipulated." Naruto said sadly, "To him, it was just an order, nothing more."

"I'm not interested in tools that only follow orders." Tsunade said coldly and Naruto was shocked by her attitude.

"Don't you think it's too cruel of you to say that?"

"I can say the same about you. You are not the type to show mercy to your enemies." Tsunade said sternly.

"I said, he's not an enemy, he's a comrade," Naruto insisted.

"A companion who tried to kill you while you were sleeping?" Tsunade snorted and retorted. She wondered in her heart, Naruto was not the kind of person who would easily forgive his enemies, what made him defend Sai so much?