One Piece: Take the Uchiha Clan to the Grand Line

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"Sensei, you haven't been slacking all these years, huh? Your strength has improved a lot since back then!"

"You're one to talk! You've become downright monstrous compared to before!" Orochimaru said.

Orochimaru could tell that Uchiha Kitaro hadn't even started using the powers he'd shown earlier.

Just with breathing techniques and swordsmanship, this little monster had blocked all his attacks.

Now, this "little monster" had fully grown into a big one.

Crackle! Zap!

The flames surrounding Kitaro's body extinguished, and lightning flickered around him.

"Next up is the Thunder Breathing technique. My speed might get crazy fast, so watch out, Orochimaru-sensei."

With a flash of lightning, Kitaro attacked Orochimaru with Thunder Breathing-style sword techniques.

His incredible speed made Orochimaru's hair stand on end. Even with his skills, dodging attacks that fast was nearly impossible.

Afterward, Kitaro seamlessly shifted into Water Breathing, then Wind Breathing, followed by Stone Breathing. By the time he cycled through all five major Breathing styles, Orochimaru was a mess—covered in injuries and forced to shed his skin again to recover.

The look Orochimaru gave Kitaro now was one of shock and disbelief.

He'd heard the stories of his student earning the title of Sword God but never imagined his swordsmanship would be this terrifying. The sheer mastery of it alone was enough to put him among the strongest warriors.

"These are the Breathing Techniques. Aside from the five basic styles, there are also derivative techniques like Serpent Breathing, Mist Breathing, Sound Breathing, Love Breathing, Insect Breathing, Flower Breathing…"

"Then there's Moon Breathing… and the most powerful of all, Sun Breathing."

Orochimaru was stunned. So many styles? This was practically an entirely new combat system on par with ninjutsu!

"Breathing Techniques greatly enhance a person's physical abilities. Especially if you fully replace normal breathing with Breathing Techniques, your body will gradually grow stronger over time, until you reach your physical limits."

"And when you reach a high enough mastery of these techniques, you can unlock two special states."

"The first is called the Transparent World. It's a supreme realm you can only achieve by pushing yourself to the limit and enduring intense pain."

"In this state, by focusing and shutting off unnecessary senses, a person's body appears almost transparent. Movement speed, attack prediction, and evasion all improve significantly. You can even see the blood flow in an opponent's lungs and feel the contraction of their muscles with precision."

"You can also turn off your own aura entirely, making it easier to confuse or outmaneuver your enemy. Since your perception accelerates, their movements will appear slower."

"…"

Kakashi and Guy were both stunned. They'd only just started learning the basics of Breathing Techniques, and Kitaro's descriptions made it clear they were still light-years away from reaching such heights.

Still, what he described was nothing short of awe-inspiring.

"Once you've gone even deeper into mastery, you can awaken Marks," Kitaro continued. As he spoke, a pattern of three tomoe appeared on the left side of his forehead.

"To activate these Marks, your body temperature needs to reach 39°C, and your heart rate must exceed 200 beats per minute. Of course, this puts a massive strain on your body."

"But once activated, these Marks give you a significant boost in combat ability."

"…"

Orochimaru's heartbeat quickened. He wanted everything Kitaro was offering. Initially, he thought he'd only gain a small piece of knowledge, but Kitaro had just revealed three entirely new systems beyond conventional ninjutsu.

The Haki system, which was undeniably powerful. In terms of overall combat capability, it might even surpass traditional ninja techniques, though top-tier ninjas might still hold the edge in raw strength.

The Breathing Techniques and swordsmanship system, which could enhance physical attributes—something Orochimaru understood better than anyone else to be invaluable. In game terms, it was like upgrading your core stats, far more essential than simply leveling up skills.

Each of Kitaro's sword styles had immense potential, and with so many ninjas already using weapons, integrating these techniques could be revolutionary. Orochimaru's own Kusanagi Sword would be perfect for this.

While these two systems were incredibly powerful, Orochimaru didn't see them as having high research value.

What really intrigued him was the so-called Devil Fruits. However, judging by Kitaro's tone, they were rare and precious—not something easily obtained.

"Oh, by the way, there's one more thing."

"One more thing?!"

Was this guy a bottomless pit of abilities? How could he still have more to offer?

"This last one isn't a technique or a skill. It's more of an ability, I guess."

"Orochimaru-sensei… do you want to live forever?"

Orochimaru's pupils shrank, and he locked eyes with Kitaro. "What did you just say?!"

"I know you've always been chasing immortality, sensei. I wasn't really pursuing it, but I kind of stumbled upon the ability. I'm not sure about true immortality, but living for ten thousand years? That's no problem."

Ten thousand years was actually Kitaro being modest. He felt like he could live forever, but that would sound too ridiculous.

"That's impossible!!!"

Everyone was dumbfounded. Even Shisui and Itachi had no idea about this. It wasn't that Kitaro had been keeping it a secret—he just knew how outrageous it sounded. Many already thought of him as a monster; he didn't need to make himself even more terrifying.

Orochimaru, too, was in disbelief. His Immortality Jutsu allowed him to inhabit other bodies, but it came at a cost. The bodies aged rapidly, and his life was constantly at risk unless he transferred to a new host.

Every transfer took a heavy toll on his mind, and he doubted he could do it more than ten times. At best, it might give him three to five hundred years, but he believed that within that time, he could develop even better techniques.

But living for ten thousand years? That was beyond the limits of life itself. Not even tailed beasts lived that long.

"Are you serious?!"

"Of course! You know me, sensei—I never lie."

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