The Mastermind

Using the Mangekyō Sharingan's ocular techniques for the first time, the chakra consumption was secondary—the real issue was the immense mental strain. His eyes and body had only just begun to adjust to each other and had not fully stabilized, so Mizuki's left eye ached intensely after he used Kotoamatsukami.

After treatment, the rampaging Mangekyō Sharingan finally settled down, and that nagging illusion that he might go blind vanished as well.

"It really is troublesome. Without Uchiha blood, using the Mangekyō Sharingan comes with so many problems."

The Byakugan was actually even less compatible with non-Hyuga people. This ocular technique was not native to the Shinobi World at all, but inherited from the bloodline of the outsider Kaguya Otsutsuki, making it even more alien to the natives of the Shinobi World. Yet once the Byakugan stabilized, it was nowhere near as demanding as the Sharingan.

Of course, advancing toward higher-level ocular techniques was never easy either.

For that very reason, Mizuki, who had originally wanted to properly experience the Mangekyō Sharingan's power, decisively performed another operation, removed the Sharingan, and replaced it with his own eyes.

"Original parts are still the most comfortable."

Mizuki let out a long breath. He truly could not get used to that perspective, like looking through a faint red mist.

During this time, Orochimaru did not say anything unnecessary. He merely watched Mizuki work in silence. Others might have found Mizuki's strange behavior baffling, but to Orochimaru, it was perfectly normal.

"Now that you're done, can you tell me what exactly I'm supposed to do? You went to such lengths to find me, so there must be a reason why I'm indispensable, right?"

"More or less."

Mizuki roughly estimated the time. Whether it was the eye transplant surgery, testing Shisui Uchiha's Mangekyō Sharingan abilities, or