Happiness always passed quickly; in the blink of an eye, half a year had gone by.
In the far eastern corner of the village, there was a hidden research base belonging to Orochimaru and Shin. The base was built underground, consisting of two floors, each about 3,000 square meters. Research topics included various medicinal herbs, chakra metals, vitality studies, improvements to ninjutsu, and even research on the puppet techniques and organizational systems of Suna.
Inside one sealed room, which could only be accessed through a secret passage, there was a hidden elevator.
A hundred meters below the elevator, there was an even larger space.
This space was 10,000 square meters and also had two floors, with each floor divided into four zones, each dedicated to a different area of research.
This was where the real secrets lay.
Other than Shin, Tsunade, and Orochimaru, no one else knew of its existence.
The eight research zones were dedicated to eight different fields:
Sharingan Evolution Research.
Hashirama Cell Research.
Genetic Modification Research.
Ninjutsu and Forbidden Techniques Research.
Senjutsu Research.
Kekkei Genkai Research.
Soul Enhancement Research.
Immortality Research.
Each one of these areas explored concepts far beyond the common understanding of the shinobi world—and all of them had already yielded abundant results.
Inside the Sharingan Evolution Lab, Shin lay on an operating table. Tsunade was carefully re-implanting his Mangekyō Sharingan into his eyes.
With her use of the Creation Rebirth and a rudimentary version of the Revitalization Technique, she meticulously repaired every severed nerve.
Once finished, Shin sat up.
"Still can't see?" Tsunade asked anxiously, clenching her fists.
"It's been almost a month, how are you still not used to it?" Shin replied with a smile. Though his eyes were closed, his hand reached out and precisely touched Tsunade's cheek.
"Don't worry. The research already has a clear direction. In at most a year, my vision will be restored, and I'll never have to worry about going blind again. The only regret is that I won't be able to see your face for quite a while."
"You still have the heart to joke?" Tsunade punched him lightly, a touch of sorrow in her voice. She was once again on the verge of tears. She had lost count of how many times she had cried over the past month.
"Don't cry, I'm really okay!" Shin quickly pulled her into a hug to comfort her. He regretted using the Mangekyō Sharingan so frequently, it had caused Tsunade so much pain. That was his fault. But he wasn't lying about the potential for recovery. If he hadn't been absolutely confident, he never would have taken such drastic steps.
"Are you really sure your eyes can recover?" Tsunade asked again, her tone extremely serious after calming down a bit.
This was her 72nd time asking, the average was three times a day.
"They really can," Shin answered with the same gentle patience as always.
Reassured once more, Tsunade relaxed a little. She picked up a satin band and carefully wrapped it around Shin's eyes.
"You promised me you wouldn't hurt yourself again," she muttered sadly.
"Uh... what I said was that I'd be more careful!" Shin corrected her. "But I couldn't help it. My eyes are just too valuable for our research."
The abilities of the Mangekyō Sharingan were deeply connected to one's spirit and will. In other words, the powers reflected the deepest and most persistent desires of the wielder.
Obito constantly longed to escape the painful world around him and live in a perfect one without suffering.
Hence, Kamui enabled phasing, teleportation, and access to a personal dimension.
Shisui witnessed his clan's internal divisions, factions, and even plots to stage a coup. Having already been brainwashed, he prayed day and night for his people to find unity, reconcile with Konoha's leadership, and preserve the Will of Fire. Thus, he awakened the most powerful genjutsu, Kotoamatsukami, which could alter another person's will.
Itachi's personality was relatively more complex. From a young age, he too witnessed the internal strife within the clan and the growing tension between the Uchiha and the village. This made him want to destroy the root of it all, which gave birth to Amaterasu, the black flames that could burn everything to ashes. However, he was also deeply influenced by Shisui over a long period of time, and he fantasized about gaining enough power to steer the fate of the clan himself. As a result, his other eye awakened Tsukuyomi, a genjutsu that allowed him to control all aspects of time, space, and even mass within an illusory world.
As for Shin, after awakening his Mangekyō Sharingan, he too gained two abilities. He named the ability in his left eye "Kaiseki." By activating his eye, he could replicate anything he saw and store it in a unique analysis space.
Within this space, he could perform unlimited analytical dissections of the replicated subject.
Simply put, whether it was a person or an object, if he used his eye to look at it, and as long as he wished to, he could create a perfect replica within the analysis space and thoroughly understand its every secret.
Kaiseki could not inflict any actual harm on the subject, it was solely for replication and examination. But he absolutely loved this left eye, because it granted him the power he had always dreamed of.
Over the past six months, his ability to manage eight different research projects, all yielding rich results, wasn't just thanks to Tobirama's talents or Orochimaru's assistance. His left eye had been a major contributor.
So long as he desired it, he could effortlessly uncover the deepest secrets and nature of any person or object. And if he didn't understand at first glance, he could just analyze it repeatedly in his analysis space. With his talent, he would eventually decipher everything.
For example, if he wanted to learn the Lightning Release Chakra Mode, he only had to use his eye on the Third Raikage while he was using the technique, replicate it into the analysis space, and analyze it repeatedly. Before long, he would understand every detail of the technique.
The Sharingan's original copying ability had many limitations.
In truth, what it copied wasn't exactly ninjutsu, it was more about mimicking physical movements and chakra flow patterns.
Therefore, no matter how much you copied, you could never replicate ninjutsu beyond your own capabilities. Copying more techniques wouldn't result in a significant boost in power.
Take Kakashi for instance, he was said to have over a thousand jutsu, but even if you added another thousand, it wouldn't dramatically increase his strength.
After all, a ninja's strength wasn't determined by the number of jutsu they knew.
That was why the Uchiha clan rarely relied on copying. They preferred to develop higher-level applications of the Sharingan. That was how true strength was gained.
Kaiseki, however, was different, it offered insight into the very essence of things. Of course, there was still a difference between analyzing and mastering.
It was like a person who completely understood the structure of a machine, just because you knew every component didn't mean building the machine was easy. It still took immense time and effort.
To unleash the full potential of Kaiseki, one had to possess unparalleled talent.
And coincidentally, Shin considered himself unmatched in talent in the current shinobi world. While Orochimaru was progressing, so was he, and with the help of this eye, his advancement was even faster.
As for the ability in his right eye, it bore a resemblance to Izanagi...