"Wrong…"
"Here too…"
"Wrong, wrong, wrong!"
In the eerie glow of Shinji's Eternal Mangekyo Sharingan, fleeting, dreamlike shadows flickered past, carrying invaluable insights.
The visions from these fate branches were all of his failed attempts.
The consequences of these failures varied—some resulted in mere muscle strains, while others caused his heart to stop, nearly killing him!
Countless failures piled up, testing his resolve, as if the idea of fully optimizing the Breathing Technique was an impossible dream.
Yet, the corners of his mouth remained upturned.
The importance of taijutsu in the shinobi world was undeniable.
Even though shinobi had mastered a vast array of ninjutsu and genjutsu, the pursuit of taijutsu never ceased.
Ordinary shinobi's taijutsu training often focused solely on the muscular level, while more advanced taijutsu secrets delved into exertion techniques and chakra manipulation.
The pinnacle of exertion techniques was the Senju Clan's Monster Strength.
The Monster Strength wasn't tied to bloodlines. In the current timeline, Yakumo, and in the original timeline, Sakura, both mastered it through study and training.
The essence of the Monster Strength lay in precise chakra control paired with advanced exertion techniques, unleashing tremendous force in a short burst!
The pinnacle of chakra application, on the other hand, was the Fourth Raikage's Lightning Release Chakra Mode.
This technique used lightning chakra to fully stimulate the body, placing it in a hyper-active peak state for a period.
Both the Monster Strength and the Lightning Release Chakra Mode, deemed taijutsu secrets, were born from the painstaking efforts of generations of geniuses and a touch of luck.
Even so, they had their flaws.
For instance, the Monster Strength required charging up due to its reliance on exertion techniques.
While a master could drastically reduce the charging time through experience and skill, the process could never be entirely skipped.
In his earlier spar with Yakumo, Shinji had predicted whether Yakumo was using Monster Strength by observing subtle muscle movements in her arms.
The Lightning Release Chakra Mode had even more glaring flaws.
The ability to train in it was a gift in itself. In all of Hidden Cloud Village, only the successive Raikages could withstand the intense stimulation of lightning chakra on their bodies!
Even these secrets, refined over generations, had their shortcomings, showing just how difficult it was to create an entirely new taijutsu secret.
Knowing this hardship only strengthened Shinji's resolve—countless failed visions didn't crush his confidence.
He had the complete texts of dozens of Breathing Techniques, painstakingly developed and perfected by Demon Slayer Corps swordsmen over centuries.
He had the insights and experiences of generations of genius swordsmen, meticulously collected by Ryūhei Ubuyashiki.
He had the support of the shinobi world's entire medical ninjutsu system.
And he had the dojutsu Izanami no Mikoto, which allowed him to peer into fate and experiment through trial and error.
At this moment, he stood not just on the shoulders of generations of geniuses but atop their heads!
What reason did he have to back down?
Six minutes passed, and the trial-and-error process continued!
Among hundreds or thousands of failed visions, only one or two showed success. Even those rare successes had issues requiring further refinement.
If Shinji's dojutsu power hadn't reached an extraordinary level, he couldn't have sustained such reckless use of his dojutsu. Had it been Sasuke with only a Mangekyo Sharingan, he wouldn't have lasted a minute before exhausting his dojutsu power.
After persisting for another three minutes, Shinji finally deactivated Izanami no Mikoto.
"Huff, huff…"
Breathing heavily, his face betrayed undeniable fatigue, but his now-normal Sharingan sparkled with excitement.
He cared not for the cost—only the results!
Of his condensed twelve forms, two were nearly perfected, and he had a clear direction for the remaining ten.
Moreover, through frequent use of Izanami no Mikoto to peer into fate, he had begun to grasp some techniques for fate manipulation.
In short: peering into fates that only affected himself, or temporarily only himself, resulted in relatively minor backlash. Conversely, the broader the scope of the fate he peered into, the harsher the backlash.
He even had a faint feeling that if he dared to peer into the fate of the entire shinobi world, he would invite some indescribable terror!
While recovering his dojutsu power, he returned to his study to summarize his findings.
Then, he immediately went back to the training arena to practice what he'd learned.
Boom.
With a low thud, a dummy made of ironwood was obliterated by Shinji's punch. This time, he only felt a slight surge of blood and numbness in his arm—no internal injuries or vomiting blood!
"It worked!"
Shinji grinned.
The surge of blood and arm numbness, to him, were merely signs that he hadn't yet achieved perfect bodily coordination.
If he could fully master all twelve forms of his optimized Breathing Technique and unify his organs, that punch might only cause slight numbness from the recoil.
Confident he was on the right path, Shinji rested briefly before activating Izanami no Mikoto again, peering into fate's branches once more.
With his prior experience, this round of trial and error was even more efficient. Though he sustained Izanami no Mikoto for less than ten minutes, he tested three forms, making significant progress.
Through repeated cycles, by his fifth activation of Izanami no Mikoto, Shinji not only completed the trial and error for all twelve forms but also fused them into a single cohesive whole, conducting his first overall test!
Success in individual forms didn't guarantee perfect balance when fused.
In fact, the failure rate for this holistic attempt was higher, and the consequences of failure were more severe—or more insidious.
From the failed visions in the fate branches, it was clear this round of testing was far more brutal. Scenes of his body exploding were common, and even in non-fatal failures, many hidden dangers lurked. Had Shinji not been a medical ninja, he might have overlooked these risks.