He was originally a man of the Warring States Era.

The Sword Saint had lived in this cave for over two hundred years. What sustained him beyond the limits of a normal human lifespan was precisely this unique breathing technique.

And the title "Sword Saint" did not refer to one specific individual—it was a title passed down through the generations of those in the Land of Iron who had cultivated swordsmanship to the highest level.

As for his own name, it had long been lost to the passage of time.

Now, all he knew was that he was the Third Sword Saint.

His purpose in life was to pass on his swordsmanship before the end of his natural life.

And the Land of Iron was the foundation upon which this legacy was built.

When you flipped through the Sword Manual, sure enough, the understandings of three different people regarding swordsmanship were recorded within…

At the same time, you realized that the reason Mifune sent you here was likely to find a successor for the Sword Saint.

...

〖Year Seven〗

You gradually settled your mindset, practicing the breathing technique until it became second nature, while executing the techniques from the Sword Manual one by one, focusing only on those you deemed useful.

Under the Sword Saint's guidance, you began fusing them into your own style—"Empty-Handed Swordsmanship."

Thanks to the breathing technique, the Sword Saint's mentorship, and your previous years of studying his techniques, your potential began to grow by leaps and bounds.

You observed yourself. The light within your body—representing your unlocked potential—shone brighter than ever.

If you fully unleashed your strength, you could now draw out 70% of your power!

...

〖Year Eight〗

With the continued help of the breathing technique and the Sword Saint's guidance, you unlocked as much as 80% of your potential. However, the further you progressed, the harder it became to unlock more...

In the Land of Iron, many samurai could unlock 50% of their potential. Reaching 60% would make one the top disciple of a dojo and a guest of honor among daimyō.

At 70%, one could establish their own dojo, recruit disciples, and create their own school of swordsmanship.

80%—that would qualify someone as a sword master, a rare figure seen only once across several cities.

Unlocking 90% potential meant becoming a sword grandmaster—there were only seven or eight in the capital, most of them elderly.

Mifune, who reached such a realm before the age of seventy, was a prodigy seen once in a century.

As for someone with talent on par with the Sword Saint… such a genius might not appear even once in three or four centuries.

Even so, reaching the level of the Sword Saint only meant one thing: an old man standing at death's door possessed the strength to kill a Kage-level ninja in one strike.

But that body would only allow for one such strike.

To shinobi, this path would seem obsolete, yet in the Sword Saint's eyes, chakra was ultimately a shortcut.

And shortcuts always came with a price. Only through painstaking training could the body and spirit truly belong to oneself!

...

〖Year Nine〗

You hit a bottleneck in your swordsmanship. Only by continuing the breathing technique could you continue unlocking more potential.

Once again, the Sword Saint began demonstrating his sword techniques.

But compared to a few years ago, his physical condition had worsened noticeably. He would often stop mid-swing, panting heavily.

Yet you noticed something else—his spirit had become sharper, like a drawn blade.

He stood quietly in place, as if waiting for something… some moment to arrive.

...

〖Year Ten〗

The outside world—just like the previous three Shinobi World Wars—was once again plunged into conflict due to imbalanced economic development and the Akatsuki's plan to gather the Tailed Beasts.

Still, the Land of Iron remained neutral. War never reached its borders.

And it had no way of affecting you and the Sword Saint, both already fully devoted to the path of the sword.

...

〖Year Eleven〗

The war outside escalated into a fever pitch. A haze of death and bloodlust filled the world, and vast quantities of drifting souls and chakra began seeping into your mountain cave.

At this moment, the Sword Saint stopped his training again. He quietly adjusted his breathing, seeming to push himself into peak condition.

Suddenly, in a single instant, his eyes flared with golden light.

The radiance within his body was so intense, you could see it with your naked eye—even without using special techniques or dōjutsu.

This level of brilliance—you had only seen it once before, on Might Guy when he used the Eight Gates.

It meant that the Sword Saint had already developed his physical potential beyond 100%.

But unlike the Eight Gates, this new strength didn't come from forcibly drawing out power with chakra, nor did it carry any harmful side effects.

Instead, it grew steadily.

101%… 105%...

Eventually, the Sword Saint stopped at 200%.

You felt time itself halt. For several seconds, everything froze. Then, the world roared back to life.

Natural energy, lost souls, and chakra from dead shinobi were sucked into the Sword Saint's withered body like a storm.

Suddenly—

The storm ceased. The Sword Saint coughed up blood, and his already frail body shriveled further, his presence plummeting.

You flicked your finger and used Yang Release to send life energy into him.

His nearly extinguished strength flared back, and after his breakthrough, his power far surpassed the Kage level.

But the Sword Saint said his soul had been damaged—he wouldn't live much longer. Still, having broken through the limits, he considered his wish fulfilled.

Then, he explained to you the world he saw after surpassing the limits of physical potential.

"Shackles."

What he saw after surpassing the limit… were countless invisible shackles binding his body.

Only by breaking them could one truly transcend the flesh.

He had tried to shatter those shackles with his sword intent, but ultimately failed when his remaining potential was exhausted.

...

〖Year Twelve〗

The Sword Saint's death hit you hard. The world he saw beyond the body's limits, filled with shackles—it weighed heavily on your heart.

You buried him deep in the cavern, alongside the two Sword Saints who had passed long before...

From this day forth, you are the Sword Saint of the Land of Iron.

You retrieved a broken sword from his remains, etched with mysterious runes. The material was incredibly hard—even your Death Scythe couldn't damage it.

According to the old Sword Saint, this broken blade was the source of the sword legacy and the breathing technique.

Yet, you were unable to wield the sword or unlock the so-called inheritance within.

...

〖Year Thirteen〗

You remained in the cave and mastered all the techniques left behind by the three Sword Saints recorded in the Sword Manual.

...

〖Year Fourteen〗

You noticed that continued use of the breathing technique made it increasingly compatible with your body.

The gap between your soul and your flesh was shrinking more and more.

...

〖Year Fifteen〗

You no longer cared about the outside world.

Now, only one thought remained in your heart—just like the old Sword Saint, you would break through the human limit and glimpse the shackles he spoke of.

...

〖Year Sixteen〗

You fully integrated the swordsmanship of all three Sword Saints with your own style.

At the same time, with the breathing technique's support, your spirit now stood equal to your physical form.

The light representing unlocked potential bloomed brightly.

You realized that your potential had now surpassed 90%, steadily approaching the realm once reached by the Sword Saint.

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