Shimizu gained tremendous insight from his exchange with Tatewaki—especially Tatewaki's understanding of swordsmanship, which felt as though it had opened the door to an entirely new world.
Originally, Shimizu had planned to model his weapon after the White Fang's short blade and Sasuke's Kusanagi sword—creating a chakra weapon capable of transmitting Lightning Release chakra.
But after absorbing Tatewaki's philosophy, he began to feel that a Wind Release chakra weapon might be even more formidable.
Lightning chakra weapons looked flashy and came with a paralysis effect—but none of that compared to the sudden Wind Release sword strike Tatewaki had used in battle. If Shimizu hadn't possessed strong sensory abilities, escaping that subtle, nearly invisible pale-green slash would have been incredibly difficult. That faint cyan glow was so light it could easily be overlooked in a split second.
Indeed, Sasuke's Kusanagi sword looked stylish—but in real combat, Asuma's Wind Release chakra blades were probably far more practical. Subtle. Deadly. Powerful.
And according to Shimizu's combat philosophy: either unleash large-scale devastation—or fight like a cunning schemer from the shadows.
Looking cool?
The farther that idea could roll, the better.
Thus, Shimizu made up his mind. In the future, he would commission a master craftsman to forge a Wind-attribute chakra weapon.
Tatewaki had even introduced him to a renowned blade-making master from the Land of Artisans, someone Shimizu could visit when the opportunity arose. Previously, he only knew that the Land of Artisans specialized in crafting ninja tools supplied to all nations—but he had no idea whom to approach for a truly powerful and perfectly balanced chakra weapon.
Tatewaki's information was an enormous help.
The only issue—
He would now need to develop a fourth chakra nature: Wind Release.
For someone of limited innate talent, that pressure was immense.
After Tatewaki left, Shimizu immediately closed his eyes and carefully recalled the sensation from when he had activated that no-seal Chidori derivative.
His heart burned with excitement.
He desperately wanted to fully refine and master this new technique.
In twenty years, this was the first time he had truly created a ninjutsu entirely on his own.
How could he not be thrilled?
He had always been constrained by so-called geniuses—people who developed jutsu as if it were child's play. For Shimizu to learn a technique, he had to exhaust himself, sometimes even depending on others' moods and goodwill.
This success proved that his years of effort and study had not been in vain.
A person must affirm themselves. That, above all, is the greatest encouragement.
Though this breakthrough had come from a moment of accidental inspiration, Shimizu firmly believed it was the natural culmination of long accumulation.
He began circulating Lightning Release chakra again, slowly gathering it into his left hand.
Unlike Chidori, which required hand seals before activation, this time he simply followed the feeling—guiding chakra directly into his palm.
It worked.
Once again, the no-seal technique manifested.
Blue-white lightning crackled, accompanied by the sharp chirping of birds. Its intensity was not as overwhelming as Chidori, but its shape was no longer a fixed sphere.
Instead, it resembled a branching, tree-like bolt of lightning.
A strange form.
He needed to test its properties.
Body Flicker Technique!
Shimizu moved outdoors. He gathered chakra into his left hand again—this time much faster than before. With enough practice, he believed he could eventually cast it instantaneously.
A high-lethality, no-seal technique with surprise factor—perfect for ambushes.
However, due to its unstable, branching lightning form, he could not maintain it for long. After less than thirty seconds, the technique automatically dissipated.
Still, its unusual shape sparked an idea.
Perhaps he could throw it at range?
Unfortunately, the moment the lightning left his hand, it vanished instantly.
Unwilling to give up, he tried several more times.
The result was always the same.
This new technique could not perform long-range attacks.
It remained a close-combat Lightning Release ninjutsu—and its destructive power was noticeably weaker than Chidori.
The only consolation was its relatively low chakra consumption. Compared to Chidori, an S-rank technique with massive chakra drain, this one consumed roughly 1.5 times the chakra of a standard A-rank technique—far more manageable.
Still—
Its inability to strike from range greatly diminished its practical value.
If it already resembled branching lightning, why did it disperse upon leaving his hand?
Because it was unstable?
If stabilized, would long-range attack become possible?
Or—
What if it had a medium?
If he attached this unstable Lightning Release technique onto a chakra weapon and then threw it—
Would that make ranged attacks possible?
The moment the idea formed, Shimizu acted on it.
He immediately borrowed a Lightning Release chakra weapon from Tatewaki. Normally, such weapons were astronomically expensive and extremely rare. Fortunately, this was the Shogun's residence of the Land of Iron—home to countless top-tier weapons. With Tatewaki personally stepping in, one of these scarce and powerful blades was placed in Shimizu's hands in the shortest time possible.
Shimizu, however, showed no intention of treating this priceless weapon gently.
He activated his new technique at once.
Lightning flared, accompanied by the sharp chirping of birds—
Then he slowly guided the energy onto the chakra katana.
Instantly, the lightning and chirping ceased.
All that remained was a faint, glass-like blue glow enveloping the entire blade.
A flash of understanding struck him.
Without hesitation, he hurled the katana toward a large tree dozens of meters away.
Boom!
The tree fell instantly. Its trunk split cleanly in two, blown apart at the center.
Using the Body Flicker Technique, Shimizu appeared beside the fallen tree and picked up the undamaged katana.
"As expected of a fine blade," he praised.
This time, he directly infused the weapon again with his new technique. The same pale-blue glow wrapped around the katana's surface.
He threw it at the ground nearby.
Boom!
"So this is the correct way to use this technique… I can't believe I actually created a brand-new ninjutsu!"
The excitement in his heart was no different from when he first learned his very first technique. This milestone brought him one step closer to the summit he had always aimed for.
At this point, Shimizu had a clear concept of how to use the technique.
Next, he would definitely need to visit the Land of Artisans—not only to forge his future Wind Release chakra weapon, but also to commission as many Lightning Release chakra kunai as possible.
Only then could he properly test this new technique's range and destructive power—and fully integrate it into his combat system.
After all, a katana was not a projectile weapon. Further testing with it was of limited value. And if he caused any more commotion, that troublesome little princess might draw up yet another compensation contract.
As for the name…
He would call it:
Lightning Release: Thunder Blade Slash.
So far, it had two known applications.
Without Lightning Release chakra kunai, it functioned as a lightning-attribute dagger lasting about thirty seconds.
But when paired with chakra-conducting Lightning Release kunai—
It became a highly concealed rocket launcher.
Its chakra consumption was roughly 1.5 times that of a standard A-rank technique—about half the cost of Chidori by comparison. Yet its explosive power and area of effect were extremely impressive, no weaker than a paper bomb tag.
A highly practical new jutsu.
As long as he had enough Lightning Release chakra kunai—and sufficient chakra—this no-seal technique would allow him to unleash rapid, consecutive long-range explosive attacks like modern armored weaponry from his previous life.
Just thinking about it was enough to make him giddy.
An incredibly powerful A-rank technique.
This trip to the Land of Iron had been more than worth it.