The name "Lanche" immediately struck a chord with Kakashi. Though not a Water Release user himself, he wondered whether techniques like this—based on elemental fusion—could be gradually developed over time.
In the Hidden Cloud Village of the Land of Lightning, there's a known kekkei genkai that combines Lightning and Water chakra: Storm Release (Ranton). It creates laser-like beams of energy, showcasing the potential of elemental synergy.
To Kakashi, Uchiha Kai seemed to offer more than just a technique—he offered a blueprint, an idea. Kakashi accepted this silent gesture of camaraderie, deciding to give it a try. Combining what he excelled at—Lightning Release—with elements of Obito's combat style seemed like the most fitting tribute... or perhaps the most natural evolution of himself.
Kakashi, at this point in time, wasn't yet the broken man reflected in the anime's later flashbacks. Rin Nohara was still alive, and that changed everything. Her presence, along with the fact that Kai had once saved his life, allowed their bond to develop into a genuine and trusting relationship.
As for the name "Lanche"…
Uchiha Kai's talent for naming jutsu clearly didn't match his skill as a ninja. He shamelessly borrowed the name from a game he'd once played. Still, the technique's effect resembled that source material well enough to justify it.
After obtaining the sword technique, Kai took some time to practice it. To him, it wasn't especially difficult. The real challenge lay in identifying an enemy's weak point, instantly channeling Lightning chakra into his blade, and delivering a paralyzing strike—either lethal or non-lethal depending on the intent.
This demanded a high level of perception and precise bodily coordination, but as a Uchiha, Kai wasn't lacking in either. What he particularly appreciated was the paralysis effect of the technique. Increasingly, Kai had been facing opponents capable of reacting to or even dodging his finishing moves.
In the past, when this happened, Kai would have no choice but to wait patiently and hunt for another opening. But with Lanche, even if his first strike didn't land cleanly, the resulting paralysis would likely prevent the enemy from evading a follow-up.
"But then again," Kai mused, "someone like Madara Uchiha... or even the Third Tsuchikage or Orochimaru... probably wouldn't be fazed by something like that."
He couldn't help but chuckle to himself. Madara's practically untouchable. Orochimaru just comes back to life anyway. This ninja world seemed peaceful on the surface—but it's a world of gods waiting to clash.
Kai once sighed at how the strength of modern shinobi paled in comparison to the legends. The First Hokage, the Uchiha of old—how did we end up with today's lot?
But after witnessing the next generation—Naruto Uzumaki, Sasuke, and others—he stopped saying such things out loud. He didn't even bother reading Boruto's records; that world looked like a true battlefield of deities.
Still, Kai thought, ninja are unpredictable. No matter their strength, each one can shine in their own way. But those born with kekkei genkai will always have an edge.
"Well, I'm one of those lucky few. I understand more than most. I have more options."
After parting ways with Kakashi, Kai began walking toward the Uchiha district. He had a clan meeting to attend, though there was still plenty of time before dusk.
As he walked, his thoughts drifted to his Mangekyō Sharingan. I already have the Mangekyō... but what comes next? Eternal Mangekyō? Without a brother, is that even possible for me?
He thought about his use of his dojutsu. Though he had only used his three unique Mangekyō abilities a handful of times, he had documented each one carefully. While each technique had considerable power, Kai knew they weren't yet in their "complete" state.
Is mastery simply a matter of chakra and practice? But won't that destroy my eyes over time...?
He refused to accept that fate. As for Susanoo, he had yet to fully unlock it—but he was beginning to see the path. Kai recalled that even Shisui and Madara had accessed Susanoo without a complete Mangekyō. Madara had gone so far as to summon it without any eyes at all.
This made Kai question whether Susanoo necessarily caused vision loss. Maybe, with the right control and understanding, its toll on the eyes is minimal or avoidable altogether.
He knew that Susanoo was a massive chakra construct—a warrior of defense and destruction. Its core, he theorized, was a fusion of Yin Release and the user's chakra. He didn't fully grasp how to extract Yin chakra, but having a direction was enough.
Beyond Susanoo, Kai had been analyzing the activation duration and chakra drain of his dojutsu techniques.
His first use of Stay of Time had been after a drawn-out battle, when his chakra and mental condition weren't at their peak. He had barely extended its duration by a few seconds. He was cautious—activating the ability against a powerful foe might burn out his eyes, and against a weak one, it was pointless.
The same logic applied to Leap of Time and Retrospect of Time. These two were less chakra-intensive, especially because they were monocular techniques. Kai remembered that Retrospect of Time had affected both Loess and the Iwa-nin named Akai, implying it could affect multiple targets within a radius.
Leap of Time was more suited for personal enhancement, allowing him to move with incredible speed and precision—enough to singlehandedly wipe out an elite Iwa squad during one operation.
"These techniques are closely tied to my chakra reserves and ocular stamina," Kai reasoned. "If I can expand both, maybe I can unlock their full potential."
He didn't know what the "complete" versions looked like, but one thing was certain: he didn't want to end each battle with aching, bleeding eyes.
What he wanted—what he needed—was control. With enough chakra and visual prowess, not only could he fully wield his three abilities... but perhaps summon Susanoo as well.
The power of the Mangekyō Sharingan required repetition, mastery, and research. No one had ever drawn out its full potential overnight. Even Obito relied on Hashirama cells and Zetsu's body, and Sasuke had learned through hardship and near-death.
Kai clenched his fists slightly as he walked, his thoughts clear: If I want to shape the future of the Uchiha, and survive the war to come—I have to go further than any of them.