Uchiha Kai continued living his life as usual over the next stretch of time, and Uchiha Fugaku never approached him again.
Though Uchiha Itachi was occasionally asked to visit Kai, he rarely showed up. Kai, for his part, didn't wait around for him either—nor did he have the time or energy to teach anything to a child. Even if he did, what would he say? Think for yourself. Judge for yourself. Use your own eyes to see the truth of the world?
Kai simply didn't have the luxury. His days were now filled with near-constant training alongside Hatake Kakashi. He didn't even seek out Kenta Imai or Aya Hyuga anymore. With no missions assigned at the moment, he had no reason to interact with either of them.
His impression of the two had soured significantly, and he suspected the feeling was mutual. Their dynamic was like three magnets—forever repelling each other, never quite managing to connect.
Training with Kakashi, a true prodigy, brought Kai more insight than he could've anticipated. However, what left Kai genuinely stunned was Kakashi's rate of improvement—faster than expected, almost unnaturally so.
Perhaps it was Kai's influence that led Kakashi to pick up the sword again. Rather than drifting down the path we know from the original timeline, he'd begun experimenting based on Kai's advice. The result was something that surprised even him.
Kakashi had always been a capable swordsman. Though his skills had dulled somewhat after Sakumo's death, possibly due to emotional trauma, the muscle memory remained. It had only been a little over a month since his last serious use of a blade, but now that he'd picked it up again, it felt like a perfect fit—he was even stronger this time.
His Sharingan had accelerated his growth tremendously. While Kakashi didn't waste chakra on genjutsu or other unnecessary illusions, he was learning to use the Sharingan's predictive capabilities to the fullest.
He hadn't abandoned ninjutsu, either. In fact, he'd kept Kei's advice in mind. Kai had once proposed a refinement to Chidori, and they'd even discussed combining ninjutsu with swordsmanship. Kakashi had clearly taken those ideas to heart.
The result? During a recent spar, Kakashi unveiled a new technique that caught Kai completely off guard. His short sword shimmered with a pale blue glow, crackling with barely contained Lightning Release. The sudden burst of speed and precision—it was almost terrifying. If Kai's reaction hadn't been slightly faster, he might've been taken out instantly.
If that attack had landed on a real battlefield, Kai might not have survived.
What shocked him more was how efficient the technique was. It barely consumed chakra. Kakashi's reserves were still modest—typical of most Sharingan users not born into the Uchiha—but this new style didn't tax them heavily. He no longer looked like the version from the original timeline who'd collapse after a few fights… though Kai suspected Kakashi sometimes exaggerated his limits.
After the match, the two collapsed near a tree, panting from exertion.
"This is your new kenjutsu technique?" Kai asked, brushing dirt from his sleeves. "That burst of acceleration—Lightning Release stimulating your nervous system?"
"Yeah." Kakashi glanced at the sword in his hand, a mix of pride and disbelief in his expression. "I didn't expect it to work so well on the first try. Maybe it's Obito's blessing… or the fact that I created Chidori in the first place. Who knows?"
Obito's blessing? Kai scoffed inwardly. Obito isn't even dead yet.
But he didn't correct him. What mattered was the sword technique itself.
Kakashi didn't seem interested in keeping it a secret—perhaps because he saw it as a product of their combined efforts. After all, Kai possessed both the Sharingan and Chidori himself. It was only a matter of time before he discovered something similar.
Thanks to Kakashi's explanation, Kai grasped the essentials of the technique. Kakashi's short sword, once Sakumo's, shared the same high-chakra-conductivity metal as Kai's own blade. It allowed chakra infusion and ninjutsu amplification with remarkable efficiency.
To conserve chakra, Kakashi coated the blade with only a thin layer—just enough to increase sharpness and conductivity. But here was the twist: the moment an opportunity arose, he could unleash a concentrated burst of Lightning chakra. The chakra would supercharge his nervous system for a split-second, granting him incredible acceleration, while also transferring electrical current through the blade into the enemy.
Not only would this paralyze the target, but the internal damage caused by the Lightning chakra could be devastating.
Three traits defined the sword: burst, paralysis, and internal destruction. Unless the opponent was especially strong or heavily defended, a single hit could end the fight.
Kai thought of how Sasuke's Chidori had once left Yamato paralyzed on the ground. The lethality of Lightning chakra was no joke.
He stroked his chin thoughtfully. Kakashi's growth was on the right track, and more importantly, his development was proving useful to Kai's own path. Watching Kakashi refine and test these techniques gave Kai the opportunity to absorb the best of them—knowledge without risk.
It wasn't fair, but that's what made him a good mentor, right?
And to Kai's eye, the sword technique suited him, too.
It was a solid start. Kai believed Kakashi would develop more unique techniques in the future. When that time came, Kai would be right there beside him, quietly "harvesting" those ideas while keeping their friendship—or at least their alliance—intact.
"By the way," Kai said, reclining against the tree trunk. "Does your sword technique have a name?"
"I haven't really thought of one," Kakashi replied, scratching the back of his head. "But maybe you should name it. You're the one who inspired it, even if I developed it."
"Hmm… me?" Kai tilted his head thoughtfully. After a moment, he asked, "What do you think of Lanqie—'Lightning Sever'?"