Chapter 15: Lightning Release Stimulation Method
"By the way, Kakashi—before you leave, how about a spar?"
Nan once again challenged Kakashi to a match. The two of them had already sparred a few times during their Lightning Release training, and the outcomes had always been fairly even—neither one able to dominate the other.
Nan's Fire Release was roughly on par with Kakashi's Lightning Release. Nan had the Sharingan, while Kakashi had speed.
Sounds familiar, doesn't it?
That's right—Kakashi's fighting style had a striking resemblance to Shisui's.
However, at this point in time, Kakashi was even more formidable than Shisui. He had far more combat experience, making fights with him significantly tougher than the ones Nan had with Shisui.
After reflecting on their previous duels, Nan realized something:
He usually won thanks to his greater stamina, but he lost due to his lack of speed.
He had to give Kakashi credit—no matter how the match unfolded, he could always force things into a dead-even draw.
Now, after his preliminary training in Lightning Release body enhancement techniques, Nan was finally able to use it—though not yet perfectly—to boost his speed for short bursts.
Having patched up his biggest weakness, he felt a surge of confidence. Beating Kakashi now? It should be easy.
Hearing Nan's challenge, Kakashi was a little intrigued.
During their first spar, he had thought victory would come easily. After all, Nan was only six years old.
When Kakashi was six, he had just become a Chūnin. Even if Nan was equally gifted, at most he'd only be Chūnin-level now—while Kakashi himself was already approaching Jōnin.
But the moment Nan revealed his three-tomoe Sharingan, Kakashi's confidence had wavered.
Kakashi knew all about the Sharingan—it was the Uchiha clan's Kekkei Genkai.
His own teammate, the idiotic Obito Uchiha, dreamed of awakening that eye.
And yet, at twelve years old, Obito hadn't even unlocked a single tomoe. Meanwhile, Nan—barely half that age—had already mastered the Sharingan to its three-tomoe form.
If Obito ever finds out… he might actually be so ashamed that he does something drastic, Kakashi thought, recalling Nan's teasing words.
Kakashi realized then that beating Nan wouldn't be easy.
Very few Uchiha reached three tomoe, and those who did were often elite Jōnin or high-ranking clan members.
Even if Nan couldn't fully unleash the eye's power due to his youth, the fact that he could use part of it was already a serious threat.
Sure enough, in battle, Kakashi discovered that Nan didn't just have the Sharingan—he also had double his chakra reserves, something he had already suspected.
But what surprised him even more was Nan's actual combat experience.
This wasn't the kind of textbook fighting you'd learn at the academy. Nan's moves came from real life-and-death struggles.
Where had a six-year-old learned that?
Kakashi's plan had been to use his speed to gain an advantage—but against the Sharingan, it wasn't nearly as effective as he'd hoped.
And once his chakra dipped and his performance started to drop, Nan would seize the moment with sharp, aggressive ninjutsu attacks.
The most frustrating part? At first, Nan only used Fire Release techniques.
But as the match dragged on, he actually started learning and copying Kakashi's Lightning Release jutsu using the Sharingan—and began using them against him.
The battle quickly turned into a game of attrition:
Would Kakashi's speed overwhelm Nan before his chakra ran out?
Or would Nan's superior stamina outlast Kakashi's bursts?
Eventually, both realized neither could decisively defeat the other, and they stopped sparring.
Kakashi, in particular, was reluctant to give Nan any more chances to copy his techniques.
It was just too much of a disadvantage.
Now, however, Nan had mastered the Lightning Release Stimulation Method—and he wanted to spar again.
Clearly, he believed this technique had compensated for his slower speed and was confident he could finally win.
Kakashi shot Nan a strange look.
Did he forget that I know that technique too?
Nan caught the meaning in Kakashi's eyes but wasn't concerned.
He felt he had a better grasp of the Lightning Stimulation Method than Kakashi did, and that's why he wanted a rematch.
After all, the technique had been co-developed by the two of them—but their training paths had diverged.
Nan used only a small amount of Lightning chakra to reduce strain on his body and extend his endurance.
Kakashi, on the other hand, had limited chakra to begin with, so he focused on explosive bursts, releasing large amounts of chakra all at once to achieve short-term speed spikes.
Who had the stronger version of the Lightning Release Stimulation Method?
Both Nan and Kakashi wanted to find out—so they faced off once more.
Nan, aware of his chakra advantage, activated the Lightning Stimulation Method right from the start.
Kakashi, however, couldn't afford to do the same. Due to his limited chakra reserves, his combat style had always been built around carefully probing his opponent with taijutsu first, then waiting for the right moment to strike with ninjutsu when the odds were in his favor.
His version of the Lightning Stimulation Method was extremely chakra-intensive, focusing on short bursts of overwhelming speed and power.
He needed the perfect opportunity to make it count.
In the first clash, Nan immediately gained the upper hand.
Aside from speed, he had never lagged behind Kakashi in any category—and now, with speed no longer an issue, he had surpassed him.
Combined with the Sharingan's predictive ability, Nan's speed was now significantly faster than Kakashi's.
And yet Kakashi still held his ground, thanks to that uncanny ability of his—to force a deadlock, no matter how bad the matchup looked.
But this wasn't luck. It was Kakashi's tactical brilliance in action.
He had a natural talent for playing to his strengths and minimizing his weaknesses, allowing him to maximize the effectiveness of his limited resources.
Though Nan had increased speed and power thanks to the Lightning Method, his close-quarters combat skills hadn't improved much.
Kakashi exploited this flaw to barely keep up with Nan's relentless offense.
But the longer the battle dragged on, the more Kakashi knew—he wouldn't be able to last.
Realizing he couldn't win in a prolonged fight, Kakashi began searching for an opening to launch a decisive surprise attack using his Lightning Release.
But Nan, with his highly perceptive Sharingan, was incredibly hard to fool.
Kakashi tried baiting him multiple times—deliberately exposing openings in hopes of drawing an attack, then counterattacking.
But Nan saw through every trap and avoided them all, rendering Kakashi's attempts useless.
That said, Nan wasn't in great shape either.
He desperately wanted to end the fight quickly, but Kakashi was proving annoyingly difficult to put down.
Without a technique powerful enough to secure a one-hit victory, the battle dragged on longer than Nan had hoped.
Nan was starting to feel anxious. After all, his Lightning Stimulation Method was still incomplete.
Prolonged use put heavy strain on his body.
To reduce the side effects, he was forced to gradually scale back the use of Lightning-style chakra transformations. This lowered the negative impact on his body—but it also made his acceleration less effective.
Kakashi noticed the drop in Nan's performance.
This was his chance.
Secretly forming hand seals, he unleashed a half-completed version of Chidori.
Crackling lightning burst from his hand and body, and in an instant, his speed surged explosively as he lunged at Nan.
Nan saw it coming with his Sharingan—
But while his eyes tracked the movement clearly, his body simply couldn't keep up.
Kakashi was just too fast in that moment.
Am I really going to lose here?
Nan wasn't ready to accept that.
Until now, he had only used the Copy Wheel Eye portion of his Sharingan in battles against Kakashi.
He had never once used the illusion-casting powers of the eye.
Now, with his body unable to react, he had only one option left:
Genjutsu.
In that critical instant, Nan used his Sharingan's illusion ability—for the first time ever on another person.
The only real counter to a Sharingan genjutsu is to avoid making eye contact with the user.
But Kakashi, fully focused on Nan, never expected a genjutsu attack at that moment.
He failed to react in time—and just like that, he was caught.
Kakashi's body froze in place. The lightning dancing along his hand and body fizzled out.
Nan vs. Kakashi: Nan wins.
After releasing the genjutsu, Nan looked over and saw Kakashi staring at him with a deep, brooding gaze.
Nan felt a little awkward.
He knew he'd basically cheated to win.
If he hadn't used genjutsu at the last second, he probably would've lost.
Kakashi, for his part, was quietly jealous.
As a ninja, he knew he was superior in overall skill and experience.
But unlike Nan, he was just an ordinary shinobi—he didn't possess a special Kekkei Genkai.
Recalling how easily Nan had copied his Lightning Release techniques with the Sharingan, Kakashi couldn't help but think:
If only I had a Sharingan too… I'd copy thousands of jutsus non-stop.