"You bastard, what's with that look on your face?! To be appreciated by Lord Vegapunk... you should accept it with gratitude and prostrate yourself before him!"
Kakashi Hatake's long-faced expression was obvious. Before Vegapunk could even speak, Hancock, who was standing nearby, was already the first to show her dissatisfaction.
Seeing Hancock's fist turn black, cold sweat poured down Kakashi's forehead. He quickly tried to explain himself, "I'm just afraid my abilities are insufficient and that I'll delay Dr. Vegapunk's data collection!"
Kakashi was well aware of just how much power was contained in Hancock's seemingly fair and delicate arms! Even without using any Chakra, it was a terrifying strength comparable to or even exceeding the level of the Monstrous Strength Technique. If she were to give him even a light punch, half the bones in his body would likely break!
If this inhumanly beautiful woman didn't hold back her strength, it wasn't impossible that he'd end up scattered everywhere—or become Kakashi-chan.
"Then go ahead and practice it here first!" Vegapunk waved his hand and said directly, "The equipment here is the most advanced, so I can see the results of your training immediately!"
Kakashi Hatake's expression soured slightly, but he didn't say anything more. He had some confidence in his Chakra control. Moreover, Vegapunk was indeed an extraordinary genius; even if a newly created Ninjutsu was incomplete, it was unlikely to be something immediately fatal.
At worst, he'd just get injured! It was much better than becoming Kakashi-chan.
Opening the scroll in his hand, Kakashi's eyes narrowed slightly, and his expression gradually became serious.
At first, Kakashi thought it was a more advanced version of the Lightning Release: Cell Activation Technique, but after looking closer, he realized that the development direction of this Lightning Release was completely different from the standard Cell Activation Technique.
Rather than being a buff-stacking Ninjutsu like the Cell Activation Technique, it was more like a training method that used the power of lightning to strengthen one's physical body, similar to a Chakra Cultivation Technique!
In fact, high-level Lightning Release: Cell Activation Techniques inherently strengthen the body; otherwise, the successive Raikage wouldn't have all been such muscular powerhouses.
However, that was just a passive effect of the Cell Activation Technique. No one had ever thought of actively using that power to strengthen their physical body.
After all, permanently strengthening the body is much more difficult than stacking buffs, and the human body in the Naruto World has its limits.
Although it far exceeds that of humans in ordinary worlds, even when trained to the limit, it only reaches a certain level—at most, slightly more strength and speed. Flesh and blood still cannot match the strength of steel.
Figures like Might Guy and the Raikage can unleash such powerful destructive force with their bodies because they still rely on Chakra power; the physical body is, at most, a container to hold that Chakra.
Therefore, the cost-effectiveness of body strengthening isn't very high, and the danger and difficulty are much greater than simply stacking buffs.
However, the Ninjutsu Vegapunk invented was primarily designed with himself and Hancock in mind. The ceiling for pure physical fitness for humans in the One Piece World is much higher than for those in the Ninja World. Those monsters who train their bodies to the extreme can treat an S-rank Ninjutsu like a gentle breeze, so the benefits of physical training are naturally much greater for them.
After pondering for a while, Kakashi gained a bit of confidence in the Ninjutsu Vegapunk had developed. After all, with his knowledge, he couldn't find any flaws in Vegapunk's technique.
Furthermore, the training method was gradual. It didn't start with strong electrical currents right away; instead, it used Lightning Release Chakra to progressively stimulate and strengthen the body.
In other words, even if something went wrong at the beginning, it would at most cause some numbness; the possibility of injury was low, let alone anything fatal.
Seeing Kakashi sit cross-legged in resignation, Vegapunk smiled and placed several instruments on him, beginning to monitor the Lightning Release Chakra currents in his body... More than ten days passed quickly. During this time, there was never a shortage of test subjects in Vegapunk's laboratory. With the help of his quantum brain, Vegapunk gained a significant amount of Ninjutsu knowledge from these subjects.
Most Five Elements Ninjutsu weren't very useful to Vegapunk and the others. Vegapunk could only use pure Lightning Release. Besides the Ice Release Bloodline Limit, Hancock and Nico Robin could also use the Wind Release and Water Release techniques that merged into Ice Release, but the three of them didn't care much for these conventional Ninjutsu.
A bit of practice to get familiar with some offensive methods was enough. After all, conventional Five Elements Ninjutsu all had similar effects—they were nothing more than energy and matter converted from Chakra and molded into various shapes.
But through these Ninjutsu, Vegapunk could better reverse-engineer the nature of Chakra and develop techniques more suited to them.
On a training ground in the research institute, Nico Robin was currently practicing the Ninjutsu Vegapunk had developed for her. Her opponent across from her was the miserable Kakashi.
During this time, Kakashi not only had to practice the rudimentary Ninjutsu Vegapunk had created and help Vegapunk with chores, but he was also used as a training target for Nico Robin.
Fortunately, Nico Robin didn't use her Devil Fruit abilities or her Two-Color Haki during combat, relying entirely on her physical fitness and Chakra abilities to fight Kakashi. Otherwise, the current young Kakashi would be no match for an enhanced Nico Robin.
After not seeing him for half a month, Kakashi's height on the training ground had suddenly shot up by four or five centimeters. His originally thin body had begun to develop streamlined muscles, making him look much sturdier.
Clearly, the Lightning Release Stimulation Training Method was quite effective for Kakashi. Although it was hard to tell exactly how much his strength had increased, the improvement in his physical fitness at least meant his Chakra reserves were no longer so pathetic.
At his current age, the time Kakashi could use his Sharingan was originally measured in seconds. Unless he was using his ultimate move, Chidori, he wouldn't reveal his Sharingan at all, because the eye put far too much pressure on the young Kakashi.
Carrying such a burden during his peak physical growth period was the reason Kakashi's future growth fell short of expectations, causing him to fade into mediocrity. However, practicing this Lightning Release Body Refining Technique clearly compensated for many of his shortcomings.
At least now, Kakashi on the training ground could keep his Sharingan active during regular combat.