"With these hand seals, you can activate the Iron Skin Jutsu. It will be weak at first, but if you add these two seals and mold your chakra…" Saburo began explaining, performing each hand seal and the chakra molding process in detail.
At this point, the use of the Sharingan came into play. For Kaida, the flow of chakra inside Saburo's body was as clear as water flowing in a river.
With each hand sign, he could see how the chakra was reacting—when Saburo was adding more than just making hand signs, at what point he converted normal chakra into Earth chakra, and how he distributed it across his body.
'Boy, I may have been overestimating Kakashi a little too much. If learning a jutsu is this easy with the Sharingan, then maybe copying 1,000 jutsu—though exceptional—was not as great as I had thought,' Kaida mused when—
"That's it. Was there anything you didn't understand?" Saburo asked.
"No, sir, I understood everything," Kaida replied.
"Good. Then perform this jutsu now," Saburo said. He didn't allow any training time, as the person in front of him was an Uchiha with a three-tomoe Sharingan. Even without extraordinary talent, copying a jutsu that matches your elemental affinity is not something an Uchiha would struggle with.
Kaida nodded at the command and started making one hand sign after another, molding chakra and converting it into Earth chakra.
"Earth Release: Iron Skin Jutsu!"
On his first try, he successfully performed the jutsu. However, one thing was clear: the color of Kaida's skin was much lighter than the weaker version Saburo had shown. While Kaida felt disappointed, Saburo—who had also activated his Sharingan—seemed quite pleased.
"Good, very good. It was almost perfect. No wonder you won that Chunin exam. Your talent is nothing to scoff at. Now, you just need to modify this acupoint flow rate and…" Saburo praised Kaida before correcting the minor mistakes he had made while using the jutsu.
Performing the jutsu after seeing it once and controlling the flow efficiently was a testament to Kaida's talent—or rather, his enhanced chakra control and memory. Although the Sharingan was a major factor, his training in Medical Jutsu and other chakra control exercises also played a significant role.
Combining all these factors, Kaida cursed himself even more for not learning such jutsu earlier. He forgot how busy he had been, learning Medical Jutsu and Fuinjutsu simultaneously, mastering the Sharingan, training in Genjutsu, dealing with Danzo, befriending Kakashi, and bringing Naruto into his family.
Being a transmigrator had profoundly affected his thinking. Knowing that, in the future, even S-rank ninja like Kakuzu and Hidan would die like Genin—let alone normal elite Jonin—the level of strength he had achieved so far, which was a dream for thousands of ninja, didn't even feel like the starting point to Kaida.
Having already made changes far beyond anything reversible, the future would change completely. Fate could no longer be relied upon, and Kaida knew he needed strength to handle those changes.
With such thoughts, he absorbed everything Saburo was teaching, improving with each attempt.
After an hour of constant practice and repetition of the jutsu, Saburo said, "Good job. With this, you should be able to handle some C-rank jutsu with no damage at all." Saburo noted the tone of Kaida's skin, now identical to the weaker version he had shown earlier.
"Sensei, what should I do to make it as perfect as your version?" Kaida asked. Though he needed more time to familiarize himself with the jutsu, the base form was almost flawless. If he took his time while using it, there would be little room for improvement. However, Saburo's version was clearly beyond the norm.
"It's not rocket science, Kaida. I just supercharged my jutsu and used Yang chakra. It's a higher version of the same jutsu you're using. Supercharging this jutsu is easy, and once done correctly, it can block B-rank jutsu as well. But anything beyond that is impossible.
"That's why I use Yang chakra in conjunction with Earth chakra while performing this jutsu, making my version much tougher than normal."
'Supercharging the jutsu and Yang chakra, huh,' Kaida thought. But that was it; he didn't ask Saburo to teach him that. The reason was simple—it would be like asking a stranger to hand over their source of income. As a Taijutsu user, Saburo had perfected this jutsu. It would feel shameful to ask for it for free.
"Thank you for teaching me all this, sensei," Kaida said, bowing slightly.
Saburo smiled. Most young ninja would demand he teach them his version of the Iron Skin Jutsu as if he owed it to them. His typical response was a kick to their butts. But seeing the sensible boy in front of him, he smiled and said, "Master this jutsu and learn to supercharge it as fast as you can. Once you manage that, come to me again, and I'll help you upgrade it further."
"Thank you very much, sensei," Kaida said, bowing further before taking his leave. Saburo also gave him permission to use the machines in his yard whenever he had free time.
With one jutsu under his belt, Kaida moved to the next house. Learning a jutsu in just an hour had given him enough confidence to believe he could master the next two today as well.
The next person he visited was a Chunin. Kaida arrived at his house, only to find a young man, around 20 or 21 years old, sleeping.
"Oh yeah, I signed up for that. Yawn. Just give me 10 minutes," the man said, heading inside to wash his face.
…
"So you want to learn the Rotating Shuriken Jutsu? Do you know any Wind Style jutsu?" the ninja asked, standing with Kaida in the training area, as this jutsu required more space to practice.
"Yes, sir. I know the Wind Blade Jutsu and the Wind Instantaneous Movement Jutsu."
"Show me," the ninja said, activating his two-tomoe Sharingan.
Kaida nodded and performed both jutsu one by one.
"You have nice control over both of them. This shouldn't be too difficult for you," the ninja said, making hand signs with one hand while holding a shuriken in the other.
Swish.
With a flick, the shuriken flew toward a nearby tree but suddenly changed trajectory, evading all the trees in its path. It then made a 180-degree turn, returning to the ninja's hand.
"This jutsu works well during ambushes or for creating openings. My current best is controlling five shuriken at a time, but my sensei can do ten. It depends on how many you can manage simultaneously," the ninja explained.
Kaida nodded, activating his Sharingan in the middle of the demonstration. Observing the chakra molding process, he realized it was not overly complicated but quite intricate. The required chakra control was comparable to Medical Jutsu and Genjutsu, but thankfully, Kaida didn't lack in that area.
"Let's start with one shuriken for now," the ninja instructed, teaching step by step. Despite his young age, he turned out to be an excellent teacher.
In just two hours, Kaida managed to control three shuriken simultaneously.
"You're quite a monster! It took me months to reach this stage, and here you are, doing it in just two hours. Man, I wish I had a three-tomoe Sharingan," the ninja remarked.
"Thank you for the compliment, sir," Kaida said, bowing slightly. With two jutsu mastered, only one remained.