Jin looked up from the Scroll of Seals, rubbing his stiff neck. The thought of improving the Basic Internal Energy Technique gave him a splitting headache.
At its core, the Basic Internal Energy Technique served as a foundation for chakra and wasn't difficult to learn. However, enhancing it was an entirely different story – the difficulty was absurdly high.
The complexity of the sealing technique itself didn't change much, but the requirements for a ninja's aptitude skyrocketed. Two conditions were necessary: Shape Transformation and Nature Transformation.
Shape Transformation wasn't a major hurdle, as most ninjutsu involved transforming chakra's shape. But Nature Transformation was a talent possessed only by a select few ninjas.
Jin felt fortunate to have this ability. Until he could decipher the reason behind it, he could only attribute it to innate talent.
Breathing Technique and Steel Cutter Flash were ninjutsu that Jin created based on Nature Transformation. Spirit Ball, on the other hand, was purely Shape Transformation. And the Six Paths of Celestial Thief technique was the result of his chakra research.
Returning to the development of the Internal Energy Technique, the primary goal was to form a semi-nature, semi-chakra state within the body. Directly converting chakra into an elemental nature would harm the ninja. Adding a semi-chakra component allowed for safe storage within the seal.
To enhance the technique, the first step was to determine the nature to which the chakra would be transformed. This was the reason Jin had hesitated in developing it.
While the chakra-enhanced Internal Energy Technique would become stronger after fixing a nature, it would also limit the ninja, weakening the power of jutsu from other elements proportionally. This would lead to a singular focus in a ninja's abilities.
Except for a few jutsu that didn't involve elemental natures, the impact on other techniques would be significant. Jin possessed a natural affinity for all five elements, and it would be a shame to waste such a gift.
Developing a multi-natured Internal Energy Technique was theoretically possible. However, among those who had learned Jin's developed techniques, only Tsunade possessed the knowledge to contribute to the research on the Basic Internal Energy Technique.
Tsunade had the deepest understanding of the technique and had even made modifications, though not to the extent of a complete transformation. She had, however, paved a path forward.
As for Orochimaru, that guy was just waiting for a finished product. He had a mountain of his own research projects and simply didn't have the time to delve into the development of the Basic Internal Energy Technique. It was quite frustrating.
Jin had hoped that Orochimaru would contribute some theoretical knowledge to his research on the Basic Internal Energy Technique. Sadly, that wasn't the case.
He had to rely on himself. This meant the development of the Basic Internal Energy Technique had to proceed slowly, step by step. There was no rushing it.
Consequently, until he could figure out a way to integrate multiple natures, he had to start with a single element. This was what troubled Jin.
However, the jutsu in the Scroll of Seals, and the developmental approach Tobirama Senju took in creating them, gave him some ideas.
Among the jutsu listed, there were relatively few using the five basic natures: Wind, Fire, Lightning, Earth, and Water. Instead, Yin and Yang Release dominated.
Yin Release represented mental energy and could be combined with chakra to achieve effects similar to manifestation. Yang Release represented physical energy and could enhance vitality, even bringing inanimate objects to life.
If he chose the path of taijutsu, Yang Release would naturally be his first choice. But he wanted to capitalize on his inherent talent, making Yin Release a suitable option.
The manifestation abilities of Yin Release could potentially be used to transform into other natures in the future.
He had considered Yin Release before, but the Yin Release jutsu he knew were mostly clan secrets with specific physical and bloodline requirements. This discouraged him from delving deeper into Yin Release.
The techniques in the Scroll of Seals, however, had no such requirements, relying solely on a person's talent and comprehension. This prompted Jin to reconsider Yin Release.
"Even with Yin Release, my combat strength will be affected to some extent."
Fixing a nature would temporarily weaken him.
"But the Sharingan is a Yin Release Kekkei Genkai, right?"
The Sharingan was likely the ultimate Yin Release Kekkei Genkai. Jin speculated that the so-called Sharingan's ocular power was a form of extremely potent Yin Release chakra.
If his theory was correct, while the power of many of his jutsu would decrease, his Sharingan abilities would be enhanced. This increase and decrease would maintain a balance in his overall strength.
However, this level of power wouldn't cause significant waves in the current ninja world.
"I can transform to Yin Release first and develop it further later, relying on the Sharingan to maintain my combat balance in the meantime."
With this thought in mind, he made a decision.
"Deduce: Yin Release Chakra Internal Energy Technique. Base it on enhancing the Sharingan, increasing its developmental potential, and adding the possibility of incorporating multiple natures."
He fed the necessary data into the Golden Finger. The text in the input box began to scroll rapidly. A flood of ninjutsu knowledge, theories, and development possibilities emerged, quickly forming an extremely complex sealing technique.
It was also divided into three levels, similar to the Basic Internal Energy Technique.
The good news was that it could be directly transformed from the Basic Internal Energy Technique. The bad news was that its difficulty was extremely high. Even with the assistance of the Golden Finger, it wouldn't be easy for Uchiha Jin to comprehend.
"Are there too many jutsu included in this?"
There was one thing that bothered him.
Jin rubbed his forehead. Despite the rapid scrolling of the text, he caught glimpses of some very unusual ninjutsu knowledge.
For example:
Izanagi, Izanami, Susanoo, Chibaku Tensei, Wood Release: Nativity of a World of Trees.
Had Uchiha Madara stolen his technique??
However, a this technique practiced by Uchiha Madara was a minor issue for now. Madara was still in hiding and wouldn't emerge until the Third Great Ninja War. He wouldn't truly step onto the stage until he regained his youth. Jin's Basic Internal Energy Technique didn't have the ability to reverse aging.
The key issue was:
Dust Release: Detachment of the Primitive World Technique! Lightning Release Chakra Mode!
What were these jutsu doing here?! Konoha didn't have these techniques! How could they appear after he hadn't checked for a while?
This implied that some hostile forces had obtained his jutsu.
Konoha was currently able to suppress three ninja villages with minimal losses, all thanks to the existence of the Basic Internal Energy Technique. But if other villages also obtained this technique, it would mean a comprehensive upgrade in the strength of the entire ninja world.
Konoha would be in trouble.
As the inventor, he wouldn't be directly implicated, as many people knew the Basic Internal Energy Technique. But if the inventor bore the Uchiha name, Hiruzen Sarutobi would definitely seize the opportunity to make a fuss.
Jin now felt like a giant target painted on his back. This blame wouldn't be easy to shake off.
But there was no need to worry. With his current strength, he could leave Konoha if necessary.
The most pressing problem was that it was already a struggle to develop a Yin Release Chakra Internal Energy Technique by combining the knowledge of the entire ninja world. How was he supposed to develop it further?
"Unless I get the entire ninja world to help me research the Chakra Internal Energy Technique."
If the entire ninja world were to explore this path, he could use the knowledge generated in everyone's minds to accelerate the development of his own Chakra Internal Energy Technique.