The Transmigrator - Uesugi Shinji

Uesugi Shinji remained unfazed by the killing intent locked onto him by Shirokumo Hayama. Although he appeared to be a young ninja of less than twenty years, in reality, he was the person on this battlefield who had experienced the most bloodshed!

No one would ever guess that he was a transmigrator, and that his soul had only arrived in this world a mere three years ago.

Before his transmigration, Uesugi Shinji had been a core member of a multinational mercenary group. For years, he had completed various commissions for high-paying employers, with assassinations, terrorist attacks, and the theft of classified intelligence all falling within his scope of work.

During his final operation, he was tasked with seizing a chip known as the "Light Brain" from a heavily guarded national research institute and destroying the cutting-edge equipment capable of manufacturing it.

Uesugi Shinji overcame countless obstacles and sacrificed a large number of his subordinates to complete the mission, only to be double-crossed by his employer during the delivery. In the end, he fought with his life on the line and took the ruthless employer down with him.

However, what he never expected was that after his death, his soul would transmigrate into the body of a Kirigakure chunin in this current world, and he would completely devour and inherit the memories of this unfortunate ninja.

After transmigrating, Uesugi Shinji discovered to his surprise that, along with him, the Light Brain had also crossed over. The Light Brain was a piece of technology that had already been converted into energy, and it had fused directly with his soul.

After a short period of exploration, Uesugi Shinji successfully mastered how to use the Light Brain.

The Light Brain had many uses, but for him, its most powerful capability lay in its immense analytical and computational power. Having fused with his soul, the Light Brain functioned just like a natural part of Uesugi Shinji's brain, seamlessly integrating with his existing cognition, experience, and knowledge to assist him in his analysis.

In terms of ninjutsu development, the Light Brain could determine the most concise hand seals and the most efficient sequencing.

In the study of sealing techniques, the Light Brain could design the most optimal sealing formulas.

In the practice of taijutsu, the Light Brain could also formulate the most effective training methods by constantly scanning and analyzing the host's physical state.

The Light Brain had even analyzed the mysteries of Kekkei Genkai, helping Uesugi Shinji transform from an ordinary ninja into one who possessed the Ice Release Kekkei Genkai!

Kekkei Genkai are divided into two types: the first is a Kekkei Genkai where elemental chakra is combined with a special bloodline, such as the Sharingan of the Uchiha clan or the Shikotsumyaku of the Kaguya clan.

Such Kekkei Genkai rely primarily on a unique bloodline; even if the Light Brain could analyze them, it had no way to help the host master their power, unless one were to transplant the genes of a Kekkei Genkai user through human experimentation, similar to the methods used by Danzo or Uchiha Madara.

The other type of Kekkei Genkai does not rely entirely on bloodlines, but rather on the recombination of different types of chakra, such as the combination of Wind and Water for Ice Release, Lightning and Earth for Dark Release, or Lightning and Water for Storm Release, and so on.

Although this type of Kekkei Genkai can theoretically be created through the combination of different chakra natures, the difficulty is actually immense, as the ratio of the chakra combination and the method of fusing them to perform ninjutsu have extremely stringent requirements.

In theory, as long as a ninja masters two or more chakra natures, they could perform such Kekkei Genkai ninjutsu, but in reality, almost no ninja can achieve this through their own efforts; most who possess these Kekkei Genkai rely on the genetic memory within their bloodlines.

Uesugi Shinji possessed both Wind and Water chakra natures, and through the Light Brain's analysis, he successfully discovered the theoretical method to combine them into the Ice Release Kekkei Genkai.

This theoretical method was almost impossible for an ordinary ninja to execute because it required an extremely high level of chakra control, necessitating a perfect ratio and balance between the two combined chakra natures.

However, this requirement was not at all harsh for Uesugi Shinji, who possessed the Light Brain.

The Light Brain could scan the state of the chakra Uesugi Shinji controlled in real-time, helping him maintain the balance of multiple chakra natures. Coupled with his own decent talent and diligent practice, he successfully turned theory into reality, completing the development of the Ice Release Kekkei Genkai through acquired effort!

Ice Release chakra was highly effective in offense, defense, and restricting enemies; mastering the Ice Release Kekkei Genkai represented a qualitative leap in combat power for Uesugi Shinji.

In the three years since his transmigration, Uesugi Shinji quickly stood out among the chunin of the village and was promoted to jonin alongside his two equally capable teammates, one of whom was his current partner, Kisame Hoshigaki.

Their squad was currently affiliated with the Kirigakure Assassination Squad, and their direct superior was Suikazan Fuguki, one of the Seven Ninja Swordsmen.

The Assassination Squad was specifically responsible for eliminating those whom the upper echelons of Kirigakure deemed a threat to the village's safety, and the target they were to kill this time was the very Kirigakure ninja who had been captured by Shirokumo Hayama's squad.

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