Naruto: Iron Fist Garp
Transmigrated into the turbulent world of shinobi, Ikki found himself thrust into the heart of the bloody Warring States period. He was no ordinary ninja; he had awakened a "system" that granted him the legacy of a legend—an enhanced version of the "Iron Fist," Monkey D. Garp.
Unlike the common shinobi whose prime withered with time, Ikki defied the laws of nature. Age was not a burden to him, but a catalyst; the older he grew, the more his monstrous strength intensified.
In an era defined by bloodlines and ocular jutsu, he had relied on nothing but his bare, iron-hard fists to beat both the Senju and Uchiha brothers into submission. His intervention brought the chaos of the Sengoku era to a definitive end, earning him the title of the world's greatest "Shinobi Hero" and the undisputed top rank among the Three Great Masters of the age.
However, as the era of warring clans transitioned into the age of Hidden Villages, Ikki chose to fade into the shadows. Disillusioned by the endless cycle of conflict between ninja and samurai, he retreated to the secluded back mountains of Konoha. There, he lived as a forgotten relic, an old man whose name had slipped from the pages of history into the realm of myth.
Peace, however, was a fragile thing.
The Third Shinobi World War erupted with a ferocity that threatened to consume everything. The "White Fang" of the Leaf had fallen to his own blade, and the legendary Sannin were pinned down on foreign fronts, leaving the village vulnerable and desperate.
With Konoha standing on the brink of ruin, the village leadership—the council of four led by the Third Hokage, Hiruzen Sarutobi—was forced to make a desperate pilgrimage. They went to the mountains to plead with a legend they had hoped never to disturb.
After decades of silence, the Hero of the Sengoku was coming out of retirement.