Reincarnated With The Undefeated System - Chapter 15 Learning What He Knows.

When a terminally ill young man awakens in the world of his favorite childhood game, he realizes he isn’t the protagonist, the destined hero, or even a major side character. Instead, he has become an extra—a disowned noble barely clinging to relevance in a world where strength determines everything. Worse, his fate in the game was to die an early, meaningless death.Armed with only his knowledge of the game’s storyline and a common system that tracks his stats and skills, he is determined to survive. But mere survival isn’t enough. He remembers a hidden easter egg from a long-forgotten anime collaboration: the Mangekyō Sharingan—a power limited by game mechanics but unrestricted in reality.With Kamui as his trump card, he walks the fine line between fate and freedom, seizing power from the shadows while avoiding suspicion. As the protagonist and his allies battle against demons and unravel the game’s grand destiny, he secretly builds his own strength—manipulating events, mastering forgotten arts, and even forging ties with villainous factions.Will he remain a footnote in history, or will he carve his own legend in a world that was never meant to be his?

『I’m terribly sorry…』

A god was suddenly prostrating in front of Kayano Takumi. He was apparently killed by mistake. Moreover, he can’t be reborn again. However, he is able to live in a different world? Then, let’s do that, please. The god made a mistake again and transferred me into a dangerous forest. Seriously, what’s going on? Besides, there are children here. I can’t leave them here, I will take care of them.

Under the vast immortal sky, the brilliance of an era is nothing but fireworks blooming at the fingertips.

Overlooking the earth, for thousands of years, life and death, where are they all? The Immortal Gate, the Dynasty, and the Supreme Holy Land are all just a handful of loess under the Immortal Vault.

A thousand years of splendor, and a smash into ashes.

Cinders sprout in the depths of the ruins, and you and I strive to be the trees that reach the sky.

What the hell is on the other side of the Immortal Firmament?

- Description from novelbuddy

After being sent to another world because of a god's mistake, Lin Fan obtained the ability to...tame?

“What? As long as I raise affection, I can tame anything? Even gods?”

“Could I even make a harem with this power?”