Naruto: Lord Madara Was Right, but You're Not Ruthless Enough

[Single-player endless progression] + [Naruto] + [Multiple heroines] + [Decisive and ruthless] + [Infinite Tsukuyomi for all] + [Madara kneels]

He transmigrates to the beginning of the Third Shinobi World War and becomes Matsushima Terusora, Kakashi's classmate and the youngest son of a minor clan. Given a randomly assigned third-rate emotion-manipulation System, he decisively throws in his lot with Orochimaru.

He can return to Blue Star for one day each month, and he won't waste this perk. In the real world, he takes back all the good times he was denied for twenty years, throwing his weight around and behaving like a tyrant. But as soon as he returns to the Naruto world, he keeps his head down, living from one day to the next and racking his brains to use every trick he can think of just to survive.

A year later, Orochimaru nods at him. "Terusora, you've done well lately. I want to reward you. A Sharingan, or...?"

Matsushima answers timidly, "I want the forbidden jutsu: the Chimera Technique."