No Way! The Cannon Fodder Female Supporting Character Is Actually a Genius Big Shot - Chapter 30

After being betrayed and killed by his own brother, 17-year-old orphan Elias Black is given a second chance—by a mysterious, demonic entity. Reborn with the “Devil’s System,” he must now collect souls, gain abilities, and exact revenge on those who ruined him.But each power comes with a cost—and the devil never makes a deal without expecting something in return.As Elias grows stronger, unlocking deadly skills and forming uneasy alliances, he faces an even darker truth: his rebirth is part of a much bigger, bloodier plan.

Sky is not born of Shen Huan, millennium is like night.

This is a rebirth who wants to release himself, and has an interesting life story after getting a less serious system.

- Description from Uukanshu

Reborn into the world of Yugioh, it's natural if my goal is to become the best duelist!

In a world where summoners wield the power to call forth vampires, elves, angels, demons, and all humanoid creatures from across the realms, Nathan found himself unable to summon beings except from beasts. However, those beasts are not ordinary beasts. They are divine beings who once stood at the same level, if not higher, than the legendary creatures the world ever knew. Casting his gaze to the left, Nathan sees numerous summoners accompanied by the likes of demon kings, archangels, vampire progenitors, and other legendary beings. Turning to the right, a massive army of alien symbiotes is waiting to attack. There was no fear in his eyes, because standing on his left is a majestic wolf who managed to kill a god, the legendary eight-headed serpent coils on his right, above him is the bird who is glowing like the sun, and behind him is a dragon that once gnawed the roots of the world tree. “Let the war begin.”