Arifureta Shokugyou de Sekai Saikyou (WN) - Chapter 467

What happens when a fanfic author with a habit of lying and scheming suddenly finds himself as a self insert during Duelist Kingdom? What happens when you have Yugi, Joey, Kaiba, and the rest encounter someone who knows all about every major player in their saga... and sees no problem with abusing said knowledge? Chaos, dear reader. Sweet, sweet chaos

A top hacker was chosen by the Lord God to be reborn into countless worlds, always as an expendable villain.

With no free will, every world became a dead end. Every one of his lives ended tragically.

Finally, after wresting control of the Villain System, this ace hacker decided to enact revenge. Even if his very bones were rotten, he’d choose to occupy the very heights of morality, if only on the surface.

Thus, he would change his fate as an abused slag.

- Description from novelupdates

Vahn was an atypical youth. Due to a rare mutation, his blood had the potential to target and attack ailments within the human body. Touted as a universal cure, people had elevated his status above the norm and given him the classification "Panacea". In the media, he was hailed as a great hero who would usher in a new era or human wellness. However, behind the scenes things weren't so bright. Being a unique individual, Vahn spent his entire youth locked up in a lab with various scientists and research teams using his body and blood to perform endless amounts of experiments. The only solace in his suffering was the various anime and manga made available to him between experiments. He often imagined himself as the protagonist in a world of his own, finally in control of his own destiny. For years he nurtured this desire, until at the age of 14 he died when an organization had tried to kidnap him from the lab...

[Free New Book] The predecessor of the Immortal God reincarnate and reborn in the third year of high school. Based on the many exercises in the memory of previous life, he practiced again from scratch. There are many traces and treasures left by his previous life. To explore, he has to re-enter the peak of the earth!

- Description from Uukanshu