MTL - Dark Demon Warlock - Chapter 401 Ukageishi

Kuramoto Daisuke, a freshman in High School was suddenly exposed to someone vanishing in front of him. Turns out he was admitted to a Special Class full of Isekai Heroes that were regularly summoned to Otherworlds since the start of their Middle School. He was told that he was to become their Support to prevent each of the Heroes' fate of dying in the world they were summoned into. Though mediocre, he realized that his ability has a great potential but it needs a lot of hard work on his part.

Unconvinced of being just the Support Character, he vowed to excavate his mediocre ability, all the while supporting the Heroes using it.

And maybe more.

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

After the nuclear warfare, massacres started to spread throughout the entire world. The order between humans completely collapses, and the strong eats while the weak gets eaten becomes the #1 rule.

QiLeren had just cleared the bad ending of «The Nightmare Games» when his laptop died well before its time. His luck seemed to follow him as he was transported, along with the other passengers, to a hospital following an accident between his bus and a truck. Upon waking in a transfusion hall rather than a ward, QiLeren felt a familiar sense of dread as he took in the hospital that held no trace of other people…

Book 1 of a Trilogy

- Description from Novelupdates