My Charity System made me too OP - Chapter 196: Battle Arena XII

Meet Sora and Shiro, a brother and sister who are loser shut-ins by normal standards. But these siblings don’t play by the rules of the “crappy game” that is average society. In the world of gaming, this genius pair reigns supreme, their invincible avatar so famous that it’s the stuff of urban legend. So when a young boy calling himself God summons the siblings to a fantastic alternate world where war is forbidden and all conflicts–even those involving national borders–are decided by the outcome of games, Sora and Shiro have pretty much hit the jackpot. But they soon learn that in this world, humanity, cornered and outnumbered by other species, survives within the confines of one city. Will Sora and Shiro, two failures at life, turn out to be the saviors of mankind? Let the games begin…

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

A High School Boy without friends, Odamori Tooru reincarnated into a Fantasy World after a bus accident on a School Field Trip. The job that was drawn 『Slavemancer』a Cheat occupation that dominates the minds of other.

The existence of a magician is to understand the truth of the real world. Saleen Metatrin, an ordinary magician, initially wanted to change one’s mind and destiny. During this, he went through many situations and phases in his life.