Ousama Game

A mysterious command arrives from a "King". The life-threatening "Game" has now begun for the 32 students of the first year's B Class. One day, all of the students in Nobuaki's class received their first message from someone calling themselves the "King", in which was written a baffling command. That first command was very easy. However, the commands began to escalate until a life-threatening game had begun. Failing to obey the orders leads to death!! Their friendships are being undermined by a bottomless terror!! (https://www.animenewsnetwork.com/encyclopedia/anime.php?id=19973) Official English translation on Comico's (https://www.comico.io/pocket-comics) (colored webcomic version)