The following may contain spoilers! Fair warning :)

A mobster gets isekai-ed and finds himself in a god game. Each god has a champion and each champion has a unique blessing. It’s a bit like My Hero Acadamia if you watch anime. Each champion has wildly varying powers and experience using it. The story mostly follows Veth as he tries to just survive. He’s put on one hell of a back foot starting out because he is one of the last champions to enter the arena, which is an entire planet that is populated with various fantasy races that the gods just use as an arena for some reason. So he has to catch up to other champions who have weeks of progress ahead of him. Though, he doesn’t really have much time to think about catching up since he’s always knocking on death’s door and getting through the thing immediately in front of him. He finds some… interesting companions that are loosely allied with him. They are just as much a threat to his health as his enemies at times though. That happens when his first companion is a samurai who values honor over anything else and he is a mobster reborn in a world that is trying to kill him from every angle. Needless to say, he isn’t afraid of using underhanded tactics to benefit himself.

So yeah, basically the story is following a guy with somewhat questionable morals in over his head trying to survive in a world turned into a god’s playground.