Some readers may have read it confusingly, so I'm going to talk about it here.

Humans: Tier 0 - Tier 10

Zombies: Tier Zero - Tier 10

Mutant Beast: Tier Zero - Tier 10

However, among the zombies and mutant beasts, the division of the four categories of ordinary elite boss kings has been added!

That's it in a nutshell, a bit like in an online game.