You die pretty quick if you are not careful, then respawn a few moments later. You can be a monster and terrorize other player, be a prisoner
D-class/Guinea pig who has to escape despite all odds, a scientist who has to adapt to life and death situations, a guard that everyone is depending on, the rescue assault team that charges into the facility slaying every monster in their path while saving lives, or be the radicals who's goal is to free all D-class and exterminate all monsters and those who cultivates their safety.
You can also be a flamingo.