Adjusts the chance that any monster will respawn. Would provide a bit of unpredictability for Nightmare-esque difficulty settings. No effect when RespawnTime is set to 0. Default (0) would mean "always respawn."
I don't think you really understand how this works. The current probability is 4/255 per tick. There isn't much room to decrease likelihood, and increasing the value will make things unplayable.
