Tempora Mutantur: Referee Supplement The Creep

In the years since the Fall, the myriad of mutant plagues, environmental poisons, and radionucleotides have mingled to the point where, with respect to their impact on living beings, they are all the same global ailment. To the folks who roam the wastes, the effects of all the toxic goops and lethal pathogens are thought of as a single plague: the Creep. (publisher blurb)