Few know of this place, and far fewer know of its location. This is a good thing, for nothing wholesome comes from here.
How long they carried him through those back tunnels, illuminated only by the flickering of torchlight, he had no idea. Then light seemed to explode when they reached the massive chamber. All around, unbelievably large red crystals captured the light of the flames and seemed to multiply it.
Pick up a pathology/microbiology book, and add the diseases/syndroms to your game. Your players will freak out.
Coughed at? Diphteria. or tuberculosis?
Drunk from a muddy stream? Or just walked through? Well, let us introduce you to schistosomiasis...
Hit by a stream of energy? Too moch mana is ust like too much radioactivity - perhaps all mages could develop cancer early if too powerful...