"Hey there, you look like a sturdy fellow! Interested in a treasure map? Only a few gold coins and this map to an ancient ruins secret room can be yours!"
A Basic Dungeon Crawl that starts with a map.
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...