“ 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...”
“ The creatures in this dungeon will not become hostile so long as you do not cause any trouble inside. If you provoke them though, you aggro the whole dungeon. If the players are smart, they can complete the dungeon crawl without having to fight anything.”
“ As they travel they notice a horrible rotten smell. As they travel it gets stronger and stronger forcing them to cover their noses and mouth less they choke on the horrible smell.A small goblin tribe preparing a wedding feast. The wedding is between two tribes as a gesture for peace, if the PC's intefere, feirce fighting could break out.”