Stinkmold

This delightful hazard appears to be simple, innocuous mold on cavern or passage walls. However, when any warm-blooded creature approaches within 10 feet, the mold gives off a fetid cloud of unbelievably foul-smelling gas to a range of 60 feet. Creatures caught in the area of effect must make a Constitution check each round they are within the area. Failure means the creature is helplessly gagging and vomiting, losing d4 points of Constitution for d4+4 hours in addition to suffering -2 penalties to attack and damage rolls during this time. Three successive successful Constitution checks mean that the character gains temporary immunity to the stinkmold (essentially, his or her sense of smell shuts down for d3 hours). A 10' x 10' area of stinkmold can be burned away with a torch in a single round, but unfortunately burning stinkmold smells even worse than usual, requiring further Constitution checks (even among those who pass the previous checks) at a +2 penalty to the dice roll for the following turn. Note that a Control Temperature 10' Radius spell is a very effective way of bypassing stinkmold.