RPG I: The Necromancer's Revenge

I teleport mushrooms into the food of elves, especially druids, so that if they go mad, there will be no one to heal the elves...

A Dryad approaches the food, in the name of Silanna! Why am I so hungry! She takes a dish and eats all the mushrooms and flies off to do her business. Apparently, they only have a positive effect on elves, as they grow them and have adapted to them, while they have an unpredictable effect on other races.