A Five Room Dungeon about finding the Imperial city of The Lost Empire.
This is the tomb of an ancient knight, later made politician. He fought in countless battles, and his fabled armour is said to have been buried with him.
A traveling dungeon of canvas and props…
You find a patch of edible funghi. They taste well and all, no ill effects. UNLESS you consume some beverage, even 3 (three) days after eating it. Then you become really sick with pains, vomiting, all the fancy stuff. As a gift or good meal, it could be a cruel joke or to make sure the heroes spend their time focused on the mission. And the fine soup you had in the inn yesterday could have some in.
(Inspired through a real-world fungus. Was really used to cure alcoholism.)