Tanbrosh
From Greyhawk Wiki
Tanbrosh is a flowering plant that can be turned into a potent narcotic. It grows near the village of Rastor in the Kron Hills.
It grants strength and endurance at the cost of wisdom. It is highly addictive, and addicts that attempt to go "cold turkey" without the aid of antitoxins or magic typically die without their fix within three days.
Bibliography
- Cook, Monte. Return to the Temple of Elemental Evil. Renton, WA: Wizards of the Coast, 2001.