Caves of Deep Night
From WoWWiki
The Caves of Deep Night is reputed to be the location of a special fungus. The mushroom is said to grow only in the caverns. A few night elves believe that if this mushroom was brewed into a potion and fed to high elves via Theramore's water supply, that the high elves would overcome their arcane addiction.[1]
The Caves of Deep Night do not appear in World of Warcraft, and its location is unknown, though presumably in the Dustwallow Marsh.
