Rotten Mushroom is an Item in Diablo 3: The Darkening of Tristram
Description[edit]
A corrupt stench lingers around this mushroom, as though it is more than mere rot. Mixing it in a cauldron will yield a special brew.
Acquisition[edit]
Found in random position on Labyrinth Level 9 in the Anniversary Dungeon in the Black Mushroom.
This is part of the Rotten Mushroom Quest