As far as Azeroth goes, Ghost Mushrooms can be found only in Un'Goro Crater (in Fungal Rock). They grow exclusively underground. Each node yields only one Ghost Mushroom with a relatively high respawn time compared to other herbs.
In Outland, they have been spotted in caves in Zangarmarsh. The frequency of spawns seems to be dramatically higher in these caves than in Azeroth. A popular spot is the Funggor Cavern, in the south-eastern part of Zangarmarsh. Often up to three nodes are spotted at one time.
As an ingredient
This can be a very sought-after herb due to its scarcity and its use in invulnerability potions. Before Warlords of Draenor, it was the only way to make invisibility potions. It was also used by warlocks in their epic-mount quest (now obsolete), which required two Elixirs of Shadow Power. Since transmogrification was implemented, Ghost Dyes are in demand for some unique armor appearances. Since nodes are rare and out of the way and only give one each, supply is tight.
- Patch 6.0.2 (2014-10-14): Stacks to 200, up from 20.