From WoWWiki

Fungal Giants are huge predators native to Zangarmarsh in Outland. Their prey are the native inhabitants of Zangarmarsh, including the Lost Ones. They are relatively peaceful creatures until they are provoked. They can also be "skinned" by those that have the herbalism skill.

Recently, they have come into conflict with Sporeggar. Driven by starvation due to the continuous sapping of the marsh's resource by the naga, they have began to roam the spawning glen, preying on sporeling young. Members of the Cenarion Expedition are looking for a peaceful solution to allow the two species to cohabitate the marsh.

If they are idle long enough, they will sniff their fungal-ridden armpits and then try to fan away the stink.

Fungal giants are considered giants in-game, showing the subclass "giant" under their names.

Notable Fungal Giants

•  Fhwoor, friend of the Sporeggar
•  Hungarfen, first boss of the Underbog
•  Quagmirran, final boss of the Slave Pens