Lychanids

The Lychanids are a collective of Fungal organisms which threatened to destroy the Fae, Elves, and Humans during the Hive Wars.  According to Elvish Mythology the Lychanids were brought to the Middle Realm by the Elvish mythological figure Ithidor who traveled between worlds and received a series of magical items from the Realm Lords, one of which was a box of mushroom spores from the Forest Realm.  These spores grew the first Lychanid Jungles, a vast magic jungle in which the Lychanids live.

Lychanids exist in different forms, their main hives are great networks of mycelium beneath the forest acting as collective minds, they can then spawn free roaming organisms which can attack and travel, spreading the colony spore and starting new hives. 

The Lychanids attacked the Elves and Fae, threatening to overwhelm both as the Lychanid Jungle spread further and further, finally, in what became known as the Hive Wars, the Fae and Elves pushed the Lychanids back behind a vast mountain range, containing them in the land that became known as Hivemoore.