This quest is not available in game.
Bring the Gems of Cobrahn, Anacondra, Pythas and Serpentis to Nara Wildmane in Thunder Bluff.
The druids in the Wailing Caverns, the Druids of the Fang, are an aberration. They were part of an order of noble druids whose plan was to heal the Barrens, but now seek to remake that land to match their own, twisted dreams.
The Druids of the Fang have four leaders, and each possesses a dream gem. Even now their faces haunt me! Defeat the leaders and bring me their gems, and the Barrens may again know peace.
Go, <name>. You will find them lurking deep within the Wailing Caverns.