Kill 6 Haldarr Satyr, 2 Haldarr Tricksters, 2 Haldarr Felsworn and then return to Loh'atu on the border of Ashenvale.
The satyr, a disfigured, evil aspect of the night elves, now infect the sacred lands once traveled by Cenarius. I cannot speak for the night elves when it comes to all the atrocities those demonic creatures have committed, but I have sworn an oath to the Earthmother to aid the elves in ridding the land of such a nuisance.
I am sure you would prove yourself if you aided me in purging them.
Northeast of here, you can find the Haldarr clan. Return to me after you've tested yourself against their power.