We must waste no time in dealing with the raven god. You must take the essence-infused moonstone to a place of great power in order to lure the god from the relative safety of the Emerald Dream.
Descend into the Sethekk Halls and set the moonstone in the clutches of the raven's claw. You'll find it in the chamber before the talon king's hall.
Anzu must be made to believe that his followers have gathered to welcome him back into the world. Once he has manifested, show him no mercy!
Progress
What news from Sethekk Halls? Have you defeated Anzu?
Completion
It's good to see you again, <name>. Your triumph over the raven god counts for far more than any test or rite of passage that I might set for you.
You have truly proven yourself worthy of the knowledge guarded by the Druids of the Talon for countless generations.
You must be honored with Lower City to enter Heroic Sethekk Halls. In the final room before the last boss in heroic Sethekk Halls is a claw which can be used to summon Anzu. Clear this room and place your stone. Once spawned, there will be three banished birds in a triangle around him. These birds can be brought to life with a HoT spell to gain a benefit of some sort for the duration of the HoT. This is easy enough to accomplish with one druid in tree form also healing the party, maintaining a lifebloom or a rejuvenation on each bird. Note that only Druid HoT spells will bring the birds to life; Renew simply does not work.
See the Anzu for a detailed strategy guide for defeating this boss.
Notes
Several druids in the group can complete this quest at the same time.