Reins of the Raven Lord
The Raven Lord Mount is a rare drop from Anzu in Heroic: Sethekk Halls. Anzu used to only be able to be spawned by a Druid that has completed or was on his or her epic flight form quest but now he is a core part of Heroic Sethekk Halls. Regardless of if you have a Druid to spawn him or not Anzu will be there. As you can imagine the mount has an extremely low drop rate, roughly a 1% chance to drop. Despite it's low drop rate at level 85 this mount is pretty damn easy to farm. I can complete the instance in roughly 7-15 minutes depending on what class I am on and how much trash I want to clear.
In addition for a chance at the cool mount Anzu drops (the mount looks exactly like him) if you kill all the trash leading up to him and loot everything you can usually make 100 - 200g a run! Vendor all the greys, and blues that you get from the mobs and bosses and DE all the greens into Arcane Dust and Greater Planar Essences. Also sell all of the Netherweave that you get on the Auction House.