Ashes of Al'ar
The Ashes of Al'ar mount is a very rare drop off of Kael'thas Sunstrider whom is the final boss of Tempest Keep. Since Tempest Keep is a difficult instance to do (still...) this mount will not be easy to get. You will still be required to organize a raid of at least 5 to 10 people before you will be able to take down Kael. The downside of that is the more people you bring with you the more competition you're going to have when the Ashes of Al'ar mount drops. Not only that but this mount has a 1 in 100 chance of dropping. Ouch.
If you think you're super badass and still want to try soloing this instance go ahead. But at level 85 I can guarantee you that this will be 110% impossible. I'm amazing at this game (as you can see my arrogance does not elude me) and I only managed to clear the trash. Also I did that when prot paladins were the most OP things since Warlocks in Classic or Death Knights in Wrath. Since their self healing got nerfed you mine as well fogett abouuut itt.
Maybe at level 90 if everyone has 200k+ HP this will be a little bit more feasible and you and a friend could plow through here but at the current point in time you're just not going to do it alone.
Good luck in trying to get the Ashes of Al'ar mount. You'll surely need it!
While running Tempest Keep hold onto all the greens you get and Disenchant them into Arcane Dust and Greater Planar Essences. Also keep all of the Netherweave Cloth that you come across as the Enchanting materials as well as Tailoring materials are always in demand on the Auction House and can net you a nice profit. Also all three of these items are part of my 10k an hour guide, which you can find more information on by following the links below.