There are two PvP Talbuk mounts in Nagrand which are almost impossible to get because in order to get them you need 70/100 halaa battle tokens. To get a halaa battle token you need to get an honorable kill close to halaa. Which for a lvl 80 happens very rarely, unless you have a high enough lvl toon on the opposite faction which i do not.
For this to work you will need two accounts.
Create a dk and complete the starting zone quests, leveling it to 58. Then take it to Nagrand and sit it on one of the ledges surronding Halaa near the bridges. Then put your main on one of the floating islands or in halaa. On your dk run a "/who dalaran mage" and pick one of the mages. Send them a whisper saying something like "Hi, need a port to dalaran, my levels to low for this zone. Will pay 60g" and wait for their response. If they say yes just sit back and wait for em to get to halaa. When they get there and dismount come in on ur main and gank, helps if you bring a friend (You both get tokens). Make sure that when they are coming to you hide your main as they probably wont land if they see you.Usually you can get 1-5 tokens out of each mage, however, sometimes you get lucky and they call in reinforcements which means more tokens for you if u can beat them all (Friends really help here). This takes a while but if your going for the 50 or 100 mount achievements this is a faster and more reliable method than farming rare mounts.
Happy Farming