Black War Kodo
An epic mount. Part of the PvP honor system Rewards. Previously available to members of the Horde who have reached a minimum PVP rank of 
[Lieutenant General] (rank 11), now can be bought for 30 Marks Of Honor from Arathi Basin, Warsong Gulch and Alterac Valley.
Before patch 2.0 this mount only required Riding Skill 75 and level 40, after patch 2.0 it requires Riding skill 150 and level 60.
There are also three more choices of reward mounts for the Horde:
[Red Skeletal Warhorse]
Black War Wolf
Black War Raptor