Become the Obsidian Nightwing.
Blizzard has updated its World of Warcraft Recruit-a-Friend program to introduce the Obsidian Nightwing mount.
"Unlike most other mounts, the Obsidian Nightwing is not a mount you summon, but rather a mount that you become, enabling you to take to the skies with a friend riding on your back," explained Blizzard. "And who wouldn't want to ride (or transform into) a winged panther?"
The previous reward mount, the X-53 Touring rocket, has now been retired from the program.
All other aspects of the Recruit-a-Friend program remain unchanged, details of which you'll find on Battle.net.