The Phoenix flying mount is a very rare drop from Tempest Keep: The Eye. This is one of the most sought flying mounts in World of Warcraft: Burning Crusade, and hard to attain. Nazjatar realm only has two of these Phoenix mounts and incredibly in the same guild: Nascent. Check out the video and screenshots.
Special thanks to soundwave, and Onslaught from Nascent Guild (Horde), and to Alliance players: Amadeais from Death Dealers Guild for pointing me to Nascent. Vredesbyrd from Compilation guild for taking the time to port me to Shattrath City.