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Who needs a  Mood Ring when you can buy a mood mount?

I love the changing colors! I have seen other players (parked in front of the entrance to the Shrine or Auction House, naturally) on this mount, and the detail of the features, animations, and vibrancy of colors is amazing. Blizzard artists really out-did themselves.

From Blizzard Entertainment:

Make an exotic and stylish statement whenever and wherever you fly with the Enchanted Fey Dragon mount. This mysterious and magical creature lives for excitement and has a zeal for adventure. True to its characteristic flair, the Enchanted Fey Dragon shifts its skin color on a whim, making big gatherings of these mystic beasts an awesome sight to behold. (Source) 

The Enchanted Fey Dragon can be purchased separately or as part of a charity bundle that includes  Alterac Brew-Pup. The charity part of the bundle ended on December 31, 2013.

In addition, you can pick up a pup—and still help out this great cause—as part of our first-ever charity bundle! Adopt the new Alterac Brew Pup pet and the new Enchanted Fey Dragon flying mount together, and you’ll save $5 on the pair—while still sending $5 to Make-A-Wish. [from now until December 31, 2013 at 11:59 p.m. PST] (Source)

Links to the Blizzard Store for the mount: US & EU.

Links to the Blizzard Store for the charity bundle: US & EU.

Now available on the Blizzard Store website as of November 21st, 2013.