According to the lore, the Ixali revere Garuda as the Empress of Birds, a soaring deity who maintains an appetite for the flesh of land-dwelling creatures. She is the incarnate strength of the bird-men as well as a source of great terror. But just as with Ifrit, players who defeat her can expect to have a variety of fantastic weapons, as illustrated in the video just past the break. Just be careful -- if you aren't on the ball when you fight her, you could find yourself completely blown away.
[Thanks to Alex for the tip!]