The Celestial Unicorn is a Webkinz pet that you purchase at the Ganz eStore. It is not retired, and does not have a Lil' Kinz version. It can fly, and comes with a Treetop room. It is only available to Deluxe members.
Gallery
Celestial Unicorn Gift Box
Celestial Swing, the Celestial Unicorn's Pet Specific Item.
Soaring Star Sorbet, the Celestial Unicorn's Pet Specific Food.