Luma

A Luma is a creature mentioned only in Super Mario Galaxy. They are star-shaped, flying organisms of multiple colours, which accompany Princess Rosalina in the Comet Observatory in the game. They possess the ability to transform into a variety of objects such as planets and Launch Stars, a fact that is used in-game by Mario as a means of progressing. It is often required that they be fed a number of Star Bits to be able to perform this feat.