Ciela

Ciela, the Fairy of Courage, is the fairy that helps Link in Phantom Hourglass. She begins the game as a white fairy. By collecting 10 green orbs and offering them at Fairy Island, Ciela can allow Link to shoot lasers from his sword. Collecting 20 orbs doubles the width of the laser.

After beating the Temple of Courage, however, instead of a yellow fairy, another white fairy appears. Link goes to Oshus, who uses his staff to fuse the two together, revealing that Ciela is the Fairy of Courage. Prior to the game beginning, Ciela split herself in two to prevent Bellum from sealing her away.

In the final boss fights, Ciela provides Link with Phantom Spheres, allowing him to temporarily freeze time. The final scene before the credits is Ciela saying her goodbyes to Link and Linebeck.

Trivia

 * Ciela is the Spanish word for "sky" (although the name can also connotate "heaven"), which is appropriate given the nature of Ciela's character to fly around the screen.