Leaf is the Spirit of Power, one of the three spirits who are required in order to track down the Ghost Ship in Phantom Hourglass. He is the first spirit that Link rescues in the game, and is freed from the seal that was placed on him upon the defeat of Blaaz, the boss of the Temple of Fire. His powers can be used to open a sealed door inside the Temple of the Ocean King, allowing Link to delve further into the temple in search of clues as to the locations of the other spirits.
Leaf's power can be upgraded by collecting Power Gems and bringing them to the spring on Spirit Island. This permits him to act as an equippable fairy guide to Link, in place of Ciela, causing the hero's sword to become wreathed in flames and allowing him to deal more damage to enemies, and even stun nigh-invincible foes such as Phantoms and Reaplings.
- Leaf is unique for being one of the only male Fairies seen in The Legend of Zelda series. The other is Tael from Majora's Mask.