Navi is a blue fairy that looks like a glowing blue sphere with wings.
Navi was the "guide" to the hero of Hyrule before Link. She is extremely annoying. She appeared suddenly in the stadium and won't leave Link alone. She was being chased by Volvagia because he couldn't stand her any more.
She wasn't seen since the team for Operation:Devastation was formed. During this mission, she "befriends" Volvagia and Epona.