Avatar: The Last Airbender Season 2 Episode 8 : The Chase

Aang and his friends are chased by a mysterious machine, which makes it impossible for the group to stop and sleep. The lack of sleep makes everyone irritable, and causes a quarrel between Katara and Toph. Aang acts as a decoy to lure the followers away, but he is cornered by Azula. His friends, plus Zuko and his uncle, arrive to take Azula down together, but she injures Iroh in the moment of distraction and escapes.