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Season 1 - Feb. 21, 2005
Season 2 - Mar. 17, 2006
Season 3 - Sep. 21, 2007

Avatar: The Last Airbender Season 3 Episode 20
HD
Overview:
Sokka, Suki, and Toph try to stop the Fire Nation’s air fleet. Meanwhile, Zuko and Azula duel in an Agni Kai and Aang confronts the Fire Lord. On the verge of losing, Aang gets hit in the back of his scar which sends him into the Avatar State.
Serie name Avatar: The Last Airbender
Episode name: Sozin's Comet (3) - Into the Inferno
Air Date: 2008-07-19