Prince Zuko at first starts the show out with a shaved head except for a ponytail, but as the series continues he first shaves his head and then grows it back. He was originally the primary antagonist of the series, but developed into an anti-hero, and later a protagonist. Zuko had been exiled prior to the beginning of the series by his father, and believed that capturing the Avatar was the only way to regain his honor. Zuko's ancestry reflects his own conflicted nature; his paternal great-grandfather is Fire Lord Sozin , the one who started the war, while his maternal great-grandfather is Avatar Roku .

During his exile, Zuko stumbles upon the newly released Aang but fails to capture him. When Admiral Zhao 's army successfully captures Aang, Zuko helps free him, severing all connections he has to the Fire Nation. As a result, he and his Uncle Iroh flee into the Earth Kingdom , where Zuko bonds with the people his nation terrorized, making friends (particularly among the girls) and going so far as to rescue a town from its corrupt Earth Army guards. After being tempted by Azula 's offer of honor-restoration, he betrays his uncle. After much internal struggle and turmoil, Zuko rejects the Fire Nation[48] and seeks his uncle's forgiveness. He decides to join the Avatar's group to become Aang's friend and Firebending teacher. With Aang, he learns the history behind firebending from the "sun warriors", a pair of dragons who were the original firebenders. During the series finale, Zuko is crowned Fire Lord and ends the war. Originally only a semi-competent Firebender, though still powerful enough to defeat the well-respected Admiral Zhao and prove challenging for Aang to defeat, he becomes far more proficient as the series progresses, eventually reaching a master Firebender's level of skill