Avatar: The Last Airbender is populated by a wide assortment of layered characters who travel various personal journeys over the course of the series, but one of the most interesting is that of Fire Nation prince Zuko, who at one point has to deal with the loss of his abilities.
Prior to the beginning of the series, Zuko was exiled after refusing a command to duel his father the Fire Lord after he had the temerity to suggest that endlessly sacrificing soldiers in the Fire Nation’s invasion of the Earth Kingdom perhaps wasn’t the wisest military strategy. To prove his worth, he vowed to capture the Avatar and spent the next three years searching for him, driven by anger at himself, his father, and Aang.
After he eventually realizes he will never be worthy in the eyes of his abusive father and that seeking honor as a substitute for love will only lead to compounded misery, he joins Team Avatar in their attempts to put an end to the century-long war ravaging the world. However, his epiphany also results in the loss of his firebending, as the ability comes from its wielder channeling anger and hate towards their enemy, and with Zuko managing to let go of the rage that previously drove him, there is little else with which he can fuel his talent.
His defection solves the lingering problem of who would teach Aang firebending, as tutors would be a challenge to locate within a hostile nation, but the loss of Zuko’s own capabilities limits his effectiveness. It’s only after the team locate the last of the dragons and learn that the original source of firebending, before it became corrupted, was to perceive fire as pure energy and the spark of life rather than a force for destruction, that Zuko’s ability returns along with his being able to train Aang to firebend in the young boy’s final step towards truly becoming the Avatar.
The complexity of Zuko’s motivations mark him as one of the most compelling characters in Avatar: The Last Airbender, and it’s through the resolution of his tangled web of emotions, along with the loss and regaining of the ability that he let define him, that he is able to realize his own destiny of aiding in bringing about world peace.