Avatar: The Last Airbender/The Siege of the Norh/Recap/Part 1

With his body kidnapped by Zuko, and his spirit adrift in the Spirit World, Aang tries to find the Ocean and Moon spirits to ask for guidance and protection. Instead he finds himself faces the mysterious Face Stealer Koh, the only one with information on the spirits' true forms and location. Sokka, Katara and Yue retrieve Aang's body, defeating Zuko, although letting him live. When they return, however, the Fire Nation have penetrated the walls of the city, and Zhao's mad plan is revealed. He shall take away the tribe's greatest asset, their water-bending, by killing the moon.

Tropes:

 * Ascend to a Higher Plane of Existence:
 * Face Stealer: Trope Namer. And my, is Koh creepy.
 * Meaningful Name: 'Yue' is Chinese for 'moon', which fits how the moon spirit gave energy to save her life as a baby. It becomes all the more fitting when