Koh the Face Stealer is a primal spirit that feeds on lost souls in the spirit world and Aang has to find a way to defeat him.
Team Avatar notices a patch of the forest that has been burned down and they fly over to check it out.
They find out from a village nearby that the Fire Nation army just cleared their path and some of the villagers recently disappeared in the forest.
They claim that something is wrong with the forest’s spirit so Aang decides to investigate.
They find a shrine and Aang travels to the spirit world but brings Katara and Sokka. They are advised to stay on the path but get separated by the angry spirit of the forest.
They are then enveloped by the Fog of Lost Souls where they are taken back to the memory of their lowest moment.
A reminder of tough times
Katara is taken back to the moment her mother was killed and she has to relive every second of it.
She partly blames herself because the soldiers were looking for her and her mother sacrificed herself to save her.
Sokka returns to the day he passed his ice-dodging trials. He barely managed to make it and afterwards, he overhears his father say that he’s disappointed in Sokka’s ability.
As Sokka and Katara buckle with the grief of these moments, a spirit crawls up to them and tells them to give in.
Aang sees a vision of his home but reminds himself that he’s in the spirit world and the vision isn’t real.
Koh the Face Stealer reveals himself to Aang and says that he’s looking forward to feeding on Aang’s friends and the villagers who were lost.
When Koh realizes that Aang is the Avatar, he asks if they are here to return what they stole. They also take on the face of the loved one they stole from one of Aang’s predecessors.
Avatar Kuruk later says that his partner’s face was stolen by Koh when he waged war against the spirits.
History with Avatars
Aang meets Gyatso who tells him that Avatar Roku was rumored to have defeated Koh so Aang goes to Roku’s shrine in the Fire Nation for help.
Roku says that he didn’t defeat Koh, he stole the totem of the Mother of Faces, Koh’s mother.
According to Roku, Koh just wants the connection to his family back, just like how everyone else wants.
Aang asks for the totem so that he can use it as a bargaining chip for his friends and the other villagers.
Koh accepts the return of the totem and sets everyone free.
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