Avatar Aang asks his friends to help him honor Yangchen's Festival - an extremely sacred Air Nomad holiday that has not been held in over a hundred years.

However, cryptic visits from the spirit of Avatar Yangchen herself lead Aang to discover a jointly owned Fire Nation and Earth Kingdom refinery - operating on land sacred to the Airbenders! Is this the cause of the pollution Aang finds there, or is something more mysterious happening?

(Source: MU)

This series rejoins Aang and friends for exciting new adventures, beginning with a face-off against the Fire Nation that threatens to throw the world into another war, testing all of Aang's powers and ingenuity.

(Source: MU)