Avatar Aang asks his friends to help him honor Yangchen's Festival--one of the highest Air Nomad holidays, which hasn't been celebrated in over one hundred years.

But 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 a more mysterious menace afoot?

• The official continuation of Airbender from the original series creators!

• Continues to top the sales charts!

• The perfect companion to The Legend of Korra!

"One of the best new pop culture mythologies to debut in the last decade."--Kotaku

"A fantastic glimpse into the post-series universe."--Bleeding Cool