As of February 2019, the series consists of two installments, one of which is currently only available to hear at S. D. Smith's Green Ember LIVE.
It is generally understood that the series will be composed of a few books set either slightly before or during the events of the main series, most likely from a different point of view than of the characters from which the main series was written.
So far, the series consists of two installments: The Last Archer, which dealt with the point of view of Jo Shanks during the events of The Green Ember, and Potter's War, which follows the misadventures of Eefaw Potter shortly after the events of The Green Ember.
"A Green Ember story set during Heather and Picket's arrival at Cloud Mountain, The Last Archer follows the journey of Jo Shanks. Jo is a gifted archer with a burden on his back and a fire within. Eager to see the Longtreaders receive justice, he travels from his Halfwind Citadel home to a Cloud Mountain poised on the brink of war. What he finds there will confront his convictions and test his resolve as the war begins and King Jupiter's heir is revealed. A kingdom in the balance. An arrow aimed at the heart of darkness. Who will take the shot?"