The Harmony Restoration Movement fails to bring peace, and the nations are plunged back into war. Aang has to somehow mend the rift between himself and Fire Lord Zuko during the midst of the battle, or risk being pressured into killing the apparently renegade Fire Lord. Can war be averted? The fate of Yu Dao and the Fire Nation colonies hangs in the balance.
Gene Yang has stated that Azula's fate will be addressed in the third installment.
He has also stated in an interview with Comics Alliance that the comics will conclude showing a gradual transition between the two animated series.