The Twist will be that Aang never woke up from inside that iceberg. The entire movie will be a hallucination in his head, as he and Appa slowly freeze to death. The Fire Nation will eventually win the war and kill off the next Avatars as the pop up, until the reincarnation cycle swings back to Air Bender. Being as there are no more Air Benders, the cycle dies and the world is doomed to forever be at the grip of the Fire Nation. The End.
