Cyclonis won. Atmos is at her mercy. The Sky Knights are extinct and the Storm Hawks are divided. Despite all this, Piper is learning the truth behind the war indirectly from the Dark Ace and his original betrayal. The Sky Knight council might not have been as good as they claimed, nor Cyclonia as evil. It's making Aerrow understand that has Piper concerned.
Raph has been told time and time again by Leo and Master Splinter to be careful topside, that every trip could bring danger to their family. Regardless, Raph and Casey decide that they are going anyways. But when they don't heed the warning, they find that bad things really can happen. Enter Bishop 2012.