Ash and Alain continue their battle against Lysandre. They were successful in defeating Lysandre. Meanwhile, Chespie was absorbed by the Megalith Crystal in Lysandre Labs, which transforms into a giant Megalith Zygarde. The Megalith Zygarde was headed towards Anistar City to absorb the power from the Anistar sundial. This will result in a planetary apocalypse. Ash, Clemont, Alain, Malva, Steven Stone, the Kalos Gym Leaders, and the Kalos League Champion join forces to defeat the Megalith Zygarde.