Ash decides to cooperate with Xiao in order to thwart Luther's ambitions. After Ash is shown remnants of Luther's experiments, Xiao tells him about Luther's goals and explains how Xion is the key.
"Quest 12: The Past and Future" 
Folge 12: Vergangenheit und Zukunft
MISIÓN 12: EL PASADO Y EL FUTURO
ÉPISODE 12
LE PASSÉ ET LE FUTUR