A pirates life is hardly uneventful. After the Grand Cross incident and her graduation Marika is immediately thrown into another adventure after meeting a peculiar individual. The crew of the Bentenmaru embark on a grand adventure as they seek a treasure hidden by the Original Seven over 100 years ago.

The Tankery World Championships have come to an end with Ooarai taking the title. However, as they were covering themselves in glory, another club struggled to stay alive. Excalibur Commonwealth Academy's AirCom club will need the help of the Ooarai Tankery Team as both of them join in a world first: The Global Combined Arms: Tankery and AirCom Tourney (CATAC for short)