The tank squad known as the Headless Rabbits, which does not kill people, has its commander, Dorothy, fall to gunfire while upholding their ideals. As Nina and the others sink into sorrow over her loss, the forces of Heidi-Marie begin their invasion. A massive castle floats in the sky, powerful clone soldiers emerge, and organized rogue tanks threaten Unflect with overwhelming military strength. At the same time, a rogue tank arrives in town, bringing something unexpected to Nina and her friends...!? To protect their loved ones and the feelings left behind by Dorothy, the Rabbits resolve to stand on the battlefield once more! With the help of many allies they met in their previous battles, the girls soar high into the skies towards the decisive battlefield!!