The Kingdom of Arandas and the Countries Unification of Ingelmia have been embroiled in a lengthy war. The impenetrable fortress of Great Wall stood firm until it unexpectedly opens, transforming the conflict's trajectory. As a new soldier, Susumu Tokimune anticipates his debut battle with enthusiasm. Disregarding potential entrapment, he leads his team into a fatal confrontation with Jamie Hazaford, an engineer and the skilled operator of the legendary weapon, Argevollen, also known as the Silver Trailkrieger. Their encounter transpires in a domain where battles are routine. However, it will significantly impact Tokimune's Independent 8th platoon's fate and the war's direction, shaping the future of all those involved.