The Empire's Imperial Army has invaded Gallia. A young man, Lt. Welkin Gunther, the son of the late Gen. Belgen Gunther, forced himself to enlist in the militia and forming Squad 7, making him the tank commander/1st Scout leader where he commands a battle tank "Edelweiss" and driven by her sister Isara Gunther who joins as the mechanic. Also joining him are over 50 units including Alicia Melchiott, the girl whom Welkin met just before the attack of the Imperial Army and a 2nd leader of the Scout units. Brigitte "Rosie" Stark, a former bartender and singer and the leader of the Shocktrooper units. Largo Potter, the leader of the Lancer units. Welkin must use all his strategies and put an end to the war.