S1·E13 The Queen of Battle is Infantry.

The members of C³ finally battle it out?! That's right... the big event is about to begin. They call it the "Field Queen Contest"! And not only are the members of C³ participating, but Aoi and Rin, as well! Each contestant shows off her individual charm during the appeal time event, and then they all face each other one-on-one in an elimination-style survival game battle! Who will take home the victory, and what lies at the end of this battle between passionate young girls?