Upotte!! S01 E10 And Then! Upotte!

"Forget about girls with guns. These girls ARE guns!"

The girls have split up into two teams, Ichiroku/Shigu and Funco/Eru. The goal is to flank the attackers in the train station. Ichiroku gets hit by a shotgun blast and Eru’s magazine catch is damaged. What is the attacker’s endgame?