We mopped up the rest of the Orcs pretty easily after that, despite there being four newly summoned Orc Berserkers.
I'm guessing because Katsuki knocked the Off-Worlder out before he could give those Orc Berserkers any orders, they just stood there and did not react at all even when we were trying to kill them.
Before you get the wrong idea, knocking him out did not cause the summons to stop working since the other Orcs he summoned earlier continued to try and kill us.
Lisa told me that the Orc Berserkers being unresponsive was not normal and a summon like this should have the awareness to at least defend themselves. Thus, she suspects that the guy might have messed up the summoning somehow when Katsuki hit him.
We tied the Off-Worlder up and decided to bring him back with us to let the Knights deal with him. He would most probably be treated as a bandit or something.