[Mik]

OK I got one, it was in single player mode on hardcore level, though:
So, all of my teammates were down. I was crouched down behind a single block for cover. All of the locust were behind a long block, all shooting at me. I pulled out my sniper rifle and headshot one grub. I got an active reload and blind-shot a grub that was kamikaze rushing me. Then I pulled out a grenade, bounced it over their cover and closed the grub hole and killed one locust. Now there were just two left. The first one I headshot, but he had a helmet, so I did an active reload and headshot him again. The last locust began rushing toward me right before I killed the other locust. I switched to my lancer, and shot his knees out. Then I just walked up, and curbstomped him. =)