tip: when getting head shots, you must line up the very center of the crosshairs with the bugs head, not hit it's head with the edge of the AOE. this makes it much easier than anticipated to get anvilator and Head Hunter.
at first i was doing what people said, throw random stuff on till u get a good result, bu AT LAST, I UNDERSTAND HOW THE STUFF EFFECTS EACHOTHER! my win rate just went up about 9001%.