Heavy Crit chance and Crit damage build. Up to 584% crit chance, as long as you sustain your headshots and don't miss any part of the body afterward so that you don't lose 100% crit chance for missing all burst shots. If you switch fire modes, you'll have to build up all of your crit chance again on [Critical Precision]. With 12x crit damage multiplier, along with increasing damage thanks to deadhead and the crit damage increase from the crit chance tier, you'll be getting LOTS of damage off your crit shots.