Bill Lavoy (Prima Games): Ever since YouTube personality ONLYUSEmeBLADE rose to popularity -- seriously, he has nearly 600,000 subscribers -- Call of Duty players have been going knife only. As popular as it might be, it's something that takes a great deal of dedication. Try to run aimlessly around the map and you'll find yourself at the bottom of the scoreboard in a big hurry. Luckily for you, we've put ourselves through the growing pains so you don't have to. Check out our video below, full of fantastic tips to help you realize your full potential as a knife only purist in Call of Duty: Ghosts.