This achievement requires that you kill 10 enemies in a row without firing a bullet and can ONLY be earned in MULTIPLAYER. Attempt this achievement while you are going for "Survivor" to kill two birds with one stone. This can be earned across multiple games, game modes, and ranked or custom matches. It does not need to be done in the same match, as long as you don't fire a bullet at all. You will need at least one other player and they must be on the other team for you to kill them. Avoid random players that might unknowingly ruin your boosting session by playing a less popular game types like Manhunt.