Black-Wolfing
When a player in an objective-based multiplayer FPS game makes a point to position themselves to an area of the map near the opponent's spawn, shooting passersby in the back. This is done with the express purpose of preventing players from getting to the objective, sometimes the "Black-Wolf" will position themselves near a potential spawn location long before the opposing team has started spawning there.
watch out for JackFrags, he's Black-Wolfing near the next A site spawn again