For the most part, "Doom 3" is a single-player game. Multiplayer elements will only support up to four players, a minuscule number when compared to many of today's action games. The clever use of lighting and the more precise target areas will help it stand out, though. (While in previous games a shot in the general vicinity of your opponent would suffice, you'll have to aim a little more carefully now. It's literally possible to shoot under another character's arm.)