Mass Effect 3 is going to have a multiplayer mode in “Galaxy at War.” However, Mass Effect 3 creative director Casey Hudson indicates that BioWare has been looking for ways to put in multiplayer since the first game.

“To us it was always a fun, intriguing idea to partake in the Mass Effect universe with friends, to look around, kind of see it from inside with others rather than just taking part in this solo experience,” he explained.”In general, that’s the direction that videogames are heading; they’re more social, more online, and we’ve been trying to find a way ever since Mass Effect 1 to integrate some kind of multiplayer.”

“In those early days we were trying to figure out what kind of a game it was going to be, and were thinking of ways that maybe the whole story experience might revolve around a co-op (structure),” he added. “That, instead of there being just one Commander Shepard, he’s in fact kind of lots of different heroes that can jump in, meet each other and interact. And by embarking upon that route we realized there was just a lot of things we simply couldn’t do, or had to compromise when ensuring the solo experience was as great as we wanted it to be, so we dropped that idea and proceeded to perfect single-player, to make it really solid.”

“Then, with ME2 we revisited the idea, deliberating whether you could perhaps take control of one of the other characters for a while, but – again – there were a lot of factors that would have compromised the single-player story,” he noted. “So the difference really was that, with ME3, we adopted a fundamentally different approach to what the thing is about, which is that there is a whole intergalactic war going on, which wasn’t the case in the previous entries . . . That provided us with a different idea; now in multiplayer you can play as that crew of special forces, journeying around and helping Shepard with the war effort.”

Source: CVG