BioWare doctor-bosses Greg Zeschuk and Ray Muzyka have hinted that a multiplayer mode could still feature in Mass Effect 2.
"Well, we haven't disclosed a feature set at this point," Doctor Greg told MTV Multiplayer, when asked if there are plans to support co-op in the game.
Doctor Ray interceded: "But multiplayer is something that, at a broad level, BioWare is interested in exploring in our games in the future."
"Yeah," continued Doctor Greg, "[multiplayer] has to be central to the game to make sense. I think you see examples of games that have thrown in multiplayer modes that don't make any sense and then you see games that are built from the ground up as co-op experiences."
BioWare has offered relatively few details for Mass Effect 2. We do know, however, that game-saves will be reusable across the trilogy. But exactly how is to remain a "mystery" for the time being.
One obvious effect will be the impact of pivotal story-decisions during Mass Effect 1. A central character killed because of your actions will remain dead in Mass Effect 2, for example. But there are also plenty of unexpected twists and turns along the way.
"Yeah, we actually get gasps and things. Because you don't know what you're going to see, and I guess that's the thing about the games we make. We always want that unpredictability to always be a part of that experience," said Doctor Greg. "Because with shooters, you have all these bad guys and then eventually you shoot the boss at the end - you know what's going to happen.
"What we make is purposefully designed, and you'll see it in both Mass Effect 2 and Dragon Age: Origins. It's getting more and more grey and complicated in terms of who's the good guy? Who's the bad guy? It's not as clear, and I think that it's exciting to make entertainment that's got mature themes.
"There's also mature writing, the complexity," he added. "I think our industry gets a lot of knocks on the quality of the stories, but there are certain examples of where it's really progressing. We think our stuff is one [example]."
Fan feedback, Doctor Ray went on, played an important role when addressing gameplay mechanics that worked in Mass Effect 1, as well as those that didn't.
"So some of [the changes are] about amping up the intensity; ME2 is an RPG but it's a shooter-RPG. We're really focusing on the intensity of the action experience," said Doctor Ray. "Also, tightening the exploration. Uncharted worlds, they're still optional, but we want to make all of them feel important and feel like they're all augmenting and improving your main passage through the game. You're going to really feel rewarded for having gone through them. It's a much tighter experience as a result.
"Moment-to-moment intensity - being able to grab control of the conversations - we didn't do in the first game. Small things too, like reducing the elevator speed times and things like that. Those are important to fans. We recognise that.
"Mass Effect 2, I'm really excited about it," he added, "because it's really taking the Mass Effect franchise to another level."
Mass Effect 2 will be out on Xbox 360 and PC next year.