It was one of the biggest games of the year, and now - according to comments made on the internet over the weekend - the sequel is already under way.
"We're in early stages of designing a completely new Mass Effect game. What would you want to see in it?" tweeted Casey Hudson, executive producer of the Mass Effect series, to his 30,000 followers on Twitter.
While no further details have been given as to when we might be able to play Mass Effect 4, or what a possible storyline could be, feedback from Hudson's followers suggest people want to be able to play alien races in the new version.
READ: Mass Effect 3 review
Mass Effect 3, launched earlier this year, caused a huge stir with gamers after a rather disappointing ending to what, at the time, was perceived to be the last in a trilogy.
That forced Hudson and the games developers to release a re-write of the ending that didn't paint such a bleak picture.
Given the nature of the ending of the game (no spoilers, don't worry), we would hope that the new game will either go the way of Star Wars and concentrate on a time before Commander Shepard and the Mass Effect Relays, or go way, way, way into the future.
The comments follow an interview by Fabrice Condominas at BioWare Montreal in which he said the game would continue with a new hero.
“This is really our starting point. Now the Mass Effect universe is vast, and very, very rich. So at this point in time, we don’t even know what kind of time frame we’re going to be in. All we’re doing is more gathering ideas from the teams, gathering feedback to see several things," Condominas told VG247 in October.
“So first, we don’t want to make ‘Shepard 2′, or Mass Effect 4 with like, ‘Oh there’s no more Shepard but you’re a soldier in the universe’. So this will be a very, very different context for sure, and nothing has been decided on the rest.”
It's also worth noting that such a game is likely to be being developed as one of the lead titles for the new Xbox console, currently dubbed the Xbox 720. It is expected to be announced in 2013, and be in the shops either later that year, or 2014.