Two images appeared on the Mass Effect Facebook page recently, via the Twitter accounts of prominent producers of the series, Casey Hudson and Mike Gamble. One image depicts what looks to be some of the lower, more seedy, levels of the Citadel. The other image is much more straight-forward: a Krogan with a large hammer. Fans and media have both speculated that these images are teasing the final piece of single-player downloadable content for Mass Effect 3, and additional multiplayer content.
With shows like GDC and E3 on the horizon, and Mass Effect 4 development confirmed and seemingly increasing with each day, it would not be a surprise if attention on additional content for Mass Effect 3 begins to dwindle. The aforementioned images can be viewed below.