BioWare is trying something different with Mass Effect 3: Omega. After Leviathan, a story-fuelled race around the galaxy that wrapped revelatory new lore around dazzling locations and likeable characters, Mass Effect fans get the opposite. Omega is a dark, hard-fought slog through the belly of the dingy Mass Effect 2 space station. It rambles, it gets lost, and it ultimately feels weightless.
Omega's story centres on angry asari **** T'loak. She's on a mission to reclaim rule following a Cerberus coup (for full details, read the comics). Whether you'll be interested really depends on whether you like the character - this add-on is an entirely separate four-hour diversion from Mass Effect 3's main arc. At no point does anyone else you've met throughout the game's 40-plus hours matter a jot. This is a side-story, a complete digression. There's nothing wrong with that, of course - except that when it's over, everything feels exactly the same.
This may be why BioWare ultimately decided not to include a planned Omega mission in the main game. A different version of T'loak's quest to regain control exists in an early version of the game's script, despite
BioWare's protestations that work on this downloadable content was not started until Mass Effect 3 shipped. Omega is perfect DLC fodder, on the surface similar to Mass Effect 2's Lair of the Shadow Broker. Both campaigns are hinted at within the main game and both feature a well-known character on a personal mission. Yet where Shadow Broker offered up new locations, plot progression and a nifty new base to hang around in, Omega offers none of the above.
Instead, Omega is most comparable to Mass Effect 2's Arrival, a disappointing expansion that saw Shepard leave his team behind and embark on a meandering quest to bridge the story between Mass Effect 2 and 3. Here Shepard isn't even able to do that, and once the excuses are made that he must go alone (**** doesn't like who he travels with, apparently), your squadmates and the Normandy are gone. It's an excuse that barely works in Arrival and serves no story purpose here. Shepard leaves his crack team, only to find himself needing another crack team to retake Omega.