Mass Effect 3: Omega will release on November 27, BioWare has announced.
Set during the time of Mass Effect 3, the latest piece of single-player DLC follows the tale of "Pirate Queen" Aria T'Loak as she battles for control of Omega against General Petrovsky.
The DLC will also introduce a new female Turian character, thought to be called Narim.
"Omega's our latest piece of DLC," Mass Effect 3 producer Mike Gamble said during an interview at Comic Con. "It's one of our largest that we've done so far. It's basically double the size of the largest DLC we've done for Mass Effect 3.
"It takes you through all the different areas of Omega that you've ever wanted to go through. [There's] a whole bunch of new enemies, [and] a whole bunch of new challenges for the player."
The content will cost 1200 Microsoft Points or $15, Gamble confirmed.
Mass Effect 3: Omega was originally uncovered by dataminers searching the Mass Effect 3 disc.
Files contained on the disc suggested that one of Mass Effect 2's lead characters, Zaeed Massani, would also be making an appearance in the DLC.