From a lore standpoint, many races were missing in Mass Effect: Andromeda. Among these, the Quarians, a nomadic species known in the Mass Effect universe for their technology.
The Quarians did not appear in Andromeda, supposedly because their Ark didn't get to the new galaxy yet. Interestingly, the briefing of the latest Apex multiplayer mission (due to expire in a day or so from now) mentioned that very Ark, which sparked hopes among fans for a Quarian-centered DLC.
[DATA: Raw signal transmission received by Remnant observatory. My analysis accounts for attempted auto-translation by Remnant systems and data fragmentation.
ANALYSIS: "…trying to boost the signal. Unknown if… tech seems to be helping even if we don't know the… back to Keelah Si'yah. …way home."]
This would be somewhat surprising. After all, Mass Effect: Andromeda turned out to be a disappointment when compared to the original trilogy.
In our review, Francesco wrote:
Mass Effect Andromeda could have been one of the best RPGs ever, but sadly the game never realizes its full potential. While the gameplay experience and RPG mechanics are mostly well done, with the best combat system of the entire series, the predictable story, uninteresting characters, and generally mediocre writing make the Pathfinder's quest to find a new home for humanity not as memorable as it could have been.
Earlier this month, Kotaku even reported that Bioware Montreal had been downscaled in size, becoming a mere support studio, while the Mass Effect IP as a whole would go on a hiatus of sorts.
A single player DLC based on the Quarians species would factually contradict this report. If any such plan exists, we should know about it during EA Play's keynote, scheduled for Saturday, June 10th at 12 PM Pacific Time. Stay tuned.
