A spin-off for the Nintendo DS titled Mass Effect: Corsair was in early development but ultimately cancelled. The reason for its cancellation was due to high production costs for the DS game cartridge, according to ex-BioWare producer Mark Darrah. EA predicted the game would only sell 50,000 units with each cartridge costing $10.50 USD to produce.

Corsair would've been a combination of the games Privateer and Star Control set "in a part of the galaxy that was more piratey and not really fully explored". You'd play as an independent character exploring, collecting cargo, and selling information to the Human alliance. The development team had already started working on the flight controls and overall story before it was cancelled.
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