Looks like Mars' moon Phobos will be a playable location (Destiny)

by HavokBlue, California, Tuesday, July 08, 2014, 12:43 (2700 days ago) @ Yapok

Phobos and Charon will both be playable locations.

Titan as well, if I'm not mistaken.

There were screenshots (albeit tiny low-quality ones) for these locations in the selfie radio broadcast thing they did on twitter a while back.

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