Obsidian Entertainment is no stranger to creating open-world RPGs, especially with Fallout: New Vegas under their belts. However, it comes as a surprise that the studio had a sci-fi Skyrim in the works at some point, but it was ultimately canceled. Obsidian had apparently been collaborating on the game with Bethesda using the latter studio's Skyrim engine.
Based on the design document that has just surfaced, the game was to be an action RPG in the vein of Mass Effect, Borderlands, System Shock 2 and Skyrim—mixed together, that is.
The game was prototyped as Backspace, and its developers put a whole lot of work into the game's design before it was abandoned. It would've taken place on a giant space station ravaged by an alien attack. According to the document, you took on the role of a cyborg who gets caught up in the event and is, for some reason or another, capable of traveling through time between the present day, which is under attack by the aliens, and a decade into the future where the aliens have won.
The design document mentions that skills in the game would've worked the same way they do in Skyrim, by improving over time as you use them, fast-paced gun and melee combat, and a selection of AI companions whom you could "slot" into your suit to provide you with company in the game's mostly solitary setting. Think Cortana from the Halo series.
Fortunately, the studio has not given up on the project and company CEO Feargus Urquhart says that Obsidian may return to it at some point in the future.
Source: Kotaku