XCOM: Enemy Unknown art director Greg Foertsch conducted a GDC 2013 panel called Art Direction Autopsy: XCOM: Enemy Unknown. Foertsch shared a few internal videos chronicling the different directions considered by Firaxis Games, and was kind enough to share those videos with Joystiq.

Above, you can see a video with a more survival-horror slant - a prototype with methodical pacing, centered around a lone farm house wrapped in dark atmosphere. Jump past the break for two more prototype videos.