Las year's Proteus is the most experimental and out-there game that appears on this list. The retro aesthetic won't work for everyone, but the dynamically generated environments full of bizarre, surreal and impressionistic signs of life have impressed and soothed many an adventurous gamer.  It only takes a few minutes to complete the game, but as with the famed Minecraft, each time you play it you experience a different world with variance in the arrangement of the numerous creatures and locales.  Proteus is available on Windows, Mac, Linux, PlayStation 3 and Vita.
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