Six: FTL
FTL is one of the year's most monumental gaming achievements, but in a way that's difficult to describe. It doesn't fit within, nor does it subvert, conventional genres, and it doesn't do anything daring with narrative. So here's what makes it special: it's one of the very rare games I would recommend to virtually anyone without any reservations. “You like games? Try FTL.” (the only caveat: people who would have difficulty pressing pause during tense situations)
It's like Star Trek: Voyager if Voyager had been awesome. It's an RPG where you play as a spaceship. It's quite simple once you start playing it, with a RTS-style interface to move your crew around and a slow escalation of complexity of ship systems. Its difficulty, procedural content, and permanent death make it a fantastic game for creating new and different stories each time it's played.