Time Rifters is an game designed for use with the virtual reality headset Oculus Rift but it has another feature worth noting. Something called single-player co-op.
Single-player co-op is one of those indie title terms that gets bounced around every few months but this short demo video for Time Rifters does a good job of explaining what it's all about. Gamers get four lives which all exist at the same time, players take turns controlling each of these lives to bring down some nasty polygonal monsters.
Gamers need to plan out their attack and use the other lives – called “time clones” in the game - to carefully take out the bad guys with different sets of weapons. While Rifters was designed for the Oculus Rift you can still play it on your regular old monitor by trying out the demo here.
Time Rifters is currently sitting in Steam Greenlight section and if you're lucky enough to have an Oculus Rift grab it and go wild.