Back in June at the 2014 E3, Alien Isolation was demonstrated on the Oculus Rift DK2 to gamers and journalists alike, who were all blown away by its horror, graphics and atmosphere. It almost seemed certain that the game would be playable on the headset on release; but alas, SEGA chose not to support the Rift. That wasn't the end of the story, however.
It was clear that support for the Oculus Rift DK2 was added during its development, so immediately after the games release on September 7th, the folks at /r/Oculus began to dig through its code to see if any traces of Rift support were still remaining; and as it turns out: yes there was!
Findin the game's DATA folder. Change the stereo options to:
<Setting name="Stereo Mode">
<Quality name="Rift" precedence="4"/>
<Quality name="Off" precedence="4"/>
Next you'll need to set the Oculus to extended mode, and use the configuration utility to pause the service. Start the game, then reactivate the service by setting the display mode to "Direct to Rift".
Thanks to the positional tracking, you'll be able to pop your head around corners to see if there's a giant, unstoppable murderer coming at you. Have fun that.