Released Sep 24, 2014

The Portal 2 soundtrack was released in three volumes: The first, titled Volume 1, was released on May 25, 2011; Volume 2 on July 1, 2011, Volume 3 on Sept. 30, 2011. Track list: Disc 1 1. Science is Fun 02:33 2. Concentration Enhancing Menu Initialiser 02:17 3. 9999999 03:11 4. The Courtesy Call 03:37 5. Technical Difficulties 03:22 6.