* The single-player portion of Portal 2 introduces dynamic characters, fresh puzzle elements, and a larger set of devious test chambers. Players explore areas of the Aperture Science Labs and reunite with GLaDOS, the murderous computer companion.
* The two-player mode features a separate campaign with unique story, test chambers, and two new player characters. This mode forces players to reconsider everything they thought they knew about portals.
* Advanced use of physics allow for the creation of a whole new range of interesting challenges, producing a much larger but not harder game.
* A massive sequel to the title named 2007′s Game of the Year by over 30 publications worldwide.