Portal 2 is a first-person puzzle video game developed and published by Valve Corporation. It was released on April 19, 2011, for PC, PlayStation 3 and Xbox 360. Portal 2 is a sequel to Portal as well as the first game created by Valve to be rated E10+, compared to the M rating of all of their previous titles excluding the first Portal game and the original Day of Defeat, which were rated T.