Portal 2

Portal 2 is a first-person puzzle game developed by Valve Corporation and released on April 19, 2011 on Steam, PS3 and Xbox 360. It was published by Valve Corporation in digital form and by Electronic Arts in physical form.

Its plot directly follows the first game's, taking place in the Half-Life universe. You play as Chell, a test subject in a research facility formerly ran by the company Aperture Science, but taken over by an evil AI that turned upon its creators, GladOS. After defeating GladOS at the end of the first game but failing to escape the facility, Chell is woken up from a stasis chamber by an AI personality core, Wheatley, as the unkempt complex is falling apart. As the two attempt to navigate through the ruins and escape, they stumble upon GladOS, and accidentally re-activate her...