Portal 2 is a puzzle-platform game developed by Valve. It was released in April 2011 for Windows, Mac OS X, Linux, PlayStation 3, and Xbox 360. The digital PC version is distributed online by Valve's Steam service, while all retail editions were distributed by Electronic Arts.

Like the original Portal (2007), players solve puzzles by placing portals and teleporting between them. Portal 2 adds features including tractor beams, lasers, light bridges, and paint-like gels that alter player movement or allow portals to be placed on any surface. In the single-player campaign, players control Chell, who navigates the dilapidated Aperture Science Enrichment Center during its reconstruction by the supercomputer GLaDOS (Ellen McLain); new characters include robot Wheatley (Stephen Merchant) and Aperture founder Cave Johnson (J. K. Simmons). In the new cooperative mode, players solve puzzles together as robots Atlas and P-Body (both voiced by Dee Bradley Baker). Jonathan Coulton and The National produced songs for the game.