Portal 2 - Greatest Hits for the Sony PlayStation 3 is a critically acclaimed puzzle-platformer game developed by Valve. Players use a portal gun to create interconnected gateways on flat surfaces, navigating through a series of increasingly complex test chambers. The game is set within the mysterious Aperture Science Laboratories, and features a darkly comedic story that unfolds through interactions with GLaDOS, the AI antagonist. The single-player campaign is complimented by a co-op mode where two players solve puzzles together. Its inventive gameplay, engaging story, and quirky humor define its genre.