Portal 2 is a first-person puzzle-platform video game developed by Valve Corporation. Released in 2011, it is a sequel to the original Portal game. Players control Chell, who navigates through a series of test chambers using a device called the Aperture Science Handheld Portal Device, which creates linked portals on flat surfaces. The game features a rich narrative and introduces new characters, including Wheatley, a personality core, and Cave Johnson, the founder of Aperture Science. Players solve puzzles by manipulating physics and using the environment, while uncovering the story behind the facility and its experiments.