Portal 2 is a first-person puzzle
game developed by Valve and published by Valve (for the PC and Mac via Steam)
and Electronic Arts (for the PC, Mac, Xbox 360, and PlayStation 3 via retail);
it was released on April 19th, 2011. The sequel plays out over nine chapters
and builds upon the physics-based puzzles of the first game by including a
variety of new gameplay mechanics, such as laser beams that can be redirected
by special cubes, zero-gravity funnels that can be redirected by portals,
launch pads, and paint-like substances that change the properties of the
surface it covers.
