Portal (2007)

[User Summary] Portal is a single-player action/puzzle game developed by Valve Corporation. The players are tasked with working their way through a dangerous test facility. To do so, they will be using a "portal gun" to create doorways by which they can maneuver around the environment. The game makes use of puzzles involving manipulating objects, physics, re-directing projectiles, and much more. The end result is a puzzle game like no other.