A unique take on puzzle gameplay by the makers of Half-Life. Portal is a new type of single player game that changes how players approach, manipulate, and surmise the possibilities in a given environment in a manner similar to how the Gravity Gun changed our approach to how an object may be leveraged in any given situation.

Portal was first included with the release of Half-Life 2's Orange Box. Now, each game from that pack is available as its own boxed title for gamers to pick and choose their favorites.

1.7 GHz Processor, 512MB RAM, DirectX® 8.1 level Graphics Card (Requires support for SSE), Windows® 7 (32/64-bit)/Vista/XP, Mouse, Keyboard, Internet Connection