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5.1 Surround Sound, HD (High Definition). Winner of over 30 ‘Game of the Year’ awards, ‘Portal’ now comes to Xbox LIVE Arcade! As unwilling test subjects in a sinister laboratory, players must break the laws of physics using ‘portal’ technology to solve puzzles and survive. Featuring a darkly comic story that weaves adventure with brain-bending puzzles; ‘Portal: Still Alive’ also introduces 14 brand new bonus puzzles to challenge even the most skilled test subjects. Players can also get a glimpse into the making of ‘Portal: Still Alive’ with commentary from the developers. Good luck! This game requires the Xbox 360 hard drive.

5.1 Surround Sound, HD (High Definition). Winner of over 30 ‘Game of the Year’ awards, ‘Portal’ now comes to the Xbox LIVE Arcade! As unwilling test subjects in a sinister laboratory, players must break the laws of physics using ‘portal’ technology to solve puzzles and survive. Unlock the full game to experience the complete singleplayer story, gain access to all 14 new bonus maps, and get a glimpse behind the scenes with developer commentary! This game requires the Xbox 360 hard drive. There are no refunds for this item. For more information, see www.xbox.com/live/accounts.