POTATOSACK
Potato Sack
The Potato Sack is the name of an alternate reality game created by the Valve Corporation and the developers of thirteen independent video games to promote the release of Valve's title, Portal 2, in April 2011. Valve president Gabe Newell envisioned the game as a "Cross Game Design Event" in December 2010, and allowed the developers a free rein to design the game using Valve's Portal intellectual property. The game, requiring players to find and solve a number of puzzles hidden within updates of the thirteen games, ultimately led to the opportunity for players to release Portal 2 about 10 hours earlier than its planned release ...The above text is a snippet from Wikipedia: Potato Sack
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