After hyping the game up for years, Valve finally released Portal 2 for PC, PS3, and Xbox 360.

The final part of Portal 2′s hype campaign allowed would-be players to unlock the game early by playing a specific set of thirteen indie games sold in a bundle on Steam on April Fool’s Day. Players worldwide came together for the cause, with their efforts leading to Portal 2 releasing ten hours ahead of schedule.

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