Little Big Planet is a solid 4 player co-op title where players can work together to platform their way through dozens of levels. Once they get tired of that? Players can cooperative and create their own levels using the in game tools and then share them online. The game supports both online and local co-op play - including drop-in/drop-out support.
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*Note* - This it the PAL version of the game that works in any PlayStation 3.