Developed by Obsidian, it will be a fully-fledged role-playing game for Xbox 360 and PlayStation 3, according to Game Informer.
As a new kid arriving in South Park, you must make friends and defend the town from a number of threats and dangers.
Show creators Trey Parker and Matt Stone will be writing the script, performing dialogue and overseeing the project's development.
South Park got its own tower defence game on Xbox Live Arcade in 2008.
South Park: The Game will be available sometime in 2012.
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