Turtle Rock Studios, the brains behind Left 4 Dead, have parted ways with Valve for their next project. Publisher THQ today announced that it signed exclusive rights to the studio’s next title, which the company touts as ‘groundbreaking.’

It’s a multiplayer-focused effort, hardly surprising given Turtle Rock’s background. With a 2013 target, the title is still a ways off from release. While it will not be shown off at E3 2011, THQ is promising a full reveal “at a later date.”

“Our quest to sign the best artists and work with the best talent continues,” said THQ’s Core Games VP Danny Bilson. “Turtle Rock Studios is responsible for one of the most original, critically acclaimed co-operative games of this generation, and we are incredibly excited to be working with them on their next project, which looks set to make a similar impact in the multiplayer space.”

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