The Portal 2 DLC, “Peer Review” is now available on the Xbox Live Marketplace, Steam, and the PlayStation Network.
This new expansion adds a new co-operative course for P-Body and Atlas, as well as single-player and co-operative challenge modes. The challenge modes feature online leaderboards, so players can compare their skills with gamers from around the world.
(Click the image above to see more Portal 2 screens)
The best part about the Peer Review DLC? Valve has released it, completely free of charge. The add-on will take up 1.37 GB of space on hard drives.
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