Valve is to release free Portal 2 singleplayer and co-op content for PC, PS3 and Xbox 360 on October 4.
In Portal 2: Peer Review, “you and a friend will continue the story of loyal bots P-Body and Atlas as you puzzle your way through a mysterious new co-op test track and once again match wits with GLaDOS.
“The DLC also features a single player and co-op challenge mode, and leaderboards to compare challenge mode scores with friends and the Portal community.”
Peer Review, which was originally scheduled for a summer release, will be available to all owners of Portal 2 for download on PS3 and Xbox 360, and will be automatically downloaded via Steam on PC and Mac.
The first Portal 2 DLC released in June, but was only available with Razer's Hydra motion controller, through Steam for $140 / €140. It featured 10 new levels developed by Sixense Studios, not Valve, which involved portal rotation and object resizing.