Valve's official announcement regarding DLC for Portal 2 was quickly followed by the news that it would be free on all platforms this summer. Valve was tight lipped on specifics, but we do know at this point it's called Portal 2 DLC #1 and will contain “new test chambers for players, leaderboards, challenge mode for single and multiplayer modes, and more." Challenge mode was hinted at being similar to the Challenge Maps in Portal: Still Alive on Xbox Live Arcade.
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