BattleBlock Theater is a former XBLA exclusive and is now coming to Steam with a host of new features. BattleBlock Theater closed Beta will be from from March 24, 2014 to March 31, 2014 and you must register here for a Beta Key. BattleBlock Theater is from the developers Behemoth who also developed Castle Crashers.
-Weapon switching! Players can now switch between a primary and secondary weapon in game!
-New Cat Guard enemies throughout Story Mode.
-Steam Workshop integration for sharing user created levels.
-Steam Inventory integration for trading! This allows users to trade and sell weapons, prisoners, gems and yarn via Steam.
-X input, Direct Input, and Keyboard/Mouse support.