Valve, creators of best-selling game franchises (such as Half-Life and Counter-Strike) and leading technologies (such as Steam and Source), today announced the free Portal 2 DLC titled "Perpetual Testing Initiative" will be available for the PC and Mac on May 8th. The "Perpetual Testing Initiative" allows players to easily create, share, and play Portal 2 puzzles. The Initiative comes with a simplified puzzle maker that allows that creation of mind-bending puzzles without ever leaving the game. The puzzle maker can directly publish maps to the Steam Workshop where users can browse, vote on, and select to play them. Selected puzzles will automatically be downloaded and installed inside Portal 2. Portal 2 holds a Metacritic score of 95% and has been awarded numerous Game of Year awards. It features expansive single and cooperative multiplayer game modes. For more information on Portal 2 and its downloadable content, please visit http://www.thinkwithportals.com.