Valve's user-created content initiative for Portal 2 resulted in more than 35,000 user-created maps and 1.3 million downloads. The Portal 2 Perpetual Testing Initiative was made available to players only two days ago to allow them to create, share, and play Portal 2 puzzles.

Valve's user-created content initiative for Portal 2 resulted in more than 35,000 user-created maps and 1.3 million downloads.

The Portal 2 Perpetual Testing Initiative was made available to players only two days ago to allow them to create, share, and play Portal 2 puzzles. The initiative launched with a simplified Puzzle Maker to allow players to create and directly publish their maps to the Steam Workshop.

To celebrate the launch, Steam is holding a weekend sale offering Portal 2 for 66 percent off, Elder Scrolls V: Skyrim for 33 percent off, and many Team Fortress 2 Workshop items are available for 50 percent off their regular price.

Players can access the user-generated maps through the Steam Workshop. Below is a video of a play-through of one of the top-voted maps created as part of the Perpetual Testing Initiative.