The support for in-game DLC means that developers and publishers can now sell their content from within games, rather than only on the Steam storefront.

"DLC can now be added to any game on Steam, regardless of whether it was originally purchased via Steam, at retail, or via other digital outlets," writes Valve. "It is also a feature of Steamworks, the suite of free tools and services available to game developers and publishers."

The Maw: Brute Force and The Maw: River Redirect, two expansion levels, are now available for purchase on Steam for $1.25 apiece.