Promised way back in February, the Source SDK for Left 4 Dead has finally been released to the masses in beta form, offering aspiring designers the chance to let their imagination run wild and conjure up a zombie apocalypse from the ground up. Distributed as a free download to all owners of the game, it can be found under the “Tools” tab in Steam.

The kit consists of “modified versions of the same tools” Valve used to develop L4D, making the possibilities endless. Users can create their own campaign maps, character skins, 3D models, sound effects, and music.

Currently there is no “official” way for end-users to play these custom maps, but fret not: Valve plans to roll out an update to the matchmaking environment “in a few weeks” to support such creations. Around that time, instructions detailing how to package up maps for public distribution will be released.

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