Left 4 Dead Survival Pack Unveiled

The long-talked-about, much-anticipated Left 4 Dead expansion pack, first mentioned on Kotaku, hits the PC and Xbox 360 this spring.

The L4D Survival Pack introduces a new multiplayer game mode entitled, Survival, plus two complete campaigns for Versus Mode, Valve announced today. They also say that a Critic's Choice Edition of the game is heading to retail stores this spring, and will include access to all the content introduced in the L4D: Survival Pack.

In addition, PC gamers will be able to get their hands on the first Left 4 Dead release for the Source Software Development Kit which will allow the creation of custom Left 4 Dead campaigns that will be discoverable via L4D's matchmaking system. The SDK update is also due for release this spring, and is free of charge to all owners of L4D on the PC.

"Since Half-Life launched in 1998, Valve has made continuous efforts to expand the offering of its products beyond what's included on the day of launch," said Gabe Newell, co-founder and president of Valve. "With Half-Life and Counter-Strike, and more recently Team Fortress 2, we've learned that we're no longer making stand-alone games but creating entertainment services. With Left 4 Dead we're extending that tradition by creating additional gameplay and releasing our internal tools to aspiring developers so they may also create and distribute new Left 4 Dead experiences."

OK, you can run around shouting now.