October 5 will mark the release of “The Sacrifice,” a two-piece DLC pack for both Left 4 Dead 2 and the original Left 4 Dead, Valve announced today.

Detailed last August, the add-on campaign serves as a prequel to “The Passing,” taking place from the perspective of the original game cast — Bill, Zoey, Francis, Louis. Additionally, the finale features a segment Valve has dubbed “Sacrificial Gameplay,” forcing one survivor to give up their life to save the others.

On PC, Valve is releasing the content free of charge to owners of L4D1 and L4D2. L4D1 players will receive the complete Sacrifice campaign with maps playable in Campaign, Versus, and Survival. L4D2 faithful, on the other hand, receive the same campaign with the added bonus of L4D’s No Mercy intro campaign, which has been retrofitted with melee weapons, new infected types, and associated engine enhancements.

Xbox 360 owners of either title will have to pony up 560 MS Points for the content.

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