“The Sacrifice” — the new add-on for Left 4 Dead (L4D) and Left 4 Dead 2 (L4D2) – as well as Left 4 Dead 2 for the Mac are available now via Steam, a leading platform for Mac and PC games with over 25 million accounts worldwide.

The new DLC is available free of charge to all Steam gamers who own a copy of L4D and/or L4D2. And, for a limited time, L4D and L4D2 (as well as their respective Steam bundles) are available for 66% off the regular price.

“The Sacrifice” is the prequel to “The Passing,” and takes place from the L4D Survivors’ perspective as they make their way South. In addition to advancing the story, “The Sacrifice” introduces a new style finale featuring “Sacrificial Gameplay” where players get to decide who will give their life so the others may live.

The Sacrifice DLC for L4D1 is a separate download than The Sacrifice for L4D2.

In The Sacrifice for Left 4 Dead 1 gamers receive the complete Sacrifice campaign with maps playable in Campaign, Versus, and Survival.

In The Sacrifice for Left 4 Dead 2 owners receive “The Sacrifice” campaign playable with the Left 4 Dead Survivors. In addition, those with Left 4 Dead 2 receive L4D’s “No Mercy” campaign. Both campaigns are playable in Campaign, Versus, Survival, and Scavenge modes and both will feature the Left 4 Dead 2 Special Infected, items, and weapons. Yes, Zoey with a chainsaw!