Valve announced sales results and multiplayer numbers for its zombie apocalypse, co-operative action, Left 4 Dead 2.

Released just two weeks ago, over 2 million retails copies of L4D2 have been sold worldwide and the game appears to be on target to become one of the top selling Xbox and PC titles for the month of November. Sales to date are more than double the original title, which was released exactly one year prior to L4D2. And "Black Friday" promotions during the title's second week of availability in North American resulted in stronger than expected sales in L4D2's bid to become one of this year's best selling releases on both platforms.

"Left 4 Dead 2 is off to a great start with strong support at retail and great reviews from the press," said Doug Lombardi, VP of marketing at Valve. "Meanwhile the title has already been played by over 1 million Xbox LIVE Gold account holders, and news regarding L4D2 DLC 1 is coming very soon."         

Exclusively available for the Xbox 360 and PC, L4D2 sets a new benchmark for co-operative action games. The title adds melee combat to enable deeper co-operative gameplay, with items such as a chainsaws, frying pans, axes, baseball bats, and more.

With the AI Director 2.0, L4D's dynamic gameplay is taken to the next level by giving the Director the ability to procedurally change weather effects, world objects, and pathways in addition to tailoring the enemy population, effects, and sounds to match the players' performance. The result is a unique game session custom fitted to provide a satisfying and uniquely challenging experience each time the game is played.

Finally, with new Survivors, boss zombies, weapons, and items, Left 4 Dead 2 offers a much larger game than the original, featuring more co-operative campaigns, more Versus campaigns, new Survival maps, and the new competitive game mode, Scavenge, all available at launch.

For more information, please visit www.l4d.com.

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