Left 4 Dead 1's new downloadable content, Crash Course, will be available by September 23, if Microsoft's to be believed.
The new campaign - which bridges the gap between the end of the No Mercy campaign and the beginning of Death Toll - is being pimped for a Game With Fame event next week, which usually sees XBL gamers humiliate a celebrity.
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"If you're an Xbox Live Gold Member and you want a chance to play the new Crash Course add-on for Left 4 Dead, send a friend request to the following Gamertag and be online half an hour before (5:30 P.M. Central Time)," says MS.
So unless Microsoft's dishing out early copies to a select few Gold members, we can assume Crash Course will be on Marketplace in the next seven days.
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