The new game type that will ship with Left 4 Dead 2 has been announced. In it the survivors have to collect gas cans and pour them into a generator. They must do this while battling the clock and the infected, so it sounds like a combination of survival and versus. Every time you add fuel to the generator, you get a point and add time to the clock; whichever of the two teams gets the most points wins. Meanwhile the infected need to stop the survivors either by attacking them, destroying the gas cans, or running the clock down.