Today Valve announced that their upcoming Left 4 Dead 2 will have a fourth, entirely new game mode.

This mode is called “Scavenge,” and it pits players against both the clock and the Infected.

In Scavenge mode, Survivors are given a set amount of time to collect gas cans to refuel generators located in each map. The gas cans are located around the map, and they add time to the clock when used to fill the generator.

The Infected have to stop the Survivors from refilling the generator, and can do that by destroying the gas cans, killing the Survivors, or running down the clock. Infected can choose to play as any of the old Infected characters as well as the new Spitter, Jockey and Charger.

The four-man teams will have the opportunity to play as both Infected and Survivors in each round, and the team with the most gas cans wins.

Look for the new Scavenge  game mode when L4D2 drops November 17th.