After you’ve beaten what could turn out to be one of the best World War II shooters on the market, Call of Duty: World at War, your job won’t be done quite yet--you’ll still have to take up arms against hordes of the undead.

According to GametrailersTV, completion of the campaign mode will unlock a new mode of gameplay called the Nazi Zombie Apocalypse. This new gem is one of the most striking additions to our knowledge of the upcoming game, and it may well be the most interesting.

Allowing up to four players onscreen to cooperatively combat the Nazi zombie menace, the unlockable mode will call for some major Night of the Living Dead-esque survival strategies. As an endless horde of the undead approaches, players will have to take such measures as sealing windows, watching in every direction, and reviving teammates as necessary in order to earn in-game money. The money will be used to obtain new tools to aid in fighting the good fight or for more obstacles to keep those pesky zombies at bay.

Zombies, zombies, everywhere! With games such as Left 4 Dead being released, and GTA IV catering to the shuffling menace, it’s a great year if you’re a zombie fan. Could the addition of this co-op mode make the latest Call of Duty a rival to L4D’s multiplayer zombie crown? We’ll keep you posted as more updates on this ingenious mode arise. Until then take a look at our initial impressions of Call of Duty: World at War and how it stacks up against Call of Duty 4.