Gamers had their fair share of pre-Halloween surprises already: unannounced zombie invasions took place in World of Warcraft, as well as Grand Theft Auto, to name just the biggest names for now. It seems that another AAA title joins the list: this time, the popular first person shooter, Call of Duty 4 is the one infected with zombies. Nazi zombies – which makes us wonder if Treyarch did this or not.

The zombies will invade the COD universe thanks to a new four player co-op mode (which is unlocked only by completion of the single player campaign) will place four players in a central structure, then assail them with wave upon wave of undead national socialists. A kind of a Dawn of the Dead, MMO version. But we dig this.

So, if we are to count the pleasant surprises this year, it would make us believe that we have one of the best Halloweens in gaming. Now I just have to wonder what Christmas events will be brought to us in GTA, for example.