Team based Versus mode, supporting up to eight players, is back and better than ever. The new infected add a needed jolt to this mode of play as it offers more variety rather than repeatedly being stuck with the Hunter. Really – who doesn't want to play as a Jockey? Survival mode, which is a holdover from the original, tasks the survivors with lasting as long as they can from a never ending stream of infected.

New to the sequel is Realism mode, which is exactly what it sounds like – bullets really hurt and so do zombies. You also cannot see ghost outlines of teammates so staying together is even more vital to survival. Note: If you're good enough at this game to pull off beating all the campaigns on expert with realism turned on then I'd like to know your address – I'm coming over if there's a zombie outbreak. Rounding out the features is Scavenge mode where the survivors scramble to try and collect cans of gasoline.

It needs to be stressed that if you thought Left 4 Dead was too challenging then the sequel might cause you to lose hair from both stress and manual ripping. This is a hard game – even on normal difficulty. It’s almost like Valve said to its fans, “Ok…so you thought Left 4 Dead was too easy, eh? Well try this on for size!”

To counter the ramped up difficulty you are given new melee weapons which are brutally efficient – like the katana and the chainsaw, both of which go through zombie flesh like, well, much like a chainsaw goes through flesh. You also get a lot more firepower including an Ak-47 and a military Sniper Rifle among many others. You can now grab a defibrillator unit (in lieu of a health pack) to bring back dead teammates (and they will die, trust me) and you can shoot up with an adrenaline shot in order to run faster when you need to make a daring and necessary escape or are asked to run through a zombie horde to turn off a siren.

The increased difficulty doesn’t change the fact that this is a better designed game from top to bottom: the finales require you to do more than huddle up and shoot zombies as they charge you; the set pieces are more interesting, and the level design requires more thought than just running down the next obvious open street.

Left 4 Dead 2 is the Empire Strikes Back of zombie games. The momentum has clearly swung in favor of the bad guys. But also much like Empire, this is clearly the best of the bunch and is a required purchase for fans of the genre. Just don’t expect a walk in Zombie Park.

Questions or comments? We'd love to hear from you .