It has only one mode and purpose, but many will be surprised how many hours will be spent just killing every thing in sight. If someone doesn't enjoy this game I feel sorry for them.
Even if it's a knock-off from Unreal Tour. Killing Floor brings the zombie killing coop I've been aching to have. Also with upgrade-able perks and destructive weapons of all sorts, the slaughter of undead specimens will bring you back wanting to play again.
£15 for this is a bargain and shouldn't be passed up with an fun game like this. Definitely a must buy.