Back in the day, playing cooperatively through a game was a fairly new and rated thing. We had Mario for the evenings and Double Dragon for the weekends – all was peachy. Then, somewhere along the way we lost focus a bit and decided that forging friendships was actually quite a pain in the arse and so we were more interested in how the game looked and how it told its story. Some time passed, and then like a whisper on the wind, cooperative games were being called out for. Sure, we didn't have friends, we had random people over a network that we'd never met before that we could call friends because they didn't piss us off as much as some of the other newbies we'd had the unfortunate experience of running in to.

A problem struck when game developers were asked to not only introduce cooperative, but make the game look pretty, have a decent and engrossing storyline, not crash, be fun to play and if you took it home to meet the parents – they'd heartily approve. Of course, this was all a bit much. So now we're left with games that either focus in one direction or put their mad scientist coats on during a storm and hope if they crank up the juice they can put lots of bits together – and as we all know Dr. F, 9 times out of 10 they create a monster.

While hashing a couple of extra features in, Killing Floor largely focuses on the former I'm happy to say. A game that's effectively a polished mod developed by the Tripwire Interactive crew who previously released Red Orchestra, which was generally well received across the board. It focuses very much on cooperation between team-mates to the point that if you don't work together, you're going to die horribly. The idea, in the basics, is to survive against waves of monsters that increase in difficulty. There are 7 waves per map, of which there are 5 to cycle through. Each player can choose how they look and what they're currently specialised in through a perks system. Each perk offers benefits to certain attributes and each perk will level up based on performing actions associated with them.

After each wave has been dealt with you'll get the opportunity to buy and sell weapons with a randomly located Cockney trader. If you think Counter-Strike at this point, it's effectively the same principle. You can buy ammo, armour, grenades and primary, secondary, special and melee weapons. These can include dual-wielding pistols, to chainsaws, flamethrowers and crossbows – it's really down to picking your flavour given how each member of a team realistically has to follow roles. The added interest to this zombie-monsterfest is the ability to weld doors shut using, of all things, a welder. Additionally, the ability to heal is always available through a recharging syringe. However, healing your team-mates has been made more effective than healing yourself. So, with these couple of points in mind you can start to see how the team might be made up. Having a medic and support keeping a door welded shut and people healthy while you have a couple of ranged and a couple of assault lobbing grenades and generally making things dead and/or crispy through a bottleneck you've created into the room. Of course, should any part of that system fall down or your team gets overwhelmed, things will probably go badly.

Killing Floor allows 6 players per game, and seeing as it's a page out of Left 4 Dead's survival mode but with more players and different options, it's certainly something worth a look in. You also have the added bonus that should die during a round you'll get to respawn after the wave has finished, albeit with less cash, which at least gives you another chance to die again.

The game's still on the buggy side until the guys get around to patching it, but I would argue that none of the bugs fundamental break the game. If anything I'd say that perhaps the downside appears to be the difficulty scaling. Matt and I had a good go at taking on the hordes but around wave 5-6 you're dead in the water as some of the boss-like monsters are introduced and require more fire-power than you're going to get with just 2 players and no bots (although what freakin' good are they anyway?) - particularly one “The Patriarch” who's just going to seriously stomp on you.

At £15 you can't really complain at the lack of maps at this stage, more can always be added later, and you do spend a good length of time (if you're any good) on each map that have at least been made to look pretty good. Sure, for something on the Unreal engine it doesn't blow you away, but it does it's job and in the right set up it's a laugh... although I seem to be laughing more at the terrible voice-overs more than anything. Not that this is a note to leave the review on mind you. No, I'd say it's definitely worth buying if zombie-horror-survival-cooperative-shooters are your thing – or if you think they should be.