So, here very recently, Valve thought it'd be a great idea to add a co-operative game mode to their Free-to-Play giant, Team Fortress 2, known as Mann vs Machine. You know, survive against waves of foes and purchase upgrades via cash earned from killing them. We've seen it all before, so what can Valve possibly bring to the table that others haven't?

Well, Valve has class. Rather, Team Fortress 2 has classes. Nine of them, you know? This alone sets the game apart from the rest of the pack. With unique upgrades for all of the classes available for purchase, as well as the ability to use unlocked equipment from your time playing the game before this, there's room for a lot of variety in your team and how the matches can be played.

Engineers can buff their turrets and amount of resources they can carry to maintain them, or they can upgrade a weapon so that they can be more offensive and leave their turrets to their own devices. Buff up your Scout with high damage resistances and you can barrel into enemy lines to decimate robot opposition, or you can boost his speed to get him in and out of the action quickly for guerrilla tactics, which are surprisingly effective against the rather obtuse AI in this mode (more on that later). There are a number of ways things can happen just by mixing up classes and their upgrades. When you add in the custom weaponry you can take into battle as well as new canteen power-ups, which can be used to grant temporary boosts such as invulnerability or an instant ammo refill, the diversity is far from what you find in other co-op shooters.

Team Fortress 2's classes also make up the foes you'll be facing off against in Mann vs Machine. Pyro bots come by the swarm, threatening to torch any players foolish enough to get too close to them, while Heavies throw up their fisticuffs, ready to box any player clear across the map (or to death, too, you know) should they cross their path. These bots are plentiful, and they're trying to carry a bomb into your base, which you clearly have to prevent. If they succeed, Mann Co. will be ruined, and then how will you ever get those snazzy hats?

Stopping the bots from carrying the bomb into your base is harder than it sounds. Kill one who holds it, and they drop it, only for it to be picked up by another heartless, metallic comrade. Don't kill the one holding the bomb for a while, and they'll slowly build up bonuses, starting with higher defense, then health regeneration, and if you wait too long, they'll even start landing critical hits with every shot.

However adamant they are with running this bomb into your base, however, they aren't exactly the brightest crayons in the box when it comes to pathfinding. Sure, this is intentional on Valve's part for sure, as they clearly denote the path the bots will take with the bomb before you even start a wave, but the fact that there's really no deviation whatsoever makes them a bit more prone to stupidity than they should be, and in my time playing the mode, there were even a couple of moments where they got stuck, and the bomb simply respawns at the beginning of the map again. Set up a turret in the right spot, and you're guaranteed they'll pour right into the line of fire. Guerrilla tactics are very viable, too, with running and gunning being an excellent strategy for fast classes just as it should be.

Even though they have clearly basic AI when carrying the bomb, it is nice to know that certain bots, such as the boxing Heavies, Demoknights (Demomen with swords), Sentry Busters (robots that target Enngineer buildings and self-destruct on them) and Spy bots deviate from the given path in an attempt to shake things up, and this often is all it takes to make the game become savagely difficult.

Now, despite the straightforward AI in this mode, and the seemingly easy objective, this mode is unforgiving and difficult. Without a fully populated team of six, Mann vs. Machine might just turn into Man vs. Machine as you hurl your computer out the window in frustration. With no handicaps set for an incomplete roster, it can be very frustrating to lose a comrade in the middle of a run, and nigh impossible with any less than five players to even complete a single wave on some of the harder maps. With six players, it is possible to beat all of the maps, of course, and with a team of skilled players, can even be 'easy' on some of the maps, but more often than not, it still proves more difficult than most players would likely prefer.

Regardless of the extreme difficulty, this mode is still very fun, and any players who were fans of Team Fortress 2 before will surely enjoy this new addition and find themselves putting in a lot of time. Community servers will likely be the most popular way to play, but special "Mann Up" servers, which require tickets to enter (that cost real money) do offer the promise of great in-game loot when played, with the best rewards accompanying success, of course.

If you like first-person shooters and haven't tried Team Fortress 2, there's little reason not to give it a shot unless your computer simply can't handle the Source engine. If you haven't played TF2 in a while, maybe Mann vs. Machine is just what you need to get back into it. I recommend that everyone who has enjoyed the game before to try this out at the very least, and anyone who hasn't tried the game at ll I advise try it, too.