Undertow is a side-scrolling shooter in which you must capture five checkpoints littered around the murky underworld in order to stave off attack by numerous types of bad guys. You take on the guise of Iron Marines, Nemodians (followers of Nemo of course!) and Atlantians. Your motivation for all this shooting is to survive a new water world that has been created after we all threw our fridges into the sea and the world warmed up thus melting the polar caps and drowning the planet. Ok, the 'we' is an alien race and the 'threw our fridges into the sea' is 'devastating attack' but you get the picture. It all sounds rather silly, and in fact it is rather, but sometimes I like a bit of silliness and this is one of those occasions.
You can choose between four types of craft that vary in speed, agility and firepower. Sometimes you might just need some light infantry to scuttle across the map to the unmanned checkpoint, stand there for a few seconds, wait until it goes blue and then it's yours. However the enemy will soon suss you out so it's time to bring the big boys in. But they are slow and don't have a very high rate of fire. So if the enemy are numerous then maybe you should choose something in between. It's not the hardest concept in the world but it's highly addictive.
Similar to Geometry Wars, it's a left-stick move, right-stick shoot scenario with the addition of a boost button (handy for quickly wrangling yourself free from a surprise three-pronged attack) and button for dropping depth charges (handy for giving the bad guys something to think about just before you make your aforementioned hasty retreat). The ease of which you can pick up and play Undertow works to the game's advantage for the most part as it makes it perfect for a quick fifteen minutes' gaming whilst the missus is putting her face on.
Where the ease of use works against the game, however - and in fact this problem undermines the whole experience for me - is that the Campaign part of the game is over so quickly. The three areas with five sub-levels are sadly a fleeting experience and this is only emphasised by the fact that Chair Entertainment have seen fit to give you infinite lives, so the only way you can die is to lose all five checkpoints at once, which won't happen too often. Although the level design is excellent - offering multiple routes from checkpoint to checkpoint and thus opening the game up tactically instead of a pure blast-'em-up - there just simply isn't enough of them to warrant the 800 points being charged. However, if multiplayer is your thing then this is the game for you.
Supporting up to 16 players at any one time this game is perfect for getting a few friends, and soon friends of friends etc., together and battling it out over the digital network megaverse that is XBL. As mentioned earlier, for such a small (50MB) and simple game the level design is perfect for multiple entry points and the tide can turn in your favour several times throughout a match making them intense and giving you, the gamer, that gritted-teeth grin on your face that all games should do.
Graphically for something so diminutive in file size it's highly stylised, and the levels all have their own unique look and feel. Your different vessels each have bright and satisfactory looking firepower and when you've got a dozen ships on the screen at once, each trying to blow the other into kingdom come, it's a sight to behold. So much phosphorous goodness! All this runs without a frame-rate drop in sight and the tearing brigade can get off their picket lines as they won't find anything to rally about this week. Unfortunately when the action gets heated and you've chosen the nippiest of your underwater boats it becomes rather hard to see exactly where you are at times but this only really adds to the complete chaos unfolding in front of you. It's a minor niggle but worth a mention.
The Ebenezer Scrooge in me still feels that 800 points is a rather large sum for a two to three hour single-player experience. And being a cynical old goat multiplayer is only really fun when you're playing with friends, and if everyone on your Friends List is currently trawling through Mass Effect then you're faced with a trip into random city and those 'unknowns' on Xbox Live really do scare me quite frankly. Anyway, back to the silliness. Undertow is a fun, no-brainer and is a welcome addition to Xbox Live. Make sure you convince a couple of mates to fork out for it as well and you'll have a blast.