To make up for the shoddy Xbox Live performance over the Christmas and New Year holidays, Microsoft has offered up XBLA title Undertow for free. So we thought we'd check it out and see whether it's a good enough game to satisfy the millions of disgruntled online 360-owners out there.

The key to understanding what Undertow is all about is in the title - an undertow is a strong subsurface flow of water returning seaward from the shore resulting usually from wave action. And that's what it is - some serious underwater wave action.

It rekindles memories of rival XBLA title Geometry Wars: Retro Revolved, and could almost be the same game with a different skin. You move your underwater scuba diver with the left control stick and direct a constant stream of fire with the right, giving you full 360 degree control over everything. The aim of the game is to destroy your opponents and, depending on the game type, gain a pre-set number of resource points by controlling command centres. Simple and addictive stuff.

Depth (see what we did there?) is added by the three playable races (Iron Marine, Nemoidian, or Atlantian), which each have four unique character types that are upgradeable three times during a match. The main considerations here are to do with speed, agility and firepower. You'll find the quicker and more agile unit type has the shortest range and weakest fire. And, as you'd expect, the larger, more powerful rocket-firing mechs are lumbering and clumsy to control. It's up to you to work out which is best for which situation, and which one to invest points in upgrading on any given level.

It can get very hard to see what's going on at times

With a quick-fire 15-level campaign, Undertow will be a short, almost uninspiring experience if you're playing on your lonesome. But it wasn't built for single-player. It was built for multi-player, and as a result has a slew of game options available for getting your underwater freak on with mates or randoms online.

You've got the opportunity to go split-screen with a friend on the same console and play the main campaign coop or some versus action. Or you can go online and play eight vs eight Undertow matches across a number of game types and maps. It's here that you'll dig the most fun out of the game, as long as the lag isn't too bad and you don't lose your connection to the host.

Undertow has an odd, at times perplexing look. It's one of the few XBLA titles to use Epic Games' powerful Unreal Engine, and as such has a quality sheen that most will find impressive. The various unit types, especially the bigger, more powerful ones, certainly look cool, and there's plenty of muffled underwater explosions and slick water effects to please graphics whores. It can sometimes be very difficult to see what's going on, on account of it being a bit dark and the colours used not being bright enough in contrast to the dark blue sea background, but on the whole the game has a quality and gorgeous feel to it.

Does a free copy of Undertow make up for the many lost hours of online gaming experienced over the holidays? The answer will be different for everyone, and dependant on whether you like this sort of game in the first place. Many would have preferred the 800 MS points instead. But if you discount the fact that it's been offered up like some kind of sacrificial lamb by Microsoft, it stands on its own as a solid, fun and at times entrancing shooter that stands head and shoulders above most titles on the service in the graphics department. It might not have the immediate addictive qualities of other similar games, like Geometry Wars: Retro Evolved, but it's miles better than some of the tripe on XBLA. Be smart and grab it now while it's free.

Undertow will be free to download until 07:59 GMT Monday 28 January 2008.