In the jumble sale that is the recently released Community Games channel on Xbox LIVE, it's hard to see what's good and what's, well, clearly been coded in a few afternoons in a bedroom. You can tell what's popular, but that's got as much to do with the effort put into the cover art as it does the quality of the game. So, to save you spending all your MS Points on a wild goose chase for quality titles, we thought we'd review one of the best that's currently available. Despite the fact that Biology Battle, from Novaleaf Game Studios, is quite clearly very similar to the superb Geometry Wars and the even more superb sequel (and costs as much as the latter), it's still worth a look if you're keen to delve into the user created chaos.

If you haven't worked it out yet, Biology Battle is a twin stick overhead shooter, with the left stick controlling movement and the right handling firing all around your craft. At first, for us, everything felt a tad twitchy, perhaps because we were so used to the movement of Geometry Wars, but it didn't take long to feel at one with the ship as we zipped about the enclosed play area. Instead of shapes you're battling bacteria and viruses, which move around in a hectic manner, as if they were in fact the shapes from Geometry Wars. You even pick up power-ups that perform similar actions as seen in Geometry Wars, such as lightning that essentially clears the screen.

What makes Biology Battle a worthy game in its own right and something that in the end feels rather different to Geometry Wars is the way the scoring works. The game is split into two phases: Life and Death. During the Life phase your multiplier constantly increases, meaning it pays to simply stay alive as long as you can. Shooting enemies and scoring points helps, but survival is key. After some initial enemy shooting a number of nuclei will appear, and these hold the key to the Death phase. Once all the nuclei have been defeated you'll acquire a token which will let you switch over from Life to Death, where your multiplier is increased x10. Here the multiplier is locked and it's then a battle to score as many points as you can with the lives you have remaining.

This split game design presents a number of interesting choices. It obviously pays to stay in the Life phase for as long as possible, increasing your multiplier, but the real points are to be had the Death Phase, so you don't want to leave yourself short on lives by wasting them all trying to survive in the Life phase. Power-ups and how you use them come into play too. Stick around in the Life phase for long enough and you'll eventually add a push and black hole ability to your arsenal, although the black hole is only good for clearing enemies as you don't earn any points for those kills. So, it's effectively something to aid survival, and therefore not much use during the Death phase, where killing and earning points is key.

During your first runs you'll likely be drawn to pick-ups like a child to candy, but most of these are temporary assists and simply aren't needed when facing the relatively easy opening enemies. Power-ups remain in play if you ignore them, so it's often best to store them up, giving you some much needed extra fire-power and shield safety when it's really needed.

There's a solid selection of multiplayer modes

After a few hours the game starts to click and you'll have figured out a few tactics in order to maximise your score for your level of skill, but as you improve you can rethink how many lives you're going to risk in the Life phase as you know you're going to survive for longer in the Death phase simply because you're better at taking out enemies. The one real problem the game has, which is what made this year's Geometry Wars 2 so brilliant, is the lack of friend leaderboards. There is a local and global leaderboard (which shows the top 100 players), but you can't see what your friends' best scores are.

Multiplayer is another area in which Geometry Wars 2 has the edge. There's no shortage of modes on offer in Biology Battle, including a kill nothing, survive as long as you can while giant worms move across the screen mode, and a few that rekindle memories of the Tron bikes, but we didn't get the same buzz and desire to keep playing as we did with Bizarre's game. The multiplayer modes in Biology Battle support up to four players, but we preferred the high-score focussed single-player mode (which incidentally can be played with friends too).

There's no doubt that Biology Battle is an extremely polished title. It lacks some refinement in the menu designs, but in-game it's easily good enough to pass as a full Xbox LIVE Arcade title. The problem the game and its developer has is that Geometry Wars can be bought for 400 MS Points and the sequel can be had for 800 MS Points - the same price as Biology Battle. While we can't recommend you buy this over Bizarre's stunning shooter, if you're after an extremely competent twin stick shooter and want to support the XNA service, you won't be disappointed with Biology Battle.