Depending on which group of scientists you choose to believe, global warming is either a natural cycle caused by conditions beyond our control, or a man-made, time-lapsed suicide. Away from the hot air of hype and headlines though, it seems we've forgotten about all the other wonderful ways we might wipe ourselves off the face of the planet.

The citizens of Cyberblood's Haven have, in contrast, forgotten all about global warming: recycling tends to take a back seat when the Last War has already turned your city into a wasteland of rubble and death. As if that wasn't bad enough, a mysterious and deadly plague is spreading throughout the metropolis, affecting every living being except one.

Which, would you believe it, is where you come in. You are Marshal Zek, cyborg guardian to the people of Haven. Under the guidance of settlement leader Helen, your task is to find the source of the plague, eliminate the roving 'gangers', and finally uncover your own origins. Oh, and bring peace to the city.

All in a day's work for a cybernetically-enhanced hero. And an enjoyable if somewhat unusual time out of the office it is, too.

You begin your adventure at the bottom of a well, charged with finding the source of the plague. Controlling Zek via a combination of thumbstick and keypad, you must work your way through the maze-like level, eliminating a small group of hostile crabs in the process. Luckily Zek has a gun-arm implant, which can be activated by pressing '5' on the keypad. As long as your gun is active, it'll automatically fire at any target that comes into range.

Zek also has a number of handy modules you can swap between using the * key. To begin with, you only have the radar and stun modules, but by collecting Zircon gems – the local currency – you can afford to buy better upgrades from the people of Haven.

Activating a module uses energy, shown as a blue bar beneath your health bar. This energy regenerates pretty quickly, though, so you can use your modules liberally.

Gameplay continues to be straightforward: navigate your way through each level in turn, making sure your gun module is always active whenever you meet an enemy. Scattered throughout some levels are explosive barrels and these can be detonated by pressing '5' when you have them targeted, causing an explosion that affects the surrounding area and inflicts damage on anything caught in the blast.

Aside from these barrels, the only real interaction you have with Zek during a fight is moving and activating modules. As mentioned, shooting monsters and gangers is handled automatically as long as your gun is active, which serves to distance you slightly from your avatar.

There are numerous modules and upgrades available from various vendors in town, each adding a different tactical option to your arsenal, but one flaw with the game is that aside from the health and energy upgrades, the only module you'll ever really need is given to you free upon completion of the first level. This Bio-module converts energy into health, enabling for hit-and-run tactics against the more difficult enemies later in the game, due to their slower movement speed.

On a positive note, CyberBlood's strongest feature is its music. Developer Rovio tends to invest a lot of time into the presentation of its games, and this is no exception. Techno-pop meets grungy guitar crunches, providing a soundtrack in keeping with the post-apocalyptic theme of the gameworld. The levels are nicely detailed, too, with toxic waste pipes and burning wells scattered throughout the rubble and decay.

There aren't quite enough of those levels, mind – CyberBlood is a bit too small in scale. More and different environments would have added some welcome diversity. Furthermore, the lack of interaction with your weapon is strange; you become used to it after a while, but it never quite feels completely right, as if you're missing a vital link between you and Zek.

Despite these minor flaws, CyberBlood is overall a fun game, with an absorbing plot that gives it a depth lacking from other action games. Don't expect it to keep you playing until your fingers bleed, however.