Destroyed beauty is how the game's designer Cliffy B describes its look and most of whom who have seen it would have to agree. The dusty, deserted, rubble-strewn architecture invokes an image of a once-mighty empire; now battered and beaten, decrepit and in decay. Which is of course the aim. Years of in-fighting have ill-prepared the warring factions of the once-glorious Sera for the threat from within – the invasion by the subterranean Locust Horde. Where they come from and how they got there is uncertain but what is known is that Sera's defences are in tatters, weakened by their own greed and squabbles for Imulsion, the planet's prime energy source. All who are able to fight do so under the command of the Coalition of Ordered Governments. Yet a few years after Emergence Day, with billions dead and no stopping the Horde's brutal and relentless attack, humanity teeters on the brink of extinction. It is these overwhelming odds which earns Marcus Fenix a reprieve. Previously incarcerated for insubordination, the former soldier is freed from one prison but delivered to another – straight back into the service of the COG. Fight or die, preferably in that order if given a choice, but at least with a chance of redemption – from prisoner to saviour in the game's five acts.

A prison is also how this title could be described if one was being particularly harsh. Very much on-rails for the majority of the game and with little room for manoeuvre or deviation from the given path it initially appears restrictive. But appearances can be deceiving as free-form sandbox play is not its aim. No, instead it has been designed around the concepts of cover and shoot, not run and gun and thus the locations are necessarily enclosed, confined and restricted in order to encompass a sense of urgency and panic, gunfire ringing all around. Taking full advantage of the detailed environment is as essential as pulling the left trigger to aim and the right trigger to fire and applying typical first-person shooter mentalities will quickly lead to your Crimson Omen filling with blood and a swift demise. No longer will circle strafing and bunny hopping provide adequate protection and earn you kills. In fact, that stalwart of videogaming, the jump button, has been deemed surplus to requirements. Surely more of a nod to gaming's platform origins rather than a modern necessity in the battlefield. Thus jumping has been retired - removed, updated and replaced with the more realistic, down to earth and downright essential dive-into-cover which despite initially feeling alien will soon make you wonder where it's been all this time.

The over-the-shoulder third-person viewpoint is another break from the norm and combined with the shakes and wobbles of the camera serves to amplify the urgency of combat. The Roadie Run takes you another step towards becoming immersed in the game, providing a panic all of its own yet still daring you to run from cover to cover whilst Locust bullets trail in your wake. The controls in general are succinctly mapped, with the A button taking care of most context-sensitive actions. In this case holding down A causes Marcus to crouch and run with the perspective suitably narrowing as he darts forward until reaching a barricade to cover behind.

That's cover, not cower mind as this soldier can easily give as good as he gets. Aiming and firing will expose you for a critical few seconds, whilst blind firing keeps you firmly in cover but is nowhere near as accurate. Weapons on offer include the usual fare of machine guns, pistols, shotguns and sniper rifles, with grenades rounding out the core ordnance. The standard COG machine gun, the Lancer, also comes equipped with a chainsaw for close combat melees should you run out of bullets at an inopportune moment or simply want to go for the gruesome, extravagant kill. For the truly sadistic though there is the Hammer of Dawn, a laser-guided weapon utilising overhead satellite fire. Despite taking a few seconds to home in, there is a kind of perverted pleasure to be gleaned from targeting an unsuspecting enemy and watching them be blasted to smithereens by an overhead particle-beam. It is a shame then that for the majority of the game this weapon is confined to certain set-pieces with some of the larger enemies being solely susceptible to this device.

Large or small though the Locust Horde does not hold back, shooting to kill with brutal efficiency. This is especially so on the higher difficulty levels when breaking cover for even a few seconds can prove fatal. To even the odds fellow COG soldiers fight on your side, initially Delta squad and later Alpha squad. Unless in co-op mode these soldiers are controlled by their own AI and act on their own initiative. And act they do which is mostly a blessing but on the rare occasion can be a curse. It is a given that their primary aim is to eliminate the enemy yet occasionally they strike whilst you are still orienting to your location, wiping out most of the Locust in the process or crossing your line of fire. At other times their gung-ho nature will see them taken down, falling by the wayside and leaving you to clean up the mess. No-one really dies though as health will be restored upon completing the set-piece. Should you wish you can restore their health sooner by getting close and reviving them. Make no mistake though, both sets of AI are well implemented with you often feeling like the hunted and not the hunter.

Despite being quick to get through on the single-player front the game is sumptuous and demands to be replayed on a higher difficulty setting. Beyond that it is reassuring to know that just as much thought has been given to the multiplayer side of things as the rest of the game. In fact, GoW has been designed as much around Xbox Live as it has around the Xbox 360. A full complement of maps and modes are provided, with no doubt more appearing for download over the next few months and as great as the multiplayer games are, it is in co-op play where things shine. Seemingly in vogue at the moment, the co-op mode allows the whole game to be played through with a friend taking the role of Dominic Santiago for assistance, via either split-screen, system link, or Xbox Live. At certain points in single-player a fork in the road is presented, giving the choice of which path to take. In co-op mode both players can take different paths, providing covering fire from different vantage points and tackling the level from a different angle.

As good as things are though nothing is perfect. Other than cover, there is no real interactivity with the environments and whilst certain furniture can be destroyed, some cannot. And those that do fall apart do so in a not entirely believable way. Some will also nitpick at the washed-out, monotone look whilst for others the short playing time will hit a nerve. Neither of these are critical yet they still deserve to be mentioned. As does the fact that saving a co-op mode checkpoint will overwrite your single-player checkpoint and vice versa. Why two save games could not be provided is as mystifying as the origins of the Locust Horde and will probably not be resolved until at least the inevitable sequel and, if the rumours of a trilogy are true, that sequel's sequel.

Despite these minor hiccups Gears of War is as much a reason to own a 360 as Oblivion was and more besides. In fact, it is just as much a reason to subscribe to Xbox Live as Live Arcade. Appropriately billed by some as a third-person tactical action/horror shooter it is frighteningly good. Although what's really scary is to think what things will look like with a few more years' development time and the know-how to push the hardware even further. As the end-of-game Locust narrator states, humans were destined to destroy. Although sometimes they can create glorious worlds too.