E3: S.T.A.L.K.E.R. Clear Sky

Having spent over six years getting Stalker into shops, GSC could have kicked back for a bit. They deserved the chance to, for want of a better phrase, zone out. At least for a bit. Instead they've come back with a game that's just as big. It's not even an expansion - it's a full-blown prequel. And it won't take them six years this time, according to Oleg Yavorsky and Valentine Yeltyshev, demoing the game at E3, neither of whom looks particularly worn out despite the developmental trek and the long flight from Ukraine. Perhaps, for them, the journey's the worthier part. (Bound to be more fun than talking to me, either way).

Clear Sky, as this one's called, plants you back in the irradiated boots of Strelok, as he embarks on one of his earlier visits to the Zone of alienation - the 30km exclusion zone surrounding Chernobyl's nuclear reactor. Shadow of Chernobyl had been built around his third. As usual, wonky things are afoot (they had a bit of an accident there, apparently), and a group of stalkers has made it to the power plant itself, their actions resulting in "an immense blowout" that destabilises the Zone significantly. There are no more safe bits, and there are new areas - Red Forest, Limansk and Pripyat's underground among them - while the effects have thrown up lots of our old friends the anomalies.

That's about all we're told about that, with Yavorsky and Yeltyshev preferring to showcase the DirectX 9 renderer (the game does support DX10, but it's too much of a work in progress to be brought over at this point) and the improved animations, character models and environments it's supporting, along with a few scripted situations involving a band of your fellow stalkers, as we slap our fingers on the keyboard and get back in the Zone.

Combat should be more dynamic than before, says GSC.

As we trundle into a busted up hospital that's subsiding as much as it's crumbling, our guide points out the heavy use of parallax mapping to give volume to brick surfaces, rusting metal and cracking tiles (the DX10 version will do superior displacement mapping instead), and says the game's done away with light-maps completely, so everything's dynamic. As we stare into a large hall with most of the roof blown out and balconies running around the walls about halfway up, gunfire from the opposing forces camped on either side pings off a rusting lamp, which swings back and forth from its lengthy cable fixture in response. The light from the muzzle flares strobe the enclosed upper levels for the duration of each clip, while the punctures in the ivy-clad rafters above sprinkle shadows across the surface of the dying metal as it swings. It all contributes to the atmosphere - a facet of Stalker we liked so much that we put it in italics about 18 times in our review of the first one.

Despite all this, the game's system requirements will be consistent with Shadow of Chernobyl, according to its developers. Which means that - yes! - you'll be fine to enjoy things like the increased use of physics, with wheelchairs tipping off balconies in confusion, boxes shattering under fire, and destructible environmental elements. And yes, your PC will continue to handle the scripted events, like the bit where your factional pals plant explosives at the foot of a wall and blow a hole in it to continue their progress, darting through the gap in swirls of plaster dust that shouldn't cost you any more frames than you ever lost anyway. That good old PC of yours, eh?

The hospital from our demo, looking pretty good. If it were NHS, anyway.

Meanwhile, a new animation engine couples itself to handsome new character models. Peering at the new stalker model (hooded by a top patterned as a cross between desert camo and a freeze-pop, by the looks of it, with a weathered battle vest, ribbed shoulder pads and insignia of birds fleeing a sun over water on either bicep), you can really appreciate the textural detail - it looks just like stitched cloth - but now there are a broader range of movements to match the fidelity and normal-mapped volume of the model, including a range of blind-fire attacks from cover, crouched running and lots of surprisingly conservative rag-doll deaths (involving, in this case, our God mode and Strelok's grenade launcher).

Yeltyshev makes promises of as much if not more freedom than we experienced in Shadow of Chernobyl, but in the demo's case we're funnelled through scripted encounters, raging as our assault rifle jams mid firefight and a helicopter attacks our faction in the hospital (its health-bar: no match for our invincibility), before we're pinned down in a bumpy second room by a machine-gunner and forced to fight off a trickle of enemies who descend on us for the two minutes that it takes our stalker pals to force their way through and drop a grenade on the gunner to enable our progress.

The leaning towers of teaser.

As well as more of these factions, Clear Sky also promises the chance to join any one we like, rather than just two. They're all fighting over the Zone, trying to take hold of different areas, including resource points (where they then hunt down artefacts to build up their wealth and assert themselves that way) and technology points (useful for access to better weapons and equipment), and if you ally yourself to any of them, you can conceivably lead them to victory, or at least improve your chances. They'll be smarter in battle, too, and go about their business without you if you shun their services - the A-life system giving them the freedom to engage one another for profit and glory, even if you're just a bystander.

After our demo having been limited to just an action sequence and techy banter, we're told end to expect a more substantial presence for GSC Game World at Leipzig's Game Convention, which we'll also be reporting from in late August. Yeltyshev is coy about discussing who will publish the game, simply saying that negotiations are going on behind the scenes, but he repeats the first-quarter 2008 release date, and sends us on our way with a disc full of fancy new screenshots, giving us about a dozen total. We thought we'd mention it here because the poor chaps were being forced to step away to their laptop every few minutes to burn a few more. Everything's as cheerfully warped and rugged as ever, then. Zone out.