Spoiler Alert: DON'T attack bands of slavering dogs. DON'T run into radioactive anomalies. DON'T try and loot dead bodies in the middle of a firefight. And, whatever you do, DOUBLE DON'T attack the military. In fact, as a S.T.A.L.K.E.R., you need to be very, very cautious indeed. Otherwise you will die.
We've just spent the last hour getting hands-on with GSC Game World's long-awaited shooter - for shooter it is, more so than RPG - and we're dusting off our hoodie and returning from the irradiated wasteland of the Chernobyl Zone somewhat the wiser and to bring you our field report.
On initial impressions, S.T.A.L.K.E.R. is reminiscent of Deus Ex but minus the character development. Perhaps this is down the interface, the context-sensitive chat system used to converse with NPCs and the inventory system, but whatever it is, we can't shake the feeling that the Ion Storm classic has influenced the game to a certain extent.
Events kick off in dingy underground room with walls panelled with rusty metal, and a podgy trader is about to hand us our first mission. He gabbles on, telling us about our PDA that contains a map and mission data and referring to us as the "marked one". He reveals we're suffering from amnesia and that for reasons yet to be fully revealed we're rather keen to track down a S.T.A.L.K.E.R. known as Strelok.
But first things first, and our initial mission is to find Nimble, who's in possession of a flash drive containing sensitive data the trader wants to retrieve.
Climbing stairs and walking into sunlight, we get our first proper look at the world of S.T.A.L.K.E.R. Running on our state-of-the-art XWorks X8i-C2D PC, it's an impressive visual feast.
A blue sky with wisps of cloud looms overhead filled with birds, while small bushes sprouting from the ground are blown around by the wind, trees bend in the breeze and dust periodically gusts across the landscape.
A minute spent soaking it all up, we then move off to a nearby camp where a stalker called Wolf not only informs us of Nimble's whereabouts but hands over a pistol and a knife to go with a pair of binoculars already in our possession.
Gun! Hurrah! Unfortunately, it turns out that Nimble's been captured by a group of bandits and so, along with a group of Wolf's cohorts, we've got to go bust Nimble's ass out of jail, so to speak.
Unfortunately, it also turns out that these NPCs don't take kindly to you waving a gun in their face, so I have to lower my pistol to get their sawn-off shotguns out of my face. Whoops. Reputation and relationships with other characters is an important part of the game, you see - build up rep with certain NPCs and you'll benefit from cheaper items when trading and additional info for missions that you otherwise wouldn't receive.
Benefiting from the added fire power of Wolf's buddies, we charge off over a rolling landscape to a dilapidated factory where the bandits are holed up and a firefight ensues, the air filled with shouts of the living, cries of the dying and bullets whipping past our ears.
Pistol out, we pop a couple of banditos but take a few slugs in return and start to bleed copiously, our breath coming out in laboured gasps. 'If you bleed lots, you die' a helpful on-screen pop-up bit of info warns us but handily we stumble across a corpse which offers up bandages and a medical kit when looted.
Apply bandages. Stop bleeding. Use medical kit, get your health back. Incidentally, when you sprint there's a little gauge that displays your stamina capacity. The more weight you carry, the higher this gauge goes and presumably you can become so laden down with gear that running is no longer an option.