The post-apocalyptic world of Metro: Last Light is dark, gritty, almost oppressively atmospheric. Humanity’s split into factions; radiation-spawned monsters roam the surface, and to walk above-ground, you need to wear an air filter. Bullets are the rarest of commodities, doubling as both death-dealers and vital currency.

Previous Last Light demos (at the last two E3 shows) have touched heavily on this sequel’s story, which follows Metro 2033 protagonist Artyom in the aftermath of that game’s conflict with the monstrous Dark Ones. These sneak peeks showed him infiltrating a meeting of the Nazi-ish Fourth Reich party, battling mutated beasties on the journey to another station, and recalling the awful day nuclear devastation struck in 2010. Intense stuff to be sure — and a decided contrast with our recent demo, which focused more on Last Light’s gameplay mechanics and small details.

Our new glimpse began at a spot early in the game, with Artyom trying to free a comrade imprisoned near a subterranean power facility. Wandering Fourth Reich guards presented a dilemma: try to skirt around them unnoticed, or come in firing? Our demo guide took both approaches — avoiding one group by descending into sewers and coming up on the other side of them, while dispatching other sentries in a variety of ways. Because bullets are so precious, you can sneak up on foes and slice their throat from behind, or simply let them live when they beg for their life. Or you can ditch frugality altogether and cut loose with improvised weapons like a pneumatic rifle and machinegun; look closely as you’re firing, and you’ll actually see ball bearings loading and expelled shell casings colliding.

Light sources played a considerable role in this rather dark area. As he wandered about, our demo guide shot or unscrewed numerous lightbulbs to better mask himself in shadow. In Last Light’s hard-scrabble future, he explained, guards wouldn’t flinch at a bulb suddenly going out; they’d more likely attribute the failure to old technology finally reaching its breaking point. Of course, in another nice touch, you can also snipe a guard’s headlamp — an outage that’ll prove just a bit more suspicious...

The demo’s second portion focused more on your social interactions in the game. Passing through a small village in underground Venice, we saw people going about their business: two men chatting at a table, a woman gutting a mutated fish. Artyom’s come here in search of “a human quarry with info you desperately need” — a quest that takes him behind closed doors, to an area brazenly labeled “Sex Shop,” complete with chattering gawkers and a female pole-dancer. At a nearby armory, we watched our hero trade his homemade bullets for more valuable military rounds. In another example of Last Light’s intricacies, your weapons are extremely customizable, letting you add an infrared sight, silencer, heatsink (reduces overheating), stock (lessens recoil), and other parts.

For the last part of our demo, we warped to an outdoor marsh area, at a point midway through the game. Artyom and his buddy are trying to get a floating ferry operational, so they can ride it to a nearby church. Here on the irradiated surface, you can expect the unexpected: slimy creatures leap at you from the water, and in a sewer pipe, a reptile-like critter slithers by as you hurriedly loot filters and bullets from a rotting corpse.

Adding to the game’s ambiance is the absence of any obvious HUD; the level design simply gives you a general sense of where you have to go. Before you can get on the ferry, you have to fend off a claw-waving amphibian accompanied by smaller, acid-spitting mutants. It’s a tense battle in a tense environment, and by the end of it, we — like Artyom — were ready to leave this hectic place for something a little more calm. Whatever comes next, we know it’ll be interesting…