Not your usual sci-fi/horror shooter, has a much slower and methodical pace.
ATMOSPHERE -- To those saying that this game should have gore - BLOOD DOES NOT FLOW WHEN IT'S FROZEN! All creatures you fight are frost-spawned mythical/fairytaliy creatures, which seem more the embodiments of human vices, rather than flesh and blood, with an eerie reminder of what the story is about (like the creature with a tiny prison cell in his skull, or the one with a siren-like scream and PPSh-41s strapped to his arms, I guess to remind the player of the imprisoned minds of the ship's crew, held behind a veil of Soviet regieme). I think this game would lose much in the atmosphere had it had gore in it. The frozen nuclear-powered ice breaker atmosphere has been created with great detail and sounds, effects and enemies are creepy. A while after playing it through the first time, I remembered it not being particularly scary, but I changed my mind quite fast once I started playing it the second time. I was born in USSR, and this game brings about a lot of nostalgic memories of childhood, wandering around derelict buildings in Ukrainian country side (so does STALKER, by the way). Human characters have captured the Soviet mentality pretty well, which will be a treat to anyone knowing or willing to learn about those times.
GAMEPLAY -- It's a Russian game - of course there will be glitches! There are a few technical shortcomings, but what game doesn't have them? The AI is not state of the art either. Armed enemies will shoot you within milliseconds of you leaving cover, so firefights are best done at distance, but to me, it did not ruin the game completely. Melee combat is fun, and although you can't block with an axe, fighting multiple melee-only opponents is fun. Enemies are hard, but you are never attacked by more than two at a time, which is perfectly fine, as most are a fun challenge to overcome. After a few playthroughs though, it might become too easy, as there are no difficulty levels. Weapons are very fun to use - all WWII era Soviet rifles and PPSh-41 SMG. Puzzles, though simple, are also a big part of the game - when you find a frozen corpse, you can see the final minutes of their lives, and you need to prevent their demise in order to advance. It's not difficult to figure out how to do it, and in some cases it seems trivial, while in others you know that only your knowledge would have saved them. It is a very cool part of the game, and this is how you figure out much of the story. Also, when you take damage, your core temperature decreases, so in order to survive you need to find heat sources and warm your hands. When the environment's temperature is low, your body heat will slowly drop to match the temperature, but heat sources are plentiful, so you will not freeze to death often.
GRAPHICS -- Although nothing technologically amazing (DX9 with 4.0 shaders), the parallax occlusion mapping makes the frost on walls look very real, and moving specular maps create an illusion of melting frost sliding down the walls and objects when you turn on a heat source, reviving the room and creating a nicer, warmer atmosphere.
VERDICT - Not your usual horror/zombie shooter, it provides a much richer experience, with a nice story, reminiscent of Soviet sci-fi novels, which perfectly matches the setting. Despite AI making firefights less fun than it could have been, it is still a great game, and it shows that many talented people worked on it.