TL;DR: Survival management adventure game that poses as FPS, but penalizes you for playing it as such, focusing mainly on storyline, which is rather average by itself, and additionally requires you to juggle companions being very eager to hate you for choices you make. Due to that game loses entire momentum later on.
Post-apocalyptic, survival, horror in Chernobyl. The main hero tries to find out what happened to his wife Tatiana, who disappeared during Chernobyl disaster, and now haunts his visions. Sounds amazing on paper. Well, reality turned out a bit different.
There's a lot of parts to this game that adds together to something that's pretty fun. First you pick missions available for the day, assign which one do you want to do and which ones will your companions do, and then go do the stuff. You get dropped in one of Chernobyl's or Pripyat's areas which you can freely explore around, finding some random events, collecting materials you use for crafting and building and ultimately solving whatever the primary objective is.
Then you teleport back to the hideout. There you do base management where you see how did the assigned missions go, assign food rations to your companions (which you can have up to 5 of) and then go into period where you can chat with them, spend resources you gathered on building constructions or crafting / modifying equipment, and then go to sleep to repeat the next day. There's technological progress where first you need to craft basic workbench for things, then for more advanced stuff you have to build a laser cutter and at the end you gain access to chernobylite-powered tools for the best items in the game. Problem about that though: You can't just build anything willy-nilly, cause you need to balance a couple of stats.
Every production-related device built in your hideout takes away from base's comfort, which you need to balance out by decorating the base. Then most devices also use power, so you need to build generators. Some machines and generators worsen air quality, so you need to also build air purifiers. And when it comes to chernobylite-related stuff you also need to worry about radiation safety and build a bunch of scrubbers and anti-rad showers. Plus your companions have to be able to sleep on something, so don't forget about beds. All of that adds a bit of depth to the whole system, which I quite like.
But then past certain point you already explored all areas thoroughly, including all the spots requiring lockpicks and chernobylite burners, so doing missions is just about seeing how fast can you speedrun the location waving between enemies that never change from "basic soldiers you can stealth kill", "basic soldiers you can't stealth kill", and "chernobylite creeps". Past certain point you build everything you need and the only thing you can spend piling resources on is usable equipment, which isn't as exciting, considering that at day 20 I had the biggest gun in the game and could shoot it like a potato cannon without having to worry about materials, turning the game into Metro 2033 shootout. And I played on everything being hard difficulty, and still had more supplies and ammo than I knew what to do with by day 5, despite sending Igor exclusively onto story missions from day 3 on.
Supply overdose is where another part doesn't quite land. To hammer in the fact that Igor is a scientist and not a soldier EVERY TIME you kill a human enemy he suffers sanity damage. Annoying but understandable, but it's another thing that stops you from going in all guns blazing (having 0 sanity causes you to take constant health damage). However, if you suffer bigger wounds or get irradiated, then instead of home-cooked meds you can use a full medikit/radiation medicine you can find in levels, which I had full cabinet of by day 9. Using those also gives you sanity damage for some reason, which I don't understand. Maybe it's related to wasting the meds if you use them when you're not really that pressed for them, but I'm not sure, I always tried to use them when I actually needed to. So either you're forced to use hand-made meds which are weaker (including waking salts that restore sanity) or completely chug vodka to reset your mental state as a band-aid solution. All of this is small things that don't quite land in what they're supposed to do, instead just being mild, piling up annoyances.
But then there's the ambition of the game. Around every corner during story missions there's choices you have to make. And those aren't mild choices, every choice has a lasting consequences, going as far as creating a whole web of pathways that influence the final ending you get during the Chernobyl Power Plant heist this all leads up to, with there being a very specific playthrough you have to do if you want the perfect ending where none of your companions die.
BUT up to that point you have to manage them as well, and choices you make influences your reputation with them. And if they don't like you enough they'll just up and leave. And literally EVERY choice has you making either one or the other affected person getting miffed, while picking option one character doesn't like absolutely doesn't mean the other character likes you more because of it. A lot of the choices just make one or the other hate you and nothing else. Just to be able to recruit Olga into your party ("the tough bitch" character, with accent on bitch) with the best outcome of the situation you have to piss off 3 other teammates. While I appreciate the ambition of this system I think having choices just influence the story would've been enough. There was an attempt at alleviating the headache by making it so every time you die you go into a dimention, where you can play rock-paper-scissors by alternating all the choices you've made up to that point looking for the most favourable outcome of events. There's also construction that lets you forcefully raise companions' reputation, which just amounts to another band-aid solution.
Then, possibly the most disappointing of all, the horror the game was advertised with is limited exclusively to random events that boil down to unnerving you with broken dolls staring at you or jumpscaring you with something unexpected happening. Neither the chernobylite enemies, nor the main antagonist dubbed "The Black Stalker" aren't scary at all (the latter can be waited out if you hunker down somewhere he can't follow you, or you keep breaking line of sight, but you can also completely stop him from being able to spawn if you build enough storm delayers and do the missions quick enough).
Overall the game starts out fine enough, but past specific point (around day 16 I'd say) it just becomes a chore to manage. You do story missions less and less eagerly, cause you're afraid of what next crippling choice you'll have to make causing that one companion you don't like anyway to leave, and so game's momentum severely halts. Even Tatiana starts being a bitch, blaming the whole disaster happening on everyone and everything around, Igor himself included, and not amounting to much else than whining.