It seems like The Callisto Protocol was developed by people who never in their life saw any videogame besides Dead Space, and even then they've only watched a let'splay of Dead Space.
The level design is absolutely atrocious. There maybe four or five instances in the entire game where there is more than one path forward, the progression is more linear than in Call of Duty. One time I was surprised when I saw two opened doors close to each other indicating two different ways I could take, but then I walked through one of them and realized that they both connect to the same corridor. In one of the earlier levels the game teases with potential backtracking mechanics by giving you an electric fuse and three doors that can be unlocked by using it, but after that the fuse mechanic turns into a glorified key hunting. The levels are also so cramped and your FOV is so low quite often you can't even see wtf is going on while you beat your enemy. And don't get me started on the constant need to slowly shimmy through narrow gaps or slowly crawl through ventilation shafts, it's absolutely aggravating. These are not even hidden loading screens, they are only here just to waste your time. The game is so aggressively linear it locks doors behind you without any good reasons, preventing you from going back to a vending machine or picking up missed items. One time I managed to go back to a previously explored area to pick up some items I wasn't able to take before due to a limited inventory capacity, only to realize that I can't even interact with them.
You never get an impression that Black Iron Prison is a real location where people used to live and work. Only three areas in the entire game reminds you that you're exploring a real place - one is the first area in the game (where you see prison cells, an infirmary, and a shower room), one is a hydroponic garden, and the other is a shanty town you visit near the end. The rest of the game is comprised of the same copy-pasted concrete tunnels, copy-pasted blood-stained corridors, copy-pasted shit-smeared pipes, copy-pasted rusted industrial machinery and copy-pasted sewers. Prison? Colony? May as well be a military base, or a factory, or some abandoned warehouse, or a waste processing plant.
The usual survival-horror mechanics (such as resource/inventory management) are also piss poor and badly thought out. For some inane reason the default inventory capacity you start the game with is ridiculously small - you have only 6 slots, health kits/kinesis batteries don't stack, ammo stacks are tiny, and the various sellable items also take inventory space. So if you're playing carefully and conserving your supplies, you're going to have to constantly drop excess items (and you won't be able to backtrack to pick them up later).
The game has a Dead Space-style adaptive loot system, which means enemies/supply lockers/breakable crates will always give you ammo for the exact guns you're currently carrying. Except unlike Dead Space games, there is no way to offload the weapons you're not using into a storage - you'll always carry them with you. So the game basically punishes you for acquiring new weapons by diluting supply drops and swarming your already tiny inventory with unstackable ammo types. After realizing this I had to reload a save point before crafting a shotgun, otherwise I'd have to manage two ammo types instead of just one. The game also has 'instant health gel' that drops from enemies if you're healthbar is in yellow or red zone, and this instant health gel makes normal portable medkits obsolete, as the gel heals you instantly without needing to put it into your inventory or watch a lengthy animation of the main guy injecting it into himself. I just treated all portable health injectors as a sellable junk, and never used one in the entire playthrough.
90% of the game you fight only four enemy types - zombies, spitting zombies, suicide bombers, and mutants that can crawl on walls. Normal zombies, fat zombies, skinny zombies, mutated zombies, blind zombies - they all behave the same. Well technically there are also worm-enemies and tentacles that sprout from coccoons, but they are basically glorified QTEs, and you defeat them by mashing "interact" button. There are also security robots, but they're only encountered two times in the entire game, and they pose zero threat since you can kill them by spending less than a half of your starting pistol's magazine. Uninfected prisoners? Armed security personel? Attack dogs? Wild local fauna? Nah, that would be too imaginitive for this game. Zombies it is. You never even encounter some wild-looking mutants like in those Resident Evil games, it's always just lame zombies - even the bosses in this game are just big dudes with a lot of health, even the final boss is just a dude (who also looks like
Shrek). Why? Because for some reason the game is a beat-em-up, so every enemy must be have a humanoid form for the combat to work.
And the combat is absolutely brain-dead. Dodging doesn't require any reflexes, you just have to hold either "right" or "left" buttons, and your guy will automatically dodge to the corresponding direction. There are also no crowd-control mechanics - each time you encounter more than one enemy, the ones you're not currently engaged with are just going to chill nearby while making threatening noises. There's no need to keep proper spacing, your guy will automatically "magnetize" to the closest enemy when you swing a baton. And even though it's a melee-focused game, there is no need to learn attack patterns, you just have to click-click-click and maybe stomp once the enemy is on the ground. The game also has "blocking", but your block is utterly useless (it is way easier to dodge). Enemies can block too, but you don't need to keep that in mind because one of the first melee upgrades in this game let's you automatically break through any block.
Other than a security baton you also get a bunch of ranged weapons. Dead Space had two types of plasma cutters, a military rifle, a flamethrower, a circular saw, a stasis module, etc etc. The Callisto Protocol has a pistol, a bigger pistol, a shotgun, a bigger shotgun, and a rifle (which functions like a pistol, but has a bigger ammo capacity and a burst-fire mode). Really creative guys.
This game is basically an action-horror equivalent of The Order 1886. Great visuals, great animations. Everything else is shit.