"You feel something's unlocked." !
There's a fun exploration game behind the rough presentation, small steps and relatively slow movement here, I think you should have divided the number of steps by two and still make movement a bit faster. The lack of useful feedback (you don't immediately know the enemy is dead, and can mash the gun button) make you use far too much ammo in the beginning, but since there's ton it should not be a problem as soon as you undersand that you kill zombies in 2 (1) hit. The door animation is almost long given you're generally entering then leaving a tiny room.
The Silent Hill inspiration fits the theme perfectly, I like that there are a couple of traditional dungeon mechanics (hidden door, code, even having to find the 3 books), combat is on point, just good old resource management. The cringe title voice acting is a bonus.
Overall it was a bit frustrating yet it was fun enough, I'm glad I took the time to reach the end.