I'm right at the end where you're running through the collapsing wreckage. I keep restarting at the point where you get attacked by three scorpions. Then you go into a larger room and there's two tentacles. When you kill one it spawns one of those big boss monsters. Killing him is supposed to open the door. I've managed to kill him about half the time, but then the door doesn't open, and then I just insta-die.
Either a) there is a timer on this level and if you stay in one place too long you just die for no reason, b) even on the casual setting, the scorpion can insta-kill you with its tail (if it's behind me and I don't realize it, maybe?), or c) the game is glitching.
The game glitched one time before on me and I had to restart from the save. But I've restarted it 20 times, including the next day, and it keeps happening. Game are supposed to be fun, dammit