Lovely graphics, well made game! I included it in my LowRezJam compilation, if you’d like to take a look :)

I really like the art style -- awesome twist on the original :) The graphics and sounds are great, and the enemies are terrifying.

Minor input comment: I'd like to be able to climb up or down a ladder as I'm walking by, but I had to let go of the left/right arrow keys before being able to climb.

LOVE the colour palette (and art in general). Some really neat mechanics going on as well and I'm impressed that you managed to incorporate the bonus objectives (I didn't even know they were a thing!). 

Important reminder: We don't all use the same keyboards, so I'm not sure I'd suggest z and x for the controls (in my keyboard, the y and z are reversed, meaning my fingers are spread weirdly on the keyboard)That made the game harder for me, especially since the z key on my keyboard is on the right instead of the left
It's pretty hard. It would have been nice if the game was a bit easier at first, the time to get used to the controls. Especially since enemies respawn, creating situations that you can't get out off (got at the beginning with 3 monsters chasing me)

Not sure how I'm supposed to rate the audio since it's not your content (the music)? Original content would have been nice in my opinion, or at least not something as recognizable; as much as I like Toby Fox's tune, if I hear them in another game than Undertale, I find it a bit difficult to get "into it"

A lot harder than I was expecting (I really couldn't get the timing for killing enemies, and infinite respawn made me sad; I came nowhere close to beating level 2), but cool entry overall! Very nice graphics and sound.