Good game, my main issue not knowing whats goings to kill me lol, perhaps that is my lack of platforming experience? Due to your monochromatic art style, indicating hazards may have already been challenge? A suggestion might be Motion? the monsters move and are clearly hazardous so maybe the ground were to move or be in some animation.
The music was Great loads of Devs have done good music for this jam so well done seriously! Im kinda liking the simple jump mechanic too, it felt responsive. I Love this kind of art style as well, brings lots of atmosphere and i liked the silver touch, Great job!