I like the style you are going here with the 'hardcore' platformer.
I couldn't complete the whole game but what I saw was quite good.
Especially the flying enemies in the second level felt really good.
Some takeaways where you could improve:
- The platfroming felt a bit floaty/ slippery. In my experience when I land and try to stand still the character still moves a bit further. Responsive controls are really important in harder platformers.
- Maybe add a smaller easier level at the beginning. The first level already felt pretty hard for the start.
- The intentional bugs were sometimes a bit hard to spot. I think players wouldn't know what they need to do, as from a visual side there is small to no indication.
For a jam entry this is a great job you did.
Keep it on.