I really enjoyed the music and sound for this one quite a bit. I too would have liked some visual feedback on my sprite for damage, but the UI was clear enough that I could at least check how I was doing at any given moment. The bosses were a lot of fun theme-wise, but I would have like to see some sort of transition information for attack changes. I really liked the trailing screw encounter, but would have appreciated a little bit of drag on him to make retaliating more accessible.
Ultimately, a lot of fun, and the gameplay was compelling enough that I went through all of the bosses!