Of (very) minor things:
- I might suggest to move health to the bottom of the screen - right now there is usually no time to look all the way up to see if you can take one more hit or no.
- Boss healthbar is not really clear as boss healthbar :) Maybe make it red and move a bit higher?
- The music is really nice, but Boss music doesn’t loop. It just stops abruptly and resets to “normal music”. Breaks the heat of the moment a bit.