Very good submission, it's scope is perfect so you could spend time polishing it and it's very polished indeed, specially on the visual part and the theme is well interpreted in my opinion. I've just catched some things:
- The gap on the difficult from the first run to the second run is very high, maybe keep it progressively getting harder. Also, adding more types of enemies help with that.
- Sometimes the exp are is out of bounds (in the red area), I don't know if it's on purpose but maybe check when the cloister shrink to update it's position if out of bounds.
- Some bugs noticed: the exp/coins sounds accumulate very fast and it hurts to hear, maybe setting polyphony or something like that would solve. Sometimes I do a lot of damage on the cloister, specially when shooting to one side and flying to the other side, idk if it's just the crit damage tho. And last I think just some optimization would be nice for a browser version, on late game it was very low fps.
Anyway, it's still a very good submission, congrats!