The game feels very polished, but it was very laggy for me when I tried to play it. It would have been nice if there was an executable version of the game in addition to the browser, because that would probably have ran more smoothly.
Edit: I also would like to say that I really liked the way the game introduces the enemies, and found the sound effects to be very satisfying! I also think the inclusion of an easy mode was a really good idea, though the game still takes a lot longer than the average jam entry to complete, even with the easy mode.