this is really good for a first jam
rolling around in skull mode was satisfying
i liked the effect of the bones following you
would suggest a longer song loop
it can also be difficult to avoid taking hits from enemies that come at you quickly.
some bugs i noticed:
trouble getting through gaps sometimes. this includes larger gaps meant for walking through but i noticed the most common solution for the small ones is that you can only use the boost you get from switching to skull mode (jumping doesn't work for some reason)
flying enemies stick to your head frequently
during the triple boss fight there was something pushing me when trying to jump from platform to platform on the top of the arena
also the teleporting from hitting spikes would always result in me getting hit again
also got stuck in the ceiling once
the cloud background isn't supposed to be repeating vertically