Okay, so, it was hard to figure out what to do on the bossfight. It was also hard to predict where the big box would move on the first move, so maybe a little pause after showing the colors would be good. A sound effect for damaging the boss would be good, as well as for when a switch opens a door (sometimes I pushed a box onto the switch and didn't even realize i'd opened a door)
But that's where my "complaints" end because OH MY GOSH this was fun. Really creative idea, although I'm not sure it fits the theme TOO well, but I can see the vision. I LOVE metroidvanias and this scratched that itch to play one that I haven't gotten yet from this jam. I think visually it was great as well, simplicity is always better for game jam visuals imo because it makes something like this feel entirely polished and complete. I think this has a good potential to be expanded into a longer game after the jam is complete. I'd play it 100%