You've done a great job with the audio and effects. I often say a simple mechanic polished is a better scope for a jam game than a game that has a ton of half-complete things and I think this proves it. The unlocked coils seem to make the game harder to play so I didn't quite see a reason why I'd want to use it. Maybe I score more or there's a higher difficulty bonus? Also switching from the large to smaller is a bit jarring, maybe a tween or something to give players a chance to recognize it? Either way, great work!