Pretty cool! I quite liked the gameplay once I figured out what I was supposed to do, and I even went through it again to get a faster time! I do have some complaints, mostly in regards to sound design. Due to the lack of a volume control system, the sound effects ended up being really loud when paired with the music which on occasion would have multiple songs overlap. It's not terrible, the songs themselves aren't bad, I just think the combination of those two issues makes it harder to listen to.
The gameplay was neat but I quickly realized that using my coins to shoot the enemies was less efficient than just running past them as fast as possible so on my second playthrough I never even shot a coin. Had the movement been a little slower and I probably would've engaged with that more. I also think that the lack of visual feedback when an enemy gets hit makes it harder to gauge whether or not you're actually doing anything. Overall this game is good, but has small issues that add up to becoming larger problems. If these issues were taken care of I think this would be a really good game.