Really good stuff as always Nate! I didn't even get to the power ups until after my third death, and at that point the game got real good.
Solid, replayable gameplay, and the power ups just make me want to keep going and see how powerful I can make my guy. I'll often leave 1 enemy alive and collect as many coins as I can until they kill themself.
Nice clean art, and you did a great job with the UI portraying what was happening. I was never confused at any point. And of course, the music is great.