The idea of gaining powerups as you die is cool, though I'd suggest trying to give the enemies more attack patterns because right now if you stand in front of it and slightly to the left it can literally never hit you. Turns the game into a big of a slog fest where you're just moving to the side and spamming attack. I do think the idea is cool though and it's definitely something to stick with, it could just use a bit more enemy/arena variety to make it more exciting to play.