Very smart take on the theme, love that you still pick the upgrades for your weapon which really adds to that whole give and take of making it more effective at taking out the enemies, but, also much more dangerous for yourself. The fact that your hearts refill each time you level up seems like a small thing, but, really adds a surprising layer to the game, with each level of the weapon being almost it's own survival challenge. Had a lot of fun and almost made it onto the leaderboard haha