Loved the art style of the game! Very creative to have a ranged attack like that as the basic attack rather than a melee attack like most metroidvanias. I would have liked to have a constant display of where my cursor was, instead of only when I moved - I would often forget where it was, and shoot opposite of the way of an enemy when I encountered one.
The game could have benefitted from some more polish (smoothing out platforms and terrain, more sound, maybe some music) but overall this was great, and showed a lot of promise. This is definitely the kind of game I'd give a try if it was fully fleshed out. Thanks for making it!