I actually really like this! I feel like I don't understand it fully; there's a lot of stuff I wish was explained. But the overall aesthetic was awesome, and I picked up the basics of how to play pretty quick (once I figured out how to use the x key, haha).
The audio is fine, it gets kind of rough on the ears when you're low on health though, with all those layering sawtooth signals.
A real achievement for a single dev! My favourite part is the artwork.