Lovely idea with an amazing art & sound to bring it to life!
I agree with Fxy comment regarding the shield mechanic, it seems underutilized and even a little out of place after you figure out that you can kill enemies with your jump.
My main issue with the game is that the platforming feels to floaty for its own good, however despite these issues the game just works and shows tons of charisma and potential, I could see this idea becoming a really good precision platformer.
Congratulations!