Loved the game! some minor feedback:
I had a bug where a frog guy spawned outside of the arena on stage 4.
Also, I think the MP mechanic is cool, but it honestly always felt that the most optimal thing to do was shoot all of my shots at the same time to get my mp back. It didn't make sense to stay at 1 when i could shoot it and get 3 more. Would be nice if each shot had a recharge timer maybe?
However, I absolutley love the game despite that! The controls are really fun and It was just the right amount of difficult. Well done!