Congrats buddies, you have a really good game here.
I am totally in love with your art, the animation at the begin, the UI, and the environment you build.
I just think you could make better choices to your sound assets list because the background sound starts to be kind of boring after some time of gameplay.
About the first enemy, I think his animation can be a little bit better, this one you are using looks like it is sliding and shaking at the same time.
In general, the game is impressive, to become perfect, you just need to put some people to play it a lot, watch them play take some notes about their critiques, and use all of this to polish the game.