I think you did a very good work for the animation ! All the art was very good, except the UI.
It would be nice if you added something to solid color UI containers. The UI is also too small, especially the font (it wasn't rendered at GameBoy's resolution). And finally, using mouse for the menu is weird on a GameBoy as there is litterally no mouse on the original hardware.
Beside of that, the game was simple to understand
The take of the theme was a good idea, I think yours is unique.
Good soundtrack ! However, I think it was lacking a few SFX.
Good job