Cool platformer with great ideas. I got stuck already at the second level, where there is two pipes. I was able to open the door with the box but never able to pass the 2 enemies with the 2 pipes above. (The game is pretty difficult indeed)
It would be great if attacking would make us stop directly. I was often holding X while moving so nothing happened.
The fire is an interesting mechanic but I feel like you should reduce a bit the throwing intervall to make it fair.
Also, I got stuck several times cause of the box. When It hit a wall, there is no way of pushing it in the other side. Maybe a carrying mechanic would be somehow appreciable.
I really enjoyed the pixel art , and the musics were insane -- It wasn't looping sadly :(
Great submission overall !