I never would have thought blowing up my own head would be so much fun!
Neat game with an interesting concept and cute, yet gory animations. I dug my short time playing around with this proof of concept.
I can see a lot of options for level design based around losing sight after using the special ability, also a clever way to make sense in the game world that your head is gone, so of course your sight is gone.
Some small critiques. I would have collisions with the other character so the player doesn't just run through them, at the very least I'd have the player layer above the (I'm assuming he's an enemy) enemy layer. A big explosion effect around the player starting from the head would be cool too and could also give a visual cue to the player of how big the explosion hitbox is.
Love the audio track and added touches with the background. A small suggestion for something quick that will add a lot to the background is to desaturate those layers more. It will let the character layer pop more and the further an object is the more it takes on atmospheric haze, so it's less vibrant and less saturated. This guy is my favorite pixel artist teacher and he has a great blog about it here:
https://www.slynyrd.com/blog/2018/11/16/pixelblog-11-landscape-pixeling
Overall, great entry. I had fun and I can't wait to see what you do in future rounds.