You have a README which is great, but you'll need a License file as well (these are two main criteria for open source category). Spice up your README a little with things like emojis or screenshots.
Loving the art-style and graphics. Music is funky and fits well. Controls are slightly annoying, when I walk up to the fire dude to hit him, the character turns around without me pressing any buttons, so I end up dying, and the contact doesn't always work for hitting the enemies. Great concept and good solid base. Well done.