Cool game! I liked how the health and ammo were the same from the flame, that was very creative. I also enjoyed the dynamic lighting effects with the fire.
I did find a bug where when you shoot a flying enemy and it starts to glow red, if you keep shooting it the flame grows infinitely bigger.
If you wanted to improve, I suggest adding signs in the game showing where to go. I was often lost and would just fall to my death. I also suggest adding dynamic lighting to the fire pick ups, they were kinda hard to see and could help with showing the direction the player could go in. Lastly, add some more animations, when the flame dies maybe add in a sound effect, some smoke particles and have the screen fade rather then just jump cut back to title screen.
Overall fun game, what you made as super cool!