So when I heard about the competition, I started listening to some tracks. Eventually I found one that reminded me of an old idea I once had. A boss battle that never ended, the boss just got stronger and stronger with more attacks. Your score would be whatever level the boss was at when you died. So I started working on it right away!
The player is the guy with the cape.
The battle is fought on the edge of a cliff. Farther to the right is a tall boulder that cannot be leapt over.
I'm pretty happy with it so far. Also, does this screenshot *cough* remind you of anything?