Nice staggering of the entrances. Nice shift in the middle, like if boss is down to half, but uses new tactics or brings in minions. Good job!

It's so urgent, and energetic. Both threatening and yet somehow cheerful.

Great job! It has all of the elements that make good background music for a Boss Fight: repetitive, a churning/running rhythm, a breakdown section, interesting, but not distracting sounds/instruments. (perhaps a silly side quest boss…)