i like the idea and the music, a few thing i noticed:
- there is no way to see how much hp the boss has left
- I coulnd't figure out how to get the health thingy
- when you die and its not in the boss fight your but back with full health instead of restarting like it does when you die during the boss fight
- after respawning and trying to get to the boss again, when you get there the boss will already be attacking you (it shot one of it rockets during the introduction scene)
hope you can make this in to a full game