I am a sucker for retro style games and lore, the visuals and music were pretty solid. I do think the spin element could maybe be driven further, than just a spin and the boss movement. Maybe in more attack patterns and so on, like with bullet hells, though movement might have to be sped up for that. Overall I look forward to what you will add for the final release, post jam!

Edit: Since music speeds up as you get hit, maybe relating that to the gameplay a bit more would be an interesting idea, punishing the player for mistakes, but also seeking to reward their actions by getting closer and maybe using more specific attacks.