I'm a rhythm game player, I really like the concept of the command before shotting an ability.
Tho I always run out of "mana", dead before actually killing the boss, nerfing the boss health would helps a lot or a mana bar for resource management. Definitely would give this a higher score. Good work!
*lol, just remind the topic of the jam, perhaps this boss is unkillable even I optimize the game play.