While this isn't a major departure from other Starmage boss rush games in terms of structure or skill concepts, I don't think that was really the point here; it was more a showcase of your growing art skills, which I'm happy to see are improving! Keep it up!
Outside of the art, it's a totally respectable entry: battlers by Visustella's generator and custom tunes help the game stand out from average RTP fare, and well-paced gameplay introduces mechanics at natural narrative points so the tutorials never feel out of place. Stellar job, Starmage!