finally got around to this!
quibbles:
keeping track of what powerups you have and especially what combinations of powerups do what is totally obtuse. maybe a descriptive name for each combination would be better instead of the names of the critters that're following you. each of the powerup creatures is also not so different in design to be immediately recognizable, which is a problem.
the powerup system in general is a bit difficult to grasp. if i get it correctly, by picking up enough dropped energy from defeated enemies, you receive a different kind of follower/critter/powerup that can be then combined with another one? and you lose them on taking damage? the rules here weren't evident and that left me confused.
positives:
the controls are smooth and responsive, and i never felt like i got hit when i shouldn't have. you can easily tell when you've hit enemies.
there's a distinct and bizarre atmosphere here, contributed to by the graphics, unique character designs, and nomenclature. comparing it to anything is a disservice but frankly i was reminded of the darker bits of the earlier kirby games, especially the smooth, bubbly backgrounds.
the levels are quite distinct from one another, which helps it from becoming samey, and are really interesting to boot. combine with the limited palette, fluid animations, and focused art style and the game is easy on the eyes and distinct.
overall, you've got a great and polished experience here. keep up the good work!