Love how the game looks. Controlling 2 characters simultaneously is hard to get used to, but not too hard, it adds to the challenge. I don't know how enemy randomization works, but I would say that it is very random. There was a run that I only encountered the triangle bullet enemy once before facing the boss. And having to face the boss upside down wasn't pleasant. Maybe make it move from up to down and vice versa instead of staying at one side? (Or maybe it already did, and I didn't survive long enough) I wasn't able to complete the game, is there any story after that?
Overall, good game.