I love this concept so much. Took me a couple of tries to get it down but the rhythmic movement reminded me a bit of Crypt of the Necrodancer . The boss keeps disappearing towards the end so I can't finish them off.
Thanks! Crypt was definitely in the back of my mind when developing the game. Glad the movement felt rhythmic.
The boss disappearing means you beat it! There might be a bug where the UI doesn't update properly, but it takes 10 orbs to finish them off.