Very cool game, I really enjoyed the possession mechanic. It would be nice for it to last a little bit longer, even if it was slightly weaker to compensate as it felt like a lot of work for a somewhat mixed payoff.
If you kill too many enemies during possession, their orbs despawn by the time you go back to being a ghost.
The horn sound when collecting full courage felt out of place but was welcomed to know when my courage was full.