you should create a ghost that can become all the ghosts you've captured since the beginning of the game, and with this ghost you can use the animations you've also discovered since the beginning. (it's an idea)
I have two plans for such ghost. Will decide between them when I'm making it.
21. Darkness
22. Manifest (No cat ears though)
23. Watergirl
24. Don't Look
25. Doppelganger (Ted female form)