Thank you, I'm really glad you enjoyed it! For the ghosts, I modeled their shapes in Blender (basically a sphere with one end blown out), then used Unity's Cloth component to handle all the animation. I spent about a day implementing the menu stuff, just trying to figure out how complete I could make the game.
Thank you so much for your feedback. Some things were bugs I shrugged and made features, like fire-by-possession. I went back and forth on letting the ghosts pile up on you and how to handle that, but left it as I felt it created a sort of challenge to keep moving, and they don't follow you until your first death, so the longer you survive, the longer you can keep them from crowding you. Exploring underwater was something I always wanted the ghosts to do, but I need to refine the movement so it's a bit easer to move vertically.
Thanks again, and good luck to you as well!