Throughout many fail of this design due to my depression, i will want to make this clear....
As a ghost, they only left is energy, and some could go through walls, invade living beings to control them to get what they want, and telekinesis non living object to fear those around it,
tho sometimes ghosts are not 100% invisibility, some people could see and some could not maybe due to their natural instinct, most ghost are in somewhat a reason they are their location
like houses, lake, park anywhere, neither they are angry/sad, want to see someone for the last time or even stuck, ghost could curse someone for whatever they did from drain the