poltergeist is an angry and mind and psyhically attacking ghost, do not make it angry or else it will show you what it can, it can push you and scratch you even tho you can't see him or feel him, his force can push you, this ghost isn't that powerfull but does some damages. poltergeist f is a friendly ghost because of his name including the letter "f" as meaning it's friendly, it will help you and try to calm down the bad poltergeist or protect you, sometimes it will not help you as it depends.