There was ghosts and goblins, but they didn't live in minecraft world..
In the minecraft world theres zombies skeletons spider and silverfish, But i think Notch sould add some Ghosts so people don't have to make so much mods of some anyway to the story
People were in houses, all peacful and stuff.
But then all the sudden ghosts came to haunt people
So i just called ghostbuster xD