I know a few people have posted how to kill the rage ghost (including me) in the other thread it's pretty easy to kill if you know how to do it and have a freeze weapon.
3 pirates can do this:
1st pirate hit ghost with pistol.
2nd pirate hit the ghost with freeze after it comes after 1st pirate
3rd pirate kills ghost with blunder using steel shot.
You then have your new hat.