From the online hit "Dragonball Z Abridged" created by Team Four Star, Ghost Nappa is the awesomely hilarious poltergeist Nappa becomes after Vegeta kills him in Episode 9.
Nappa was quickly established as everyone's favorite character, and to keep him in the show, Team Four Star invented Ghost Nappa. Those clever bastards.
Nappa's most awesome and powerful form, greater than vegito and SSJ4 Gogeta, can torment Vegeta, identify Pokemon and sing the theme song for a popular 80's movie