Monsters Unleashed Edit
It was a costume with it's arms out. In the deleted scenes, it had glowing red eyes. It was possibly the candidate for the monster machine though it wasn't even brought to life in the movie.
A Pup Named Scooby-Doo Edit
The ghost is different in the show, it was partly western and it was shadowy.and it flyed.
Scooby-Doo, Mystery Incorporated Edit
Velma presents the ghost's costume to the people of Crystal Cove along with Charlie, Captain Cutler's Ghost, and the Miner Forty-Niner.