|Voiced by||Erik Gunden|
Ghost Rat lived in Prime Evil's most secure dungeons in Hauntquarters. When Wizard Fuddy was locked up in Prime Evil's most scary and most slimy dungeon, Ghost Rat entered the spaceous dungeon by walking right through the wall. Fuddy attempted to 'take care' of the rat by using Merlin's Magic Staff, but his spell only succeeded to grow the Ghost Rat to human size.
To thank him, Ghost Rat began telling Fuddy jokes. Eventually the Ghostbusters managed to rescue Fuddy from the dungeon, who was glad to leave Ghost Rat and his corny jokes behind.
Ghost Rat first appeared in the episode Our Buddy Fuddy.