Mortimer Khan was a forgotten son of Genghis Khan. He is conjured up by fortune teller Madame Doreeno in "Feisty Geist". In telling Heffer's fortune, he finds that in life Heffer's Mongolian ancestor fell prey to a bribe for food and ruined his plans of conquest, literally leaving them to rake muck as "muckrakers". In swearing revenge, he possesses Spunky and nearly all the things in Rocko's house, stopping at nothing to destroy Heffer, then finally being trapped in a snowglobe with Filburt's Spirit-Away paste. Mortimer Khan is voiced by Tom Kenny.