Nickelodeon/Twice Upon a Time (1983)

Cast

 * Arnold (from Hey Arnold) as Mumford
 * Wallaby (from Rocko's Modern Life) as Ralph, the All-Purpose Animal
 * Helga (from Hey Arnold) as Flora Fauna
 * Plankton (from SpongeBob SquarePants) as Synonamess Botch
 * and more