3. Mr. Mxyzptlk
Or Mxy, as we shall refer to him, is a magical imp from the fifth-dimension who, story has it, every 90 days is permitted to escape from his five dimensional realm to come to Earth to wreak havoc by using his magic on Superman (which is one of his weaknesses alongside the green K and red sunlight!), who could only be sent back into his fifth-dimensional confines by saying his name backwards (which may be even more difficult than saying it normally). Now, the magic that Mr. Mxy pulls on Superman is often over-the-top, amounting to cartoonish gimmicks fit for a film aimed at pre-schoolers, with thrilling magical exploits like turning the muscular Superman morbidly obese. Imagine the drama! "Tune in to find out how does Superman wrestle with the ultimate decision: does he want his meal super-sized?!" This clownish kid-friendly Mxy should stay on Saturday mornings, but a movie-version of Mxy should draw upon a classic retelling of the character. In 1986's "Whatever Happened to the Man of Tomorrow?", Mxy is revealed as being a much darker figure than early versions had shown, turning from "mischievous" to "pure evil", this incarnation of Mxy used his magic to injure and maim and bring out the worst in Superman, which would in turn bring out the best Supes cinematically. Imagining a sick and depraved imp weaving his dark magic to make Superman's life a living hell is much suitable to the cinemaplex than Supes coping with the traumatic effects of coming down with a rough case of donkey-voice. Positioning Mxyzptlk as an evil fiend would take it far beyond "tugging on Superman's cape" in a sequel to MoS. Say it with me now, "Namrepus!"