Name a villain that could NEVER work in a film…..

Now we have had a lot of great cinematic Bat Villains. Various Jokers, a few Catwomen, one or two Two Faces and one Killer Croc. But we have still have a ton of Bat Villains that never made it on the big screen. ClayFace, Mad Hatter, Man Bat, Professor Pyg etc. But which villain would never or could never work in a film. I got to go with Scarface and the Ventriloquist. Now yes I know a lot of these characters I mentioned popped up on the Gotham TV show, never saw it myself, but films are a different medium. Different rules. I can’t see anyone taking an evilish ventriloquist dummy seriously in a movie. What are some others?