Villains that have a split personality, or seem to have more than one personality. This can result from mental illness such as Norman Bates, an experiment gone wrong such as Lizard, a curse like that upon Gollum, multiple beings condensed into one form such as Naraku, or some other source. It is possible that one personality is good while another is evil in some cases. These villains are rather unique as a story telling device when one of the personas is good since unlike Possessed/Brainwashed villlains Villains with Dual Personalities often can not have their second selves exorcised or snaped out of it. Even when both/all personalities are evil the fight for dominance and startling shifts in motivation and method keep the heroes guessing on how to deal with them.