A mysterious and controversial superhuman ability is to be superhumanly insane. Easily one of the most famous examples of this trait is the Joker from DC Comics, which is demonstrated in the clip from Gotham above. From what I can tell is that being superhumanly insane makes you more dangerous and unpredictable than either a sane person or an average psychopath. You are free from all mental limitations such as fear and you can also come up with intense schemes that no one would even think of until it is too late. This could lead to a borderline superhuman intellect. When I created the cyborg supervillain, Cyber Shadow in my first book, I wanted to give him superhuman insanity in order to further illustrate the psychological toll his cybernetic implants were having on him.