Mr. Mxyzptlk

Mr. Mxyzptlk or Mr. Mxyztplk is a supervillain that enjoys tormenting Superman.

History
When Bart was thinking at Sideshow Bob was trying to kill him again he said to Lisa at its like he is Superman and he's Mr. Mxyztplk. Lisa said then at isn't that Mr. Mxyzpltk. Comic Book Guy passed them by them and said them at actually both are correct. When Lisa asking what he was doing here he told them he answer useless trivia.

Non-canon
The names Comic Book Guy wishes to be called by Xena is Obi-Wan, Iron Man, Mr. Mxyzptlk, and Big Papa Smurf.