Doctor Thaddeus Bodog Sivana is a fictional supervillain appearing in American comic books published by DC Comics. Created by Bill Parker and C. C. Beck, the character is a recurring enemy of the superhero Captain Marvel/Shazam, both of whom first appeared in "Whiz Comics" #2 (cover-dated February 1940) by Fawcett Comics. A mad scientist and inventor bent on world domination, Sivana was soon established as Captain Marvel's main archenemy during the Golden Age, appearing in over half of the Fawcett "Captain Marvel" stories published between 1939 and 1953.