Having been in the business since the 1930s, it's only natural that DC has built up quite the cast of characters. But while superheroes like Batman, Superman, and Wonder Woman tend to hog the DC limelight, a hero wouldn't be much without its rogue's gallery, and DC features some of the best villains in comic book history. From the Joker to Scarecrow to Darkseid to Lex Luthor, the DC villain roster has no shortage of iconic characters, some of which make a mighty appearance in Suicide Squad: Kill the Justice League.