19. Black Adam
FIRST APPEARANCE: THE MARVEL FAMILY #1 (1945) Black Adam unlocks his powers by shouting the word "Shazam!", endowed with the following powers from the Egyptian Gods: immense stamina and the ability to survive extreme conditions (S), super-speed (H), strength roughly equal to Superman (A), a superman intellect as well as the ability to converse with Egyptian deity Zehuti (Z), magical resistance and also the ability to travel through time and space (A), and finally, extreme psychological conditioning and mind control powers (M). Though he is an adept fighter as his human equivalent, he is among comic lore's most feared combatants as Black Adam, all the more so given that he is often bestowed with additional powers by the Egyptian Gods, on top of the aforementioned.
18. Shredder
FIRST APPEARANCE: EASTMAN AND LAIRD'S TEENAGE MUTANT NINJA TURTLES #1 (1984) Oraku Saki, aka The Shredder, is as iconic a villain as Skeletor or even The Joker, but is sadly better known for his bumbling antics on the immensely popular kids' animated series based on the Teenage Mutant Ninja Turtles comic book, originally published in 1984. Despite his comedic appearances on TV, Shredder was a dastardly man in his original form and was involved in murder, drug running, arms dealing and would actually murder Hamato Yoshi, the owner of the rat who morphs into Splinter. This is brushed over in the animated series and movies, in which Yoshi actually mutates into the rat. As an act of revenge, the Teenage Mutant Ninja Turtles kill Shredder by throwing him from the very top of a skyscraper in New York City. In true bad guy fashion, though, Shredder is cloned and comes back to haunt Splinter and the Turtles again and again.
17. Green Goblin
FIRST APPEARANCE: THE AMAZING SPIDER-MAN #14 (1964) The Green Goblin is easily the best-known of all Spider-Man's villains, theming himself around Halloween, by way of his intimidating costume (complete with armour underneath, and a gas mask), pumpkin bombs, grenades that project ghost-like shapes, hallucinogenic gases (capable of temporarily disabling Spidey's Spider sense), and a bat-shaped glider. Most famously an identity assumed by Norman Osborn, one of his most prominent acts was the murder of Peter Parker's girlfriend, Gwen Stacey, which later led to Osborn dying in a fight against Spidey and having his son, Harry, take up the GG mantle. In the Sam Raimi movies, Norman was played with campy delight by Willem Dafoe, and Harry by James Franco (s***-eating grin and all), while in the upcoming Amazing Spider-Man 2, Harry will be played by Dane DeHaan.