The Green Goblin
Appearing as the Goblin in The Amazing Spider-Man #14 and as Norman Osborn in The Amazing Spider-Man #37, the Green Goblin is best known as Spider-Man's archenemy. Working for years after his wife's death, pushing his son away in the process, Osborn creates a serum that gives him super strength and an insane personality. He becomes the Green Goblin, modeling himself after his childhood fear. Being the first to learn Peter's identity, he has caused many tragedies in Peter's life, such as the death of Gwen Stacy, his destroyed friendship with Harry and the disappearance of his unborn daughter.