During the early to mid 1970s, Marvel Comics underwent a period of unprecedented change that resulted in the creation of characters like Blade and Moon Knight, who had a supernatural bent. With the relaxing of the Comics Code Authority in 1971, a set of guidelines that had previously banned the publication of werewolves, vampires, and zombies in American comic books, publishers like Marvel were free to create characters that they otherwise would never have been permitted to.
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