Kraven the Hunter

As Peter goes to an interview with scientist Mariah Crawford, she is under attack by the villain Kraven the Hunter. After Spider-Man is able to elude him, Dr. Crawford explains that Kraven and her used to be in love but when he was seriously injured by lions she had no choice but to give him a wonder drug called the Calypso Serum, left by a former associate of hers, that can heal all wounds, but made him into a hunting crazed superhuman.