The legendary hero known for slaying the Minotaur is Theseus. According to Greek mythology, Theseus, a prince of Athens, ventured into the labyrinth built by King Minos of Crete to confront the Minotaur, a monstrous creature that was half-man and half-bull. With the help of Ariadne, who provided him with a ball of thread to navigate the labyrinth, Theseus successfully defeated the beast, symbolizing the triumph of human ingenuity and bravery over chaos and disorder.