Hercacles was the son of Zeus and Alcmene. He had the gift of extreme strength.  He could strangle 2 serpents in his cradle and in manhood he killed a lion.  Heracles' main enemy was Hera, queen of the gods.  She drove him so mad, that he killed his own children and his brother.  When he recovered from his madness, he was so upset that he exiled himself and consulted the oracle of Apollo.   The Oracle told him that he must perform 12 labors.