In the earlier episodes , as mentioned in the show 's opening title , Hercules ' main nemesis is his evil stepmother Hera , who seeks to destroy Hercules using various monsters , because he is a reminder of her husband Zeus ' infidelity . In the earlier episodes , as mentioned in the show 's opening title , Hercules ' main nemesis is his evil stepmother Hera , the powerful queen of the gods , who seeks to destroy Hercules using various monsters , because he is a reminder of her husband Zeus ' infidelity .