Hercules The Avenger (1965)

aka: La Sfida Dei Giganti

Hercules (Reg Park) sets out on a quest to save his son's soul from the evil Earth Goddess Gia. He must battle all sorts of monsters, get past numerous obstacles and resist temptations if he is to save his son. What Hercules doesn't know is that while he is away, Gia sends Antaius (her rotten son) to impersonate Hercules. Antaius reigns over the people as a cruel, heartless king. Can Hercules get back in time to save the people?