Hercules in dream or vision are about finding your pure self, your true strength, courage and life purpose. Hercules brings out the best in us as well as the lesser and darker qualities - the inner demons and the angel wings are reflected here. So Hercules dreams and visions can be contradictory, so listen carefully to your feelings; what applies.
Another explanation is that Hercules stands for transformation and change in life, sometimes you have to let go of the old, change before you get where you need to be. Yet another explanation is that Hercules stands for finding balance and overcoming old wounds from past lives, defeating inner demons; but you can also think of magic, spiritual growth and high energy and the higher purpose and dimension.