A god and a goddess overheard the conversation between Polydectes and Perseus about bringing the head of Medusa back as a wedding gift. The gracious Athena and Hermes gave him things such as a brass shield, winged sandals, a magic wallet and an invisibility cap to help him on his journey.
Perseus is guided to where the Graywomen live. The Graywomen have three heads and they only share one eyeball. Perseus takes the eye and refuses to give it back unless they tell him where he can find Medusa. The women tell him and this is the point where Perseus has entered the world of strange creatures.
The main test for Perseus is to find Medusa and chop off her head. His allies are Athena and Hermes because of the guidance and tools they gave him to help him on his journey. His enemies will be Medusa and the other gorgons.