Metamorphoses into monsters in Greek mythology

In Greek mythology, Medusa (; ), also called Gorgo () or the Gorgon, was one of the three Gorgons. Medusa is generally described as a woman with living snakes in place of hair; her appearance was so hideous that anyone who looked upon her was turned to stone. Medusa and her Gorgon sisters Euryale and Stheno were usually described as daughters of Phorcys and Ceto; of the three, only Medusa was mortal.

thumb|Scylla as a maiden with a Cetus (mythology)|kētos tail and dog heads sprouting from her body. Detail from a red-figure bell-crater in the Louvre, 450–425 BC. This form of Scylla was prevalent in ancient depictions, though very different from the description in Homer, where she is land-based and more dragon-like.

thumb|Henry Fuseli's painting of Odysseus facing the choice between Scylla and Charybdis, 1794–1796 Charybdis (; , ; , ) is a sea monster in Greek mythology. Charybdis, along with the sea monster Scylla, appears as a challenge to epic characters such as Odysseus, Jason, and Aeneas. The descriptions of Greek mythical chroniclers and Greek historians locates her in the Strait of Messina.

thumb|The Kiss of the Enchantress (Isobel Lilian Gloag, ), inspired by Keats's "Lamia", depicts Lamia as half-serpent, half-woman