Medusa terracotta temple antefix, c. 500 BC. In ancient Greek and Roman art, images of Medusa's severed head were used for protection. An antefix is a vertical block which terminates and conceals the covering tiles of a tiled roof. It also serves to protect the join from the elements. In grand buildings, the face of each stone antefix was richly carved, often with the anthemion ornament. This terracotta antefix showing her with beard and tusks was mounted on a roof to ward off evil. Medusa is one of the most well-know figures of Greek mythology. She was the only one of the three sisters named Gorgons who was mortal. The legend informs us that the goddess Athena was jealous of her beauty and transformed Medusa's beautiful hair to serpents and made her face so ugly to behold that the mere sight of it would turn onlookers to stone.