The Metamorphoses by Ovid

This collection of stories told in hexametric epic verse is perhaps the defining work of all other tales of transformation and divine supernatural influence. Ovid was born circa 43 B.C in a small village near Rome, this was about the same period as the murder of Julius Caesar and the subsequent fall of Rome. The Metamorphoses are a re-telling of Greek and Roman myths and legends, Ovid describes humans being changed into animals as punishment for their sins or hubris against the gods. It is not necessary for the modern reader to have encyclopedic knowledge of ancient Rome to get a good understanding of what this work is about. Many of the books (or chapters) of the Metamorphoses are comparable to fables in which characters receive their just deserts as consequence for their actions.
One of my favourite stories is that of Narcissus and Echo (book III). A vain sixteen year old boy is obsessed with his looks, hence the term narcissism, he chases a young nymph called Echo, who he finds particularly attractive. She calls to him and her voice echoes but he cannot find her, he rests by a pool. One of Narcissus' jilted lovers than prays to Nemesis (goddess of revenge) that: 'may he himself love as I have loved him, without obtaining his beloved' (lines 521-22, book III). This prayer is answered, Narcissus stares at his reflection in the pond and falls in love with himself while Echo departs. Out of grief, he dies and his body is transformed into a flower which is, of course, the Narcissus daffodil.
The text is filled with curious stories like these which impart morals and common ideas which will be familiar to the modern reader. Not only this, but Ovid's fluid style and unerring narrative make for great reading, the hexameter verse is the perfect fit for the smooth rhythm and the language is both common and understandable yet filled with brilliant metaphor and colourful imagery.
Ovid has inspired a myriad writers of all genres, from Dante's epic verse to the magical realism of Salman Rushdie and of course James Joyce's epic Ulysses. The relevancy of the Metamorphoses cannot be understated, read this work if you ever wish to write a poem about transformation or magic.