Corydon and the island of monsters - Tobias Druitt

Corydon is thrown out of his village for being born with a goat's leg. Captured by pirates and put into a freak show with other monsters, he finds out he is the secret son of Pan. He meets Medusa the gorgon, the Minotaur, the Sphinx and many other mythical creatures and, with the aid of a magical staff, manages to free them and lead their escape into the mountains. But Zeus, king of the classical gods, is alerted to their escape and forces his son, Perseus, to raise an army of heroes to pursue and kill them. When Medusa's baby son is stolen from her by Perseus, the battle becomes personal. Now not only do they face a devastating army, but they must also rescue the baby gorgon. But first Corydon must travel deep into the Underworld to uncover the secrets of the staff...