Phorcys



Ceto

An ancient sea-god and -goddess of the dangers of the deep, Phorcys and Ceto were the parents of several other monsters, such as the Gorgons, the Graeae, Scylla, and Echidna, the latter of which went on to have several monstrous offspring of her own.



Typhon

The 'father of all monsters' of Greek mythology, Typhon attempted to kill Zeus to avenge his defeated Titan brothers, but was himself defeated and buried under Mount Etna (presumably Typhon is what makes that volcano one of the world's most active).



Echidna

The 'mother of all monsters' of Greek mythology, Echidna was herself from a family of monsters that included the Gorgons. With Typhon, she gave birth to infamous beast such as the Chimera, Cerberus, Sphinx, and Hydra.