Lee Arenberg and Rose McGowan were both in another magic/fantasy related TV show called "Once Upon a Time."
There were 12 original Titans named: Oceanus, Tethys, Hyperion, Theia, Coeus, Phoebe, Cronus, Rhea, Mnemosyne, Themis, Crius and Iapetus. There was no Demetrius (but there was a female Goddess named Demeter who was the daughter of the Titan Cronus and the Goddess of Harvest) or Meta out of the original 12 Titans or their children who were the Greek Gods and other famous Greek legends that we know of today. Their lineage and names were as follows: Oceanids and Potamoi were the children of Oceanus; Helios, Selene and Eos were the children of Hyperion; Leto and Asteria were the daughters of Coeus; Atlas, Prometheus, Epimetheus and Menoetius were the sons of Iapetus; Astraeus, Pallas and Perses were the sons of Crius; and Zeus, Hera, Poseidon, Demeter, Hades and Hestia were the sons and daughters of Cronus and Rhea.
Brian Thompson, who plays Cronus, played Hercules in Hallmark's production of Jason and the Argonauts. In Greek myth, Cronus is the grandfathers of Hercules.
When Piper finds Chris reading their Book of Shadows, the page he's reading shows a drawing in the likeness of Bela Lugosi.