Board Thread:General Discussion/@comment-12055413-20151010180340/@comment-23932365-20151010192842

True, Charmed really lost its footing after season 4. I highly doubt that the same thing would happen to Once, because there are plenty of stories left to tell.

There's a way to tie the Darkness into a Greek Myth arc. It could be Erebos, the primordial god of darkness. In the myths, Erebos' dark mists were drawn across the heavens by his wife Nyx, bringing night to the world. And incidentally, Erebos is a name sometimes used for the Underworld.