Speaking at a recent fan event marking the end of the third and final season, Trevor explained more about Gerbert’s so-called “alliances” throughout the series.
“I don’t know that he sees them as alliances,” the actor clarified. “He just, really, uses anybody that he can at any time.”
At various points in the series, Gerbert temporarily joins forces with the formidable witches Peter Knox (Owen Teale) and Satu (Malin Buska), among others.
He soon makes it clear he only worked with them to forward his own selfish aims, however.