Factual error: The conversation between Taylor and Michelle tells us that school is over for the day and that Taylor talked to her crush at lunch. When the boy shows up at the bakery later, he and Taylor plan to meet at 3 that afternoon; if its before 3, they should still be in school.
Factual error: Somewhere in season one Mary refers to Germany. But since this was set in the 16th century it would've been Prussia.
Factual error: In the last minutes, the show looks forward to future challenges, in effect a preview of the never-made 3rd series. The oracle says they must find "the golden fleece, woven long ago by the Stygian witches." But the golden fleece, or indeed any fleece, is not a woven fabric. (Today's fleece is a modern invention).