History Recap / OnceUponATimeS4E12DarknessOnTheEdgeOfTown

* DarkSecret: Snow White and Prince Charming have one involving a previous encounter with the Queens of Darkness. Whatever it is, Snow is willing to threaten to kill Ursula and Cruella to keep them quiet about it.

* MythologyGag: The vault of evil the Chernabog is guarding is on Bald Mountain, and when he reveals himself it's by unfolding from within his wings when he appeared to be a peak of rock, just like in ''Disney/{{Fantasia}}''.

** We later learn the Sorcerer was trapped inside a tree in Camelot for five hundred years, so it would have been his Apprentice who imprisoned Chernabog in the Hat (unless he's been in the hat for that long--how long the hat has existed is unknown). If it ''was'' the Apprentice, that's actually even more awesome.

* TheReveal: Unlike what was implied early in season 1, the Dark Curse was neither written nor created by Rumplestiltskin, but was taken from a hidden vault of evil. Who actually created it or how is yet to be revealed..

* YouHaveOutlivedYourUsefulness: Played with. Rumplestilskin used a variant of this trope. He left the Queens of Darkness behind because he still needed them for one last thing: satisfying the Chernabog with another form of evil so that it did not go after him.

* VillainDecay: Chernabog, [[DownplayedTrope to some degree]]. While frightening in appearance and otherwise well-designed, and strong enough that Emma and Regina together cannot defeat him, he is depicted here merely as a creature that "devours the heart of whoever is most susceptible to evil" rather than an all-powerful demon/Satan figure. He's also rather easily defeated by being tricked into flying across the town line, although whether this merely banished him back into the Hat or left him unable to enter Storybrooke isn't clear. (And in the Enchanted Forest, while the Queens of Darkness aren't strong enough to destroy him either, they're still fairly easily able to ''outwit'' him, distracting him with Maleficent's heart while the others escape out a crack in the rock, then having Ursula pull her out with a tentacle to where he apparently can't follow.)

* ItWorksOnlyOnce: Trapping a magical being inside the Sorcerer's Hat--once you've been released, you can never be trapped again. Good news for Blue and the other fairies, and the Apprentice once they can get him out. Bad news when it turns out the Chernabog got released too.

** We later learn the Sorcerer was trapped inside a tree in Camelot for five hundred years, so it would have been his Apprentice who imprisoned Chernabog in the Hat (unless he's been in the hat for that long--how long the hat has existed is unknown). If it was the Apprentice, that's actually even more awesome.

** We later learn the Sorcerer was trapped inside a tree in Camelot for five hundred years, so it would have been his Apprentice who imprisoned Chernabog in the Hat.

* OntologicalMystery: At least as far as Regina and Emma are concerned, the explanations for who the Author is, how and why he wrote the storybook, and how they could find him and persuade him to change it, are this--since even though they know how and why they ended up in Storybrooke, they ''don't'' know or understand the larger cosmic narrative they seem to part of. It's also somewhat this to the Blue Fairy/Mother Superior, since while she knows of the Author, she doesn't know exactly how or why he wrote the book either--and thanks to his disappearance, she doesn't even know where he is.