After pushing a broom for centuries, Merlin's apprentice, Douxie, springs into action when the great sorcerer asks him to find the Guardians of Arcadia.
- Combined Energy Attack: The Arcane Order hits Camelot with a combined blast of all their magics.
- Continuity Nod: Archie meeting Toby, AAARRRGGHH!!!, and Steve plays out exactly how 3Below ended.
- Heroic Sacrifice: When Skrael sends several ice bridges to trap Camelot and give the Arcane Order a way to board, Galahad drives one of Camelot's towers into the ice bridges to free the flying castle.
- Human Popsicle: Jim is encased by a green crystal to prevent his death.
- Ominous Floating Castle: The Castle of the Arcane Order is this, complete with a skull-shaped gate to really hammer in that the Arcane Order is not interested in diplomacy.
- Put on a Bus: Toby, AAARRRGGHH!!!, and Blinky are left behind in the present, being absent while the others are in the past.
- This Is Gonna Suck: When Merlin sees Bellroc, Skrael, and the Green Knight about to hit Camelot with their combined magic, all he can say is "Oh, sod it all."
- Uncertain Doom: It's not shown on-screen whether Galahad in the present survives his fight with the Arcane Order, but Merlin's somber "Goodbye, old friend" and the fact Galahad never shows up again would heavily indicate that he is dead.
