Tree House of Horror X - S11-E4
Professor Frink: In episode BF12, you were battling barbarians while riding a winged Appaloosa. but in the very next scene, my dear, you're clearly atop a winged Arabian. Please to explain it.
Lucy Lawless: Ah, yeah, well, whenever you notice something like that, a wizard did it.
Professor Frink: I see, all right, yes, but in episode AG4...
Lucy Lawless: Wizard!
Professor Frink: Ah, for glavin' out loud!