She-Ra: Princess of Power (1985)

S1E37 The Anxious Apprentice

Ariel, Castaspella's bright-eyed apprentice, sneaks the Book of Spells out of the sorceress's study, her curiosity getting the better of her. But her innocent mischief takes a dangerous turn when Scorpia, prowling nearby, seizes the powerful tome. Now the fate of the kingdom hangs in the balance as Castaspella races to reclaim the stolen magic before Scorpia can unleash its forbidden secrets upon Etheria.