Slayers (1995) : 1x12

Lina's Dragu Slave spell works tremendously well on bandits. Impressed, Amelia insists on learning Lina's sorcery. However, Lina is concerned by Amelia's reckless ways and orders hard training for Amelia, instead. However, the training has little to do with actual sorcery. Impressed by Amelia's enthusiasm, Phil asks Lina to show his daughter the Dragu Slave. Lina's incantation breaks the seal of ghosts and throws the Kingdom into a chaos. Lina is not well versed in white magic and fights a tough battle with the ghosts. Just when they think the Kingdom is going to be destroyed, Amelia saves it with her white magic. Amelia finally understands that she doesn't have to practice a powerful incantation.