Usually, one thinks of the opposite or natural foe of a Necromancer as being some sort of white mage or cleric (or sometimes paladin).
But what if the natural enemy of the Necromancer is the Bard?
In combat there’s no contest, but the secret of bards is they weave the big magic, they weave the story-magic and the song-spell. And when a dwarven mine collapses or a dragon scours a city or the Edmund Fitzgerald wrecks in a storm there’s a bard there to weave a mournful folk-song about the event.
The bard’s song or tale memorializes the lost but it also binds the event into a tale, the wild chaos of life and death tamed by the structure of narrative and verse. All sealed with an ending and reinforced by the retelling.
And when the Necromancer pulls forth his scepter of bone and calls to the souls of the lost to rise in his service, he receives no answer. The dead do not rise because that’s not how the story ends. Too many people have heard it. Too many voices have sung it. The lake, it is said, never gives up her dead