Epitaph of Finality

You point at a creature within range and reveal to it the secrets of its mortality as tendrils of black fire envelop the creature. The target must make a CON save. On a failed save they take 6d10 necrotic damage. If the target would be reduced to 0 hit points by this spell, they become an undead servant to the caster for 8 hours. After this duration, the body is reduced to ash. On a successful save, they take half damage and suffer no other effects.

At Higher Levels. When you cast this spell using a spell slot of 7th level or higher, the damage increases by 1d10 for each slot level above 7th. If the target would be reduced to 0 hit points as a result of this spell being cast at a higher level, the duration of their servitude is increased by 8 hours for each slot above 7th.