Metabot's Manual of Magical Maneuvers

Sacrificial Dagger

4-level Necromancy

You imbue a blade with a sacraficial curse and plunge it into a creature. You must make a melee spell attack against a creature in range, dealing 6d4 piercing damage on a hit.
If the attack hits, creatures of your choice within range must make a Wisdom saving throw. On a failed save, a ghostly specter appears around them and drains the life force from them, dealing 12d4 necrotic damage.   Alternatively, you can choose yourself or another willing creature as the target of the attack, instead losing 6d4 hit points on hit. If you do so, creatures make the saving throw against this spell at disadvantage, additionally, on a fail, they are frightened for up to 1 minute. Frightened targets can repeat the saving throw at the end of each of their turns, ending the effect on a success.
At higher levels: When you cast this spell using a spell slot of 5th level or higher, the damage spell increases by 2d4 for each slot level above the 4th.