Soul-Burning Incantation

Prerequisite: Forbidden Graveyard patron
Whenever you cast a cantrip that deals damage or make a weapon attack, you can use a bonus action to empower it with cruel energy. Each creature struck has disadvantage on ability checks until the start of their next turn, and if this attack kills them or is used on their corpse, they cannot be resurrected or raised as undead by a spell cast using a spell slot lower than 6th level.