Bhaal-Touched.

Whether it be that your lineage has you as a Bhaalspawn, or one of your family encountered one of Bhaal's many worshippers. This has left your very essence touched by the lord of murder. When you take this feat, you gain: 

Ability Score Adjustment: You may increase your Strength, Constitution, or Charisma by 1 to a maximum of 20

Blood Toll:  Once per turn, when you hit a creature with a melee attack roll. You may expend a number of hit dice equal to half your proficiency bonus and add the damage to your attack.  This damage is either necrotic damage or your weapons' damage. You take damage equal to half the necromantic damage dealt. This damage cannot be reduced or prevented.

Mark of the Murder God: You learn the fear spell and can cast it once per long rest without using a spell slot. Charisma is your spellcasting ability for this spell. you may cast this spell with spell slots if you have the spell casting feature.