Essence Drain

You can consume the life essence of an individual to empower yourself. You can choose to attack at melee range using this feature, adding your Constitution modifier to the attack and damage rolls. It deals 1d4 necrotic damage on a hit. While you are missing half or more of your hit points, you have advantage on attack rolls you make while you do this.

When you attack with this and hit a creature that isn’t a Construct or an Undead, you can empower yourself in one of the following ways of your choice:

• You regain hit points equal to the damage dealt.
• You gain a bonus to the next ability check or attack roll you make; the bonus equals the damage dealt.

You can empower yourself with this attack a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.