Lifehunt

You've acquired the ability to drain the life force from a creature though drawing blood from it in combat, turning their lost vitality into your own. 

Before you make a melee weapon attack with a melee weapon or unarmed strike that you are proficient with, you can choose to take a -5 penalty to the attack roll. If the attack hits, you add additional damage die equal to that of your weapons normal damage die to the damage of the attack. You regain hit point equal to the amount of damage inflicted by this additional die/dice.