Eviscerate

You incant wicked words and try to touch a creature that you can see to tear the viscera out of its body. Make a melee spell attack against the target. On a hit, the target takes 8d10 force damage, and it cannot regain hit points until the end of your next turn. Until the spell ends, on each of your turns after the first, you can use your action to repeat the attack against a creature that you can see. 

If the spell reduces a creature that has blood and vital organs to 0 hit points, your hand plunges into the target's body and tears out a vital organ, leaving the wound open. Until the organ is returned to its proper location via surgery or magic, the creature is unconscious and dying, it cannot be stabilized, and it cannot regain hit points.