Agonizing Blow

By sacrificing 30 hp, plus 6 extra to gather your blood if you do not have it, you can turn the blood into swirling, blood-red mist in front of you and launch a bright red beam at the target, dealing 40 (4d20) damage and the blood mist will go to the target, blinding them as long as it stays and dealing 10 (1d20) damage every time it is the target's turn for your concentration, but you take 2 (1d4) damage every time the target takes damage this way. You can use a bonus action to dispel.