Adrenaline Junkie

Your Hit Point maximum increases by an amount equal to your character level when you gain this feat. Whenever you gain a character level thereafter, your Hit Point maximum increases by an additional 1 Hit Points. If you are Below half health, gain advantage on attack rolls with melee or ranged weapons, but have disadvantage on all saving throws. Once per Long rest you can choose you resist being downed in exchange for permanently losing (Hit dice + constitution modifier + 1 health) you are instead put to 1 health.