Cursed Bloodline

Dark Precision: You can tap into the malevolent energies of your cursed bloodline to enhance your combat abilities. Once per short rest, as a bonus action, you can invoke the power of the curse to gain advantage on attack rolls for a number of rounds equal to your Charisma modifier. During this time, your strikes seem guided by an otherworldly force, making it easier for you to find weaknesses in your foes' defenses and strike true.

Draining Exhaustion: Harnessing the power of the curse takes a toll on your body and mind. After the effect of Dark Precision ends, you suffer one level of stress, representing the strain of tapping into the dark energies of your bloodline.

Uncontrolled Temptation: The more you rely on the power of the curse, the harder it becomes to resist its influence. Each time you use Dark Precision, you must make a Wisdom saving throw (DC 12 + number of times you've used Dark Precision since your last long rest). On a failed save, you succumb to a momentary surge of bloodlust, gaining disadvantage on Charisma (Persuasion) and Wisdom (Insight) checks for the next hour as the curse's influence clouds your judgment and instincts.

Tenuous Control: Despite your efforts to master the curse's power, its influence remains unpredictable and uncontrollable. There is always a risk that the dark energies you channel will overwhelm you, leading to unintended consequences or even catastrophic results.