Anastomo's Baleful Curse

Once per short rest as a bonus action, choose one
creature you can see within 30 feet of you. The
target is cursed for 1 minute. The curse ends
early if the target dies, you die, or you are
incapacitated. Until the curse ends, you gain:
- A bonus to damage rolls against the target equal
to your proficiency bonus.
- Your attacks against the target are critical hits
on a 19 or a 20.
- If the target dies, you gain hit points equal to
your warlock level + your charisma modifier