Thirsting Scalpel

You gain a +1 bonus to attack and damage rolls with this magic weapon, which deals slashing damage instead of piercing damage. When you attack a creature with this weapon and roll a 20 on the attack roll, that target takes an extra 2d6 slashing damage. If the target is a creature other than an undead or construct, it must succeed on a DC 13 Constitution saving throw or lose 2d6 hit points at the start of each of its turns from a bleeding wound. Any creature can take an action to stanch the wound with a successful DC 11 Wisdom (Medicine) check. The wound also closes if the target receives magical healing. In addition, once every 7 days while the scalpel is on your person, you must succeed on a DC 15 Charisma saving throw or become driven to feed blood to the scalpel. You have advantage on attack rolls with the scalpel until it is sated. The dagger is sated when you roll a 20 on an attack roll with it, after you deal 14 slashing damage with it, or after 1 hour elapses. If the hour elapses and you haven't sated its thirst for blood, the dagger deals 14 slashing damage to you. If the dagger deals damage to you as a result of the curse, you can't heal the damage for 24 hours. The remove curse spell removes your attunement to the item and frees you from the curse. Alternatively, casting the banishment spell on the dagger forces the bearded devil's essence to leave it. The scalpel then becomes a +1 dagger with no other properties.