As a Quack, you are experimenting with bodies. Not your body, but bodies nonetheless! You may perform surgery to examine a body, noting recent damage and any diseases or infections in their system. Upon succeeding in a Medicine Check (DC 8) you may remove the diseased or infected portions of their body, ending all diseased, poisoned, and infected conditions. You may also heal the creature by 1d6 + Intelligence mod of hit points. At the 4th tier, your healing increases to 2d6 + Intelligence mod. At the 6th tier, it becomes 4d8 + Intelligence mod. At the 8th tier, it becomes 6d10 + Intelligence mod. The surgery takes 30 minutes. However you may spend any number of Treatment Dice to reduce this time, at 5 min for every 1 Treatment Die (6 dice would reduce the surgery time to one action). If this was done during a short rest, the creature still gains the benefits from its hit die.

If interrupted you must make a Constitution Saving throw (DC 10 + any damage dealt to you). On a success, the surgery is salvaged and the patient takes a dice roll based on your tier (1d6, 2d6, 4d8, 6d10) as necrotic damage but wakes the next turn. On a failure, the patient begins bleeding out, they are unconscious, and they begin taking 2 of their Hit Dice in necrotic damage at the end of each of your turns. You may stop this bleeding by making a successful Medicine check (DC 15).