Sawbones

Not all rogues lurk in the shadows with knives or delve in ancient ruins. Some put their dextrous talents and keen minds to work healing other adventurers and working in hospitals. These rogues don't use magic or a god's power, but their own experience and knowledge that they have gained from years of practice to perform surgeries, create medicines, or at least try; the less formal nature of their training can lead to some unfortunate slip ups. These rogues are most commonly called sawbones.

Medical Knowledge

by third level, your medical abilities come into their own. You can decide your medical specialty: doctor or healer.

Doctor

Doctors use their intellect and training to heal the wounded. You use your Intelligence modifier for Medicine checks instead of your Wisdom modifier. Additionally, once per long rest you can use an action to remove the stunned or poisoned condition from a creature within five feet of you as long as the condition would end within an hour. 

Healer

Healers rely less on knowledge and more on intuition, or sometimes even faith, to heal their patients. Whenever you successfully use your risky treatment ability, you and the creature you healed gain temporary hit points equal to your wisdom modifier.

Risky Treatment

You can spend a minute and expend one use of a healer's kit to attempt to heal a willing or incapacitated creature within five feet of you. At the end of the minute, make a medicine check with a DC equal to 10+ the amount of hit points the creature is missing divided by 10 (rounded up), to a maximum of 30 total DC. On a successful check, they regain hit points equal to a roll of your sneak attack dice. On a failure, they take damage equal to a roll of your sneak attack dice divided by 2. If you stop the treatment early, or you or the patient take damage during the treatment, make the medicine check early, but the patient gains no HP on a success. Once you use this ability on a creature, you cannot do so again until they finish a long rest.

Cure Disease

starting at 9th level, your training as a sawbones has given you the ability to identify and treat disease. You can use an action to make a medicine check with a DC equal to the DC of the constitution save to avoid catching the disease + 5 to attempt to identify a disease afflicting one creature you can see. On a success, you know what disease it is, as well as it's symptoms.

The next time you use your risky treatment ability on the creature, you can cure the disease on a successful medicine check of the DC of the constitution saving throw to avoid catching the disease plus 10. Your DM might decide that you do not know of a disease, or how to cure it, if the disease is magical, exceptionally rare, or of a similarly unknown nature.

Efficient medicine

Beginning at 13th level, you can use your Risky treatment ability as an action once per short rest.

Master Sawbones

At 17th level, your medical skills are such that you can perform miraculous feats of healing. You can spend one minute to cast either lesser restoration or greater restoration without any material components or spell slots once per long rest.