Base Class: Rogue
You have studied the humanoid body on a more intimate level than other rogues. While others know the best place to stab and kill, you also know how to repair the wounds you inflict, as well as how to make them even deeper. You delve into the secrets of the body learning as much medical knowledge as you can get your hands on regardless of how dirty the work becomes.
Swift Surgery
Starting at 3rd level, you know how to quickly patch wounds, given the right tools. As a action you can expend one use of a healers kit to tend to a creature you touch. The creature can spend one hit die and roll it, adding it's constitution modifier and you intelligence modifier. The creature regains hit points equal to the total. The creature can't regain hitpoints from this feature again until it finishes a short or long rest.
General Practice
When you choose this archetype at 3rd level, you gain proficiency with medicine if you don't have it already, and you use intelligence instead of wisdom on checks made with the medicine skill. Additionally, you can expend one use of a healer's kit to help revitalize your wounded allies during a short rest. Upon completion of the short rest, if any creatures regained hitpoints, they add an additional amount equal to your intelligence modifier.
Debilitating Strike
At 9th level, you learn to apply your anatomical knowledge
in direct combat, hindering your targets by attacking
weak points in their biology. When you deal Sneak Attack
damage to a creature, you can choose to forgo rolling
three of your Sneak Attack dice to hinder the creature.
The target must succeed on a Constitution saving throw
(DC 8 + your proficiency bonus + your Intelligence
modifier) or suffer one of the following effects of your
choice for 1 minute:
Bleed. At the start of each of the target's turns, it loses
2d6 hitpoints due to blood loss.
Hamper. The target's move speed is reduced by 15 feet,
and it has disadvantage on Dexterity saving throws.
Pain. The target has disadvantage on attack rolls and
Strength checks.
Constructs, oozes, and creatures without appropiate
physiology are immune to these effects. For example, a
Skeleton can't bleed or feel pain, but it can be hampered.
A creature can only suffer from one of these effects at a
time. The creature can repeat the saving throw at the end
of each of its turns, ending the effect on itself on a success.
Dosage Control
Starting at 13th level, your knowledge of medicine allows
you to refine potions into a more concentrated form,
seemingly doubling or even tripling their usefulness. Over
the course of 1 hour, which can be done during a rest,
you can refine a potion of healing. When a
creature drinks the refined potion, they roll a d20. On a
result of 11 or higher, the potion is not consumed and can
be drank again.
When using this feature, you must make
an Intelligence (Alchemist's supplies) check, with the
DC determined by the rarity of the potion. The DC for
a common potion is 10, and it increases by 5 for each
increase in rarity of the potion (15 for uncommon, 20 for
rare, 25 for very rare, and 30 for legendary).
On a success, you refine the potion. When a creature
drinks the refined potion, they roll a d20. On a result
of 11 or higher, the potion is not consumed and can be
drank again. On a failure, the potion is unaltered, and
you can't attempt to use this feature on the potion again.
For added risk, a failure could instead lead to the
potion being entirely wasted.
Peerless Physician
At 17th level, your knowledge of medicine is unmatched,
and your capability in healing rivals that of great clerics.
When a creature benefits from your General Practice
or Swift Surgery features, they use the highest number
possible for each of their Hit Dice spent, instead of rolling.
Additionally, a creature who drinks a potion of healing
refined by your Dosage Control feature uses the highest
number possible for each die, instead of rolling for the
potion's healing.