Triage Hospitaler

Most warriors and soldiers are trained specifically to inflict harm upon their enemies or protect their allies with shields and bulwarks. When these warriors are struck low, however, they are brought before the Hospitaler, who is every bit as capable a soldier, but who is focused on treating wounds and recovering the health of their allies until they are needed on the front lines, themselves. These capable workhorses of any army are the ones able to strike with surgical precision, yet surgically restore life and reattach limbs, also. When they emerge into conflict, they support their allies with combat skill and anatomical knowledge that makes them quite capable in battle, as well.

This archetype is fairly common in kingdoms where magical healing is rare within military nations. Triage Hospitalers often make up entire medical field units that back up army encampments, and who make up the necessary garrisons of those who heal the wounds of war. As individual adventurers, Triage Hospitalers are often veterans of some former campaign who chose to ply their skills similarly to mercenaries in service to their own ends, using their skills dealing both death and life and to turn coin. Yet others serve more noble causes, perhaps in service to religions, as defenders who can protect and also heal their wards.

Healer's Talent

3rd-level Triage Hospitaler feature

You are knowledgeable in the many ways to help treat wounds and prevent the worst aftermath of injury, such as disease, poisoning, or other infections. You gain proficiency in Medicine, and gain the Healer feat. If you already have the Healer feat, you may choose another feat instead. Furthermore, if you attempt to stabilize a creature who has 0 hit points with a use of a Healer's Kit, you may do so as a bonus action instead of as an action.

Triage Zone

7th-level Triage Hospitaler feature

At 7th level, you are able to establish a zone of triage which enables those within to recover more rapidly than normal. You establish an area (typically inside a triage tent) at least 15 feet by 15 feet. This process takes 10 minutes time, or 5 minutes when assisted by another able-bodied humanoid, and you must have a Healer's Kit and an Herbalism Kit inside this space. Setting up a Triage Zone in this way uses one use of Healer's Kit. Once you have established this Triage Zone, up to four small or medium-sized humanoids who take a short rest inside this space gain the maximum number of hit points on their hit die from having spent hit dice to recover hit points. Furthermore, if a creature is poisoned or diseased and they rest inside the Triage Zone, the effects of the poison or disease are suspended (but not cured) during their rest. If a creature has suffered levels of exhaustion and they spend a long rest inside the Triage Zone, they may recover two levels of exhaustion instead of one. You can establish multiple Triage Zones, as long as the prerequisites of space and tools are met. 

Surgical Precision

10th-level Triage Hospitaler feature

At 10th-level, you are now an experienced battlefield surgeon, capable of not only recovering your allies' health, but of also reattaching severed limbs. To do so, you must establish a Triage Zone, and you must have at least one gallon of water inside the Triage Zone. If an ally has had a limb severed or otherwise completely disabled from injury, you may perform a one hour surgery to reattach said limb or to cause it to be recovered in function. No more than one other creature may be in the Triage Zone at the time the surgery is performed.

Additionally, you now possess a strong knowledge of anatomy that enables you to rapidly assess a target and know exactly how to strike a vital shot against it. You score critical hits against humanoid targets on weapon attack rolls of 19 or 20. Your anatomical knowledge can allow you to use this precision with non-humanoids, but only if you possess other corresponding knowledge, such that proficiency in Arcana, Nature, and Religion can effect this feature as follows:
Proficiency in Arcana allows you to score these critical hits on non-humanoid Aberrations, Celestials, Fey, Fiends, Monstrosities created with magic, and Undead created with magic.
Proficiency in Nature allows you to score these critical hits on non-humanoid Beasts, Elementals, Fey, Giants, naturally-occuring Monstrosities, and Plants.
Proficiency in Religion alllows you to score these critical hits on non-humanoid Aberrations, Celestials, Elementals, Fiends, and Undead.

Expert Medic

15th-level Triage Hospitaler feature

At 15th level, you are now able to battle shoulder-to-shoulder with your allies and still apply a great deal of your medical skill while fending off attackers. You gain the following benefits: You are able to use a Healer's Kit to far greater effect in healing your allies, and if you use your Healer feat to tend to a creature and restore 1d6 + 4 hit points to it, plus additional hit points equal to the creature's maximum number of Hit Dice, you are able to use that feature two additional times on the same creature before it must finish a long or short rest. You also now restore an additional +1d6 hit points with all uses of a Healer's Kit, and if you and your target are both in a Triage Zone you restore an additional die of hit points, for a total of +2d6. Lastly, if you take the Dodge action in combat, you may use a Healer's Kit in any way you are able to as a bonus action in that round.

War Surgeon

18th-level Triage Surgeon feature

At 18th level, your mastery of the physician's sciences has made you an exemplary combat medic, with the ability to pry life from the jaws of death itself. If a creature has been reduced to 0 hit points at any time within the last 5 minutes, you may still yet return it to life through your extraordinary medical skills. You touch that creature's body with a knife or dagger in one hand and your Healer's Kit in the other hand, expend a use of your Healer's Kit, and spend your bonus action and your action in this turn to restore that creature to life with 1 hit point. Even though this creature is restored to life, it must remain incapacitated or do nothing more strenuous than light activity for one week or also receive magical healing of any kind before it is able to be returned to regular activity, as you've left a large surgical wound on it's body. Once you have used this feature on a creature, you cannot use it again while it still has a surgical wound from this feature.

Additionally, you may now use rapid verbal cues and gestures to indicate to an ally how best to avoid grievous harm. As a reaction, you may expend one use of your Indomitable feature and grant its benefit to a creature you choose within 30 feet who can see and hear you.