A War Surgeon uses knowledge of medicine to apply debilitating conditions upon enemies and heal allies using a Healer's Kit and an Herbalism Kit.

Medical Knowledge

3rd-level War Surgeon feature

Starting at 3rd level, you begin harbor a wellspring of knowledge of anatomy and medicine within yourself. You gain proficiency in the Medicine skill and whenever you stabilize a creature using a Healer's Kit, that creature also regains 1 hit point. Because you know how to use you supplies carefully, the Healer's Kit last for 30 uses, instead of 10.

Additionally, you gain proficiency in the Herbalism Kit and can spend 2 hours making a basic Potion of Healing or a vial of Antitoxin once per day. The amount of potions you may make is equal to half of your proficiency bonus(rounded down) and they all have to be the same type. To produce these potions, you need 25gp worth of alchemical components per potion.

Your medical knowledge is also represented by your Surgical Die, which are each a d4. You have a number of these dice equal to twice your proficiency bonus, and they fuel various medical abilities you have, which are detailed below.

Some of your abilities expend the Surgical Die they use, as specified in a ability’s description, and you can’t use an ability if it requires you to use a die when your dice are all expended. You regain all your expended Surgical dice when you finish a long rest. In addition, as a bonus action, you can regain an amount of expended Surgical Die equal to half of your proficiency bonus(rounded down), but you can’t do so again until you finish a short or long rest.

When you reach certain levels in this class, the size of your Surgical Die increases: at 7th level (d6), 10th level (d8), 15th level (d10), and 18th level (d12). The abilities below use your Surgical Die.

Surgical Strike

3rd-level War Surgeon feature

Also at 3rd level, using your knowledge of anatomy, you can apply one condition to the target of an unarmed or weapon strike. Once per turn when you hit with an attack, you may expend a Surgical Die to force the target to make a Constitution saving throw against your Surgical DC = 8 + your Wisdom + your proficiency bonus. Add the number rolled on the Surgical Die + your Wisdom modifier(min 1) to the damage of the attack.

If the target fails the save, you may apply one of the following effects to that creature until the end of your next turn: disadvantage on attack rolls or half movement speed. You gain more options as you gain levels in this subclass. Those options are as follows: blinded or deafened at 7th level, poisoned at 10th level, stunned at 15th level, and paralyzed at 18th level. 

At 10th level, the chosen effect lingers for 1 minute. The effected creature may make another Constitution save against your Surgical DC at the end of each of their turns, ending the effect on it's self on a success.

You may only apply one condition to a creature at a time.

Battlefield Medic

7th-level War Surgeon feature

At 7th level, you have learned enough of anatomy to aide your allies. As an action, you can use a Healer's Kit and expend up to an amount of your Surgical Die equal to half your proficiency bonus to heal yourself or a creature within 5 feet. Roll all of the Surgical Die expended, then add your Wisdom modifier(min 1), and the target regains hit points equal to the total. Once you have expended all of your Surgical Die, you may not use this feature until you have at least one.

Additionally, whenever you use your Second Wind ability, you may add one roll of your Surgical Die to the total hit point regained without expending it.

Medical Resolve

10th-level War Surgeon feature

At 10th level, you have learned enough medicine to stave of disabling effects. You have advantage on saving throws to resist the following conditions: blinded, deafened, and poisoned. You also gain resistance to poison damage. Additionally, you can end such effects in allies granted you have a Healer's Kit. As an action, you may expend one Surgical Die to remove any and all of the previous conditions from yourself or a creature within 5 feet.

At 15th level you may end the stunned condition on a creature within 5 feet; and at 18th level you may end the paralyzed condition as well. When you gain the ability to end a condition, you also gain advantage in saving throws against it.

Bulwark of Medicine

15th-level War Surgeon feature

At 15th level, you are now knowledgeable in maintaining the health of you and your allies on a daily basis. Once per long rest, you may use a Healer's Kit for 10 minutes to examine yourself and a number of creatures equal to your proficiency bonus. At the end of this examination, you grant an amount of temporary hit point equal to your Constitution modifier(min 1) + your Wisdom modifier(min 1) + one roll of your Surgical Die. You may expend additional uses of your Surgical Die to add the number rolled to these temporary hit points. While a creature has these temporary hit points, they advantage on Constitution saving throws to resist poison damage, the poisoned condition, and exhaustion.

Relentless Doctor

18th-level War Surgeon feature

At 18th level, you have reached the epitome of surgeons. you gain expertise in Medicine. Additionally, when you have expended all of your Surgical Die, you may still hinder your enemies and heal your allies. Roll 1d6 and use that in place of your Surgical Die.

When you heal a creature using a Healer's Kit and you have no Surgical Die, you may also use 1d6 in place of your Surgical Die. The creature cannot be healed this way again until it has completed a short or long rest.