Order of the Blight Master

Many of these Blood Hunters help treat the sick and study diseases. When the Hunters are done healing a patient they will store a sample of the diseased blood and modify it. They will use the disease they cured as a weapon against the things that go bump in the night.

Tool Proficiency

When you join this order at 3rd level, you gain proficiency with Herbalism Kit.

Rite of Pestilence

Rite of Pestilence. Your rite damage is poison type. The damage you suffer from this rite is halved.

If you hit a creature with your Rite of Pestilence, it suffers additional poison damage equal to your wisdom modifier.

Upon reaching 11th level your Rite of Pestilence circumvents poison resistance.

Honed Blights

You are your primary test subject in your search for cures, resulting in your blood becoming highly contaminated.

Starting at 7th level, when an enemy attacks you, you can take a reaction forcing the enemy to make a Constitution save (8 + proficiency bonus + Constitution modifier) or be poisoned. If the target is already poisoned the target takes poison damage equal to your Blood Hunter level.

Grand Physician

Upon reaching 11th level you've learned to better understand the various diseases that torment the world, enabling you to heal those in need more efficiently. You gain advantage on Constitution saving throws, resistance to poison damage, immunity to the poisoned condition and disease, and you gain proficiency in medicine checks.

Master of Transfusion

At 15th level, whenever you see a creature drop to 0 hit points within your movement range, you can use your reaction to move up to them and stabilize them. 

Additionally, you can use an action to transfuse your blood into an ally within 20 feet of you, either healing them an amount equal to your character level, or counting as a cast of the lesser restoration spell. When you use this ability, you suffer damage equal to your character level.

Contagious Cloud

Upon reaching 18th level, the relationship between you and the contagions you carry has become a symbiotic one. As an action, you radiate an invisible cloud of disease up to 10 feet around you at all times. When an enemy creature starts its turn in the cloud, they take poison damage equal to 10 + your Constitution modifier, and you gain temporary hit points equal to 5 + twice your Intelligence modifier.

Additionally, you are immune to poison damage.