Way of the Plague

Monks of the Way of the Plague are obsessed with infections and diseases. They capture creatures and prepare elaborate experiments to capture, record, and improve whatever plagues they may carry. They then use this knowledge to help them reach their goal of creating the ultimate disease, and slaughtering thousands with their experiments.

Plague Vial

Starting when you choose this tradition at 3rd level, you learn to create and hurl vials of filth and disease.

You may create a disease using the options below, gaining more options and more powerful effects at 5th, 7th, and 9th level.

For 1 ki point, you may create a vial of this disease with a range of 20/60 after 1 minute. If a creature is hit, they must make a Constitution saving throw against your Ki save DC or become infected.

You become immune to disease. 

Anemia

At 3rd level, when infected creatures take piercing or slashing damage for the first time, they begin to lose hit points equal to 5 minus their Constitution modifier every minute. Regaining hit points or gaining temporary hit points resets this effect.

Dehydration

Starting at 7th level, infected creatures must drink 1 liter of water (or some other liquid) every hour, starting at the moment of infection, or take 2d6 fire damage. If the infected creature is in a dry environment, they also gain a level of exhaustion until they complete a short or long rest and drink at least 1 liter of water.

Creatures who do not need to drink water are immune to this effect.

Fever

At 5th level, infected creatures take 1d8+the creature's Constitution modifier fire damage each turn, but are allowed to make another Constitution saving throw against the disease each turn.

Hallucinations

Starting at 9th level, infected creatures must succeed on a Wisdom saving throw against your Ki save DC every hour, starting at the moment of infection, or else must roll a d8 every time they make a weapon attack. If they roll a 1, their attack is aimed north, on a 2 they aim northeast, going clockwise as the number increases.  Creatures who do not rely on sight are immune to this effect.

Immunodeficiency

At 7th level, infected creatures have disadvantage on all Constitution saving throws.

Infectious

At 3rd level, creatures who enter a 10 ft. cone in front of the infected creature must make a Constitution saving throw or become infected by this disease. Creatures must also make this saving throw if they drink from a source of liquid an infected creature drank from in the last 24 hours. Succeeding on this saving throw makes creatures immune to your disease for 12 hours.

Lethargy

At 3rd level, infected creatures lose 10 ft of walking speed, and upon infection gain 1 level of exhaustion until they complete a short or long rest.

Necrosis

At 3rd level, infected creatures take 1d6 plus your monk level necrotic damage every turn, but are allowed to make another Constitution saving throw against the disease each turn.

Organ Failure

At 9th level, every hour, starting at the moment of infection, the infected creature must make a Constitution saving throw with advantage (This advantage can't be negated by another effect) or else take necrotic damage equal to your monk level d4s.

Infected creatures are unable to complete long rests.

Paranoia

At 5th level, any creature that enters or leaves your reach, even if that creature is friendly, triggers an attack of opportunity. 

Additionally, infected creatures may make two attacks of opportunity per turn.

Pustules

At 7th level, after the infected creature is attacked, it must make a Constitution saving throw or else instantly infect all creatures within 5 ft.

Selective Infection

At 9th level, only hostile creatures are able to be infected by this disease.

Slashing Strikes

At 6th level, your religious ferver causes your fighting style to become more erratic and violent. You may use a monk weapon when taking the Flurry of Blows attack.

Diseased Flesh

At 11th level, your constant exposure to disease has caused you to become virtually immune to pain.

Reduce all bludgeoning, piercing, and slashing damage from non-magical sources you take by half your monk level, rounding down.

Additionally, you no longer bleed. (Note: Despite being incapable of "bleeding out", you must still perform death saving throws as normal).

Plagued Blade

At 17th level, your disease encrusts your weapons. You have advantage on all melee attacks against creatures infected by your disease. Additionally, you may spend 4 ki points to cause all unarmed strikes or melee weapon attacks to instantly infect the target with your disease, assuming they are able to be infected.