Dark Star Plague

Overview

The Dark Star Plague was once an ancient source of fear and devastation across the cosmos in the early days of space travel. It's unknown source caused panic and almost wiped many societies from the map. At its hight it stretched far across the stars, but suddenly, it seemingly vanished. No one knows exaclty why but cases now are extremely rare and many are false alarms.

Elarion's Wrath they called it on Sthundoth. Spacer's Bane on Kiros. Whatever the name, the mark of death was always the same: a small black starburst. Soon hundreds more would appear all over the body and spread their infection through a web of black veins. A cure has avoided science for centuries, and only the most powerful of mages and mystics stand a chance of stopping it. Should the Dark Star Plague one day return, I fear oblivion is the fate of its victims.

— Corvath; Journal of Ailments and Sicknesses of the Quadrant

Mechanics

Severity	Level IV
Type	Disease (ingested, inhaled, or injury)
Save	Constitution; DC 20
Frequency	1/day
Track	Physical
Contagious	Yes; Creatures who are within 10ft of the creature for 10+ minutes have a 10% chance of being infected.
Symptoms	The creature suffers a -3 penalty to all Charisma based checks, attacks, and saves. Upon entering the Impaired state, the creature also has it's visibility reduced to 20ft. and has disadvantage on concentration checks. Please see the Symptoms section below to see more non-mechanical symptoms.
Cure Conditions	2 consecutive saves or a Greater Restoration spell.
Death	If a creature dies with this condition, in 1d12 hours the body is completely comsuned by the darkness and the corpse is transformed into a Shadow Elemental.

Transmission & Vectors

Spread

Dark Star Plague can be airborne, thus inhaled, injested through infected water or food prepared with said fluids, or can enter the body through contact with open wounds. It's rarity and mutation rate has made it so there is little consistent research and thus bypasses many common filters.

Range

Dark Star is a mutation of bacteria. Though it magically adapts itself in many situations, it still is not able to survive rapid temperature changes or extreme temperatures for extended periods of time.
Temperatures over 110* F or below 20* F with exposure of at least 10 minutes will kill the bacteria and stop the spread or decontaminate an area. The duration required made it difficult to treat the inffected as exposure for that long at those temperatures would kill the patient before the bacteria.

Causes

No one knows what caused the original mutation of common harmless bacteria into the killer it is now. However, due to the nature of what happens to those who die from it's touch, there has been speculation the grim power of the Shadowfell was imbued into the bacteria and it made its way through many hosts to spread across the stars.
Others pose a much darker theory: the plague was intentionally created directly or with influence from one of the Night or Darkness Goddesses, Shar, Elarion, or Hecate, as punishment for a population that slighted them.
What is known, is that the plague is virtually undetectable through science. It's arcane mutation makes it incredibly difficult to detect with technology. Some say Detect Magic gives a slight necromantic vibe in the air, food, or water if it is present, though this has not been confirmed.

Symptoms

Once a creature is symptomatic, small black star-like marks begin appearing on their body. While these marks may seem innocent, even cute, they foreshadow only oblivion for those who bear them.
A few days after the dark stars appear, thin black striations, like the faintest of spider webs reach out from the star marks. The star marks and their strands continue to darken and grow and will soon pulse of their own accord. At the same time, the infected creature begins to suffer from headaches and mild nausea.
As the darkness takes hold, other creatures become horrified of the infected creature. It loses it's normal charm and is overcome with a sickly demeanor. Soon the marks stretch across the face and the eyes of the infected creature become cloudy is if covered in a balck fog. The headaches become near unbearable.
Soon the darkness takes over the eyes and the creature falls unconscious into a coma. Death is soon to follow.

Prognosis

Barring magical or divine intervention, the infected creature in a matter of days would soon be covered in the black star like patterns and overwhelmed with nausea and headaches. Soon their sight would fade and they would fall into a comma. Death always follows soon after.
Only a handful of known patients have naturally overcome the disease. Those who did were still left with a small number of darker skin spots in the starlike pattern. A reminder of their brush with death.

Symptoms

Nausea, Headaches, Skin Marking (Black Star bursts)

Type

Supernatural

Origin

Mutated

Rarity

Rare