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Diseases – Fat Goblin Games

With less magical healing, disease is a very real danger to the inhabitants of the Mists. Mundane diseases claim many lives, and magical disease are even more terrifying.

Ashen Inflammation

This disease is a mounting fever that eventually consumes its victims in fire. Those coming into contact with infected individuals, or the ash of the immolated victims must make a DC 13 Constitution saving throw or become infected. Creatures that do not breath receive advantage on this saving throw.

The first symptoms of the disease appear in 1d4 + 1 hours, as the infected begin to develop a heavy fever and rash. The infected creature suffers 1 level of exhaustion; while the infected creature has at least 1 level of exhaustion they are also vulnerable to cold damage. At the end of each long rest, the infected creature must make a DC 15 Constitution saving throw. On a failure, they take 2 (1d4) fire damage for each level of exhaustion they possess and gain another level of exhaustion. On a success, they take no damage and lose a level of exhaustion. If the creature reaches level 6 of exhaustion, they burst into bright flame and then become a pile of loose ash. All creatures within 10 feet of the dying creature must make a DC 14 Dexterity saving throw or take 27 (5d10) fire damage on a failed save, or half as much damage on a successful one. Once the infected creature loses all levels of exhaustion, the disease ends.

Calcification Virus

This virus slowly turns the victim’s bodily fluids into a solid calcified substance. Sufferers typically suffocate on their own blood well before their blood completely calcifies. As the body decomposes, fluids calcify as well, until the body turns into bones and dust.

The dust carries the disease and can become infectious if breathed in or ingested. Creatures exposed to the disease must make a DC 14 Constitution saving throw or become infected.

Within a day, the victim begins to feel pain and fatigue. After 3 days, the creature begins to develop rough patches over the skin that feel hard and thick.

At this stage, the creature has disadvantage on Constitution checks (but not saving throw). After 8 days, the creatures become blind and develops stiff joints, gaining disadvantage on Dexterity checks, as well as reducing their movement speed by half.

After 18 days the infected creature must make a DC 12 Constitution saving throw every hour or begin to suffocate. There is no cure for the crystal virus.

Creatures suffering from the disease remain infected until the disease is cured with magic or they die.

Curiously, if an infected creature has their shape changed, they may attempt another save to end the disease when they return to their original form.

Marblewife Syndrome

Though some legends tell of master crafters creating lovers out of stone, this disease was named for such a fable. The disease turns its victims to stone and can be contracted by a not yet petrified victim, as well as during “spore” seasons in which the petrified victim gives off a fungal-like shedding that can further affect other creatures. These seasonal spores complicate attempts to unpetrify victims, which often leads to the destruction or entombment of victims that might otherwise be cured.

After physical contact with an infected creature, a victim must succeed on a DC 12 Constitution saving throw or become infected. If an infected statue is sporing, a creature that comes within 20 feet of the statue must make the same saving throw. Sporing statues are covered with a flaky substance that resembles dried paint.

A victim begins to lose points from their Dexterity score at the rate of 2d4 per 24 hour period. If this results in a Dexterity score of 1 or less, the victim becomes petrified. Any means of unpetrifying the victim will also remove the disease, and infected individuals also can benefit from either any means that remove disease or that remove the petrified condition, both of which cure the infected.

There are dreaded tales of entire cities succumbing to this disease, drawing in the curious and the greedy, only to add to the grim menagerie of lifelike statues.

Marrow Ooze

Though not technically a disease, the marrow ooze parasite nonetheless infects its victims with its presence. A marrow ooze enters the body through a wound or exposed orifice (potentially the mouth or ears) while the victim is sleeping, and begins to consume the host’s marrow. The victim can make a DC 13 Constitution saving throw to resist the infection.

On a success, the marrow ooze escapes avoiding being destroyed by the host’s immune system. On a failure, the host is infected but actually feels better than ever. Infected creatures begin to look more attractive, and are healed of any bone deformities, bone conditions, or diseases of the blood.

Each day thereafter, an infected creature must make a DC 13 Constitution saving throw. On a failure, the host reduces their hit point maximum by 10, to a minimum of 1. Once the host has reached this minimum, the marrow ooze splits and horrifically transforms the host’s limbs into new marrow oozes in a process that resembles the melting of a piece of wax. The host is left without limbs, but their hit point maximum is restored.

These victims are at increased risk of developing a traumatic insanity.

A host that succeeds at two saving throws (they need not be consecutive) can expel the creature, though the expulsion process is painful and difficult.

Once the expulsion process begins, the host begins to bleed from every orifice and loses body fluids through violent and frequent body emissions.

This process reduces deals 2d6 piercing and 2d6 poison damage unless the host receives proper medical care (requiring a DC 15 Wisdom (Medicine) check). If a victim should die due to this violent process, their insides are liquefied, and 1d2 marrow oozes emerge from the body.

Risen Sickness

Among all disease, few are as feared as risen sickness. Fabled to have toppled empires, this sickness creates undead with staggering efficiency, and at the least ensures a culture of fear and paranoia.

Even the rumor of risen sickness is enough to rally mobs to stamp it out, and kings have been known to wipe out entire communities as a safety measure, whether it was merited or not.

What is not certain is how the disease starts, but when it does, corpses begin to rise and hunger for flesh. This disease often spreads to long-dead corpses who have no resistance to the disease whatsoever, and swell the ranks of the risen.

Walking corpses are considered zombies, replacing their slam attack with a bite attack that imparts the infection (+3 to hit, 5 ft. reach, one target, 1d4+1 piercing damage). These corpses infect their victims with a disease that kills and raises even more walking corpses. An individual exposed to a bite must make a DC 17 Constitution saving throw. Failure means the victim is infected. After every hour of infection, the infected creature loses 2d6 hit points from their maximum. If this maximum reaches zero, the infected creature dies and rises as a zombie within 1 minute of death.

There is no simple cure for this disease outside of magic, though there are special herbs that can remove the infection before death. An infected victim that is cured is also restored to their normal hit point maximum. There are rumors of random individuals that are naturally immune to the disease, though such tales also say that the immune are carriers, and unwittingly help the spread of the disease.

Rosen Doom

The disease known as rosen doom is identified by the haunting reddish hue that affected corpses take on. The blood of the deceased victims also remains a strange reddish color even decades after their death, partially preserving corpses, and retaining the virulence of the disease for just as long.

This disease is primarily spread through contact with infected blood, although any bodily fluid can transfer the disease. A creature that makes contact with such a fluid must make a DC 16 Constitution saving throw, becoming infected on a failure.

Symptoms develop within 1d4 days. Infected creatures suffer 1 level of exhaustion. While exhausted, the creature coughs blood and develops weeping sores across their body. At the end of each long rest, the creature must make a DC 16 Constitution saving throw, taking 11 (2d6) necrotic damage on a failure and gaining 1 level of exhaustion.

On a successful save, the DC of the saving throw is reduced by 1d4+1. When the saving throw DC becomes 0, the disease ends.

Shadowed Typhus

This magical illness infects a victim’s shadow, causing the victim to slowly become a dark shade.

This diseases may be contracted if an infected creature stands in your shadow, or by lurking in the same shadow as an infected creature. Creatures of the outsider and aberration type are immune to the effects of the disease, but may still carry and transmit the disease to others.

Symptoms develop the sunset after contraction.

At that time, the victim begins feeling weak, and their shadow appears darker than usual. The victim begins to fear any light and feels pain and anguish if exposed to sunlight (this exposure does not cause any physical harm). The creature must make a DC 15 Constitution check to willingly step into any bright light.

If allowed to linger in the shadows, the disease worsens, and the infected creature begins to look as though they are in the shadows even when in the light. After three days without exposure to any bright light, the creature begins a transformation into shadow that takes place from sunset to dawn after the third day of prolonged darkness. The infected creature becomes a shadow that is able to create other shadows through disease rather than by its strength drain ability (which otherwise remains unchanged).

The only cure for this disease is prolonged exposure to sunlight (1 uninterrupted hour), radiant damage (equal to half of maximum hit points), or a lesser restoration. Spells and abilities that remove curses or diseases will also end this disease.


A strange and unusual condition, telepathitis is transmitted by mental contact with an infected creature, or more rarely through physical contact with brain tissue. Such contact requires a DC 13 Constitution save if physical contact is made, or a DC 11 Wisdom save if mental contact is made. Failure results in infection.

A creature so infected can begin to read thoughts, but does so erratically, gleaning surface thoughts from any nearby creatures. Through mental strain, an infected creature can hone the ability and listen to specific thoughts, as per the spell detect thoughts. They can only use this ability once and regain the ability to do so after each long rest.

However, this and other mental stressors cause the disease to worsen, and they begin to deteriorate. An infected victim gains an exhaustion level each time they strain to use their ability to detect thoughts and gain an additional exhaustion level if they read the thoughts of a creature with an intelligence score of 18 or higher.

The infected creature also gains a level of exhaustion if they are around a crowd of 10 or more for more than a minute. With each level of exhaustion gained, the infected suffers from a headache of increasing intensity.

When the infected creature reaches 6 levels of exhaustion, their head explodes and they die. This can only be prevented by prolonged sensory deprivation and rest. The infected creature cannot have any levels of exhaustion nor be exposed to any thoughts for a minimum of 3 days. If such conditions are met, they are no longer infected.

Curiously, creatures that resemble brains are susceptible to this disease, which displays more as a wasting cancerous condition. Intellect devourers, grell, and brain consuming creatures are likely vectors for this disease, which sometimes mercifully thins their populations.

Terror Plague

Called by some the “rabid fear”, this disease attacks the mind and is spread through bodily fluids, most commonly by sweat. Victims begin to see hallucinations of their darkest fears, often attacking others and spreading infection in an addled attempt to fight off the visions of terror.

A victim exposed to the body fluids of an infected must make a DC 12 Constitution save or become infected.

Onset happens during the first evening of infection, and symptoms manifest as visions of dangerous and deadly creatures or hazards, or often the subject of the victim’s phobias or self-doubts. Once these visions begin, the victim sweats profusely, to the point that they drip with sweat. Infected creatures are unable to sleep or rest, and gain no benefits from a short or long rest other than staving off exhaustion. Prolonged infection might result in long-term madness (see madness rules).

One cure for this disease is to gouge one’s eyes out. Though not a popular cure, it can be a necessary one to stave off madness and sleep deprivation.

This does not so much cure the disease as it prevents the symptoms, and the victim can still transmit the disease to others (though they do not suffer from the heavy sweat that the visions induce). The only other non-magical cure must be procured from the blood of a hag and requires a DC 20 Wisdom (Medicine) check to properly distill into a working cure. Whatever the connection between hags and this disease may be, it only serves to make each all the more terrifying.

Section 15: Copyright Notice

5th Edition Horror. © 2018, Fat Goblin Games; Author: Ismael Alvarez