From a widespread plague to the bite of a dire rat, disease is a serious threat to common folk and adventurers alike. Diseases rarely have a limited frequency, but most have a lengthy onset time. This onset time can also be variable. Most diseases can be cured by a number of consecutive saving throws or by spells such as remove disease.
Note: Not everything listed here is a true "disease" as some of the below are more accurately described as infections, parasites, or other unfortunate maladies adventurers might occasionally have to cope with.
While standard diseases challenge players and make for good storytelling opportunities, they are typically telegraphed days in advance with the first Fortitude save and easily cured with low-level spells. Further, very few diseases are even capable of killing, and often they do nothing more alarming than dealing ability score damage. However, there are worse diseases brewing in the world. This section contains new options for diseases, including a collection of templates that can be applied to any disease to make it more frightening in a variety of ways, and a selection of new diseases that progress through a series of horrifying symptoms.
Not all strains of the same disease are identical. Diseases mutate and change over time, so the PCs may encounter local strains of devil chills, filth fever, and other diseases that are different from those with which they’re familiar.
These different strains might be particularly fast-acting, easier to spread, resistant to treatment, or otherwise improved over the default version of the disease. The following section presents several templates that can be applied to any disease to represent more dangerous strains.
These templates function similarly to creature templates, and several templates can be applied to the same disease to create a truly horrifying plague. The special properties of a disease with a template are difficult to predict without special training. Unless a character spends at least an hour examining the disease and its victims and then succeeds at a Heal check (DC = the disease’s save DC + 10), she identifies the disease as its more common variant, without realizing the differences.
An incurable disease is all but impossible to cure completely, even with the aid of magic. The incurable template can be added to any disease. The disease retains its base statistics except as noted below.
Save The disease’s saving throw DC is reduced by 5.
Cure The disease cannot be cured with any number of successful saving throws. Whenever the afflicted creature succeeds at a saving throw to resist the disease’s effects by 5 or more, you automatically succeed at your next saving throw against the disease’s effects as well. Even spells that can normally cure diseases only cause the disease to become dormant for 2d4 days, after which the affected creature must begin attempting saving throws to resist the disease’s effects once more.
A lethal disease attacks the host’s body with ruthless efficiency.
Save With each failed saving throw, the DC of any future saves by the affected creature to resist the disease’s effects increase by 1. These increases stack to a maximum of 5.
A lingering disease is one that tends to remain with its victims for a long time and is difficult to cure completely. The lingering template can be added to any disease. The disease retains its base statistics except as noted below.
Save The disease’s saving throw DC increases by 2.
Any ability score damage or drain dealt by the disease is reduced by 1 (to a minimum of 1).
Cure The number of consecutive successful saving throws required for the victim to be cured of the disease increases to double the normal amount.
Special Any effect that would cause a creature suffering from the disease to be cured of it (including remove disease) instead counts as a single successful save for the purposes of curing the disease through consecutive saving throws. No more than 1 successful save can be accrued in this way within a single period of the disease’s frequency (1 day, for most diseases), even if multiple effects would cure the creature of its disease.
Finally, even if a creature is completely cured of the disease, small amounts of it remain within its system, and there is a 30% chance per day that the creature becomes reinfected, and must succeed at a new saving throw or contract the disease again. This chance decreases by 5% per day, until it reaches 0%.
A magic-resistant disease is protected against magical treatment.
Sometimes this is because the disease has a magical origin or has been infused with magic, and sometimes it’s because the organisms that cause the disease simply react differently to magic than most infectious organisms do. The magic-resistant template can be added to any disease. The disease retains its base statistics except as noted below.
Save The disease can affect creatures that have Constitution scores and are normally immune to disease, whether that immunity comes from a racial trait, class feature, spell, magic item, or other source. However, such creatures receive a +4 bonus on saving throws when attempting to resist the disease’s effects.
Cure The disease is particularly difficult to remove using magic.
Special The disease responds violently to any attempts to heal it using magic. Whenever the diseased creature is subject to a spell or ability that cures diseases, it must succeed at a Fortitude save or suffer the disease’s effect. This does not reset the disease’s frequency, and succeeding at this check does not count toward the number of consecutive saves required to be cured of the disease.
A plague is a disease that spreads very effectively, and can easily pass through an entire community in a short period of time. If left unchecked, plagues can ravage entire cities or regions, and in the case of particularly deadly or virulent plagues, can potentially even bring an end to mighty civilizations. The plague template can be added to any disease. The disease retains its base statistics except as noted below.
Type If the disease’s type is ingested, it instead changes to inhaled. If its type is injury, it instead changes to contact. If its type is contact or inhaled, it remains the same.
Special Simple contact with or, in the case of inhaled diseases, spending time near a creature infected with a plague can expose others to the disease. If the plague is an inhaled disease, then a creature afflicted with the disease creates an aura of disease around it. Any coughing, sneezing, and in some cases, even breathing releases clouds of disease-causing organisms into the air. Any creature that comes within 30 feet of the 147 diseased creature is exposed to the plague, and must succeed at a Fortitude save or begin suffering its effects. A potential victim must attempt a new save each time it moves within 30 feet of a diseased creature, to a maximum of one saving throw every 10 minutes. Any creatures that remains within 30 feet of the diseased creature must attempt a new saving throw every 10 minutes. If the plague is a contact disease, each time a creature touches the diseased creature, or touches an object that was touched by the diseased creature in the last 24 hours, the potential victim is exposed to the plague, and must succeed at a Fortitude save or begin suffering its effects.
A ravaging disease is one whose effects are particularly difficult to heal, and that can permanently scar creatures affected by it.
If the disease deals ability damage, each time the affected creature fails a saving throw to resist the disease’s effects by 5 or more, 1 point of that ability score damage becomes permanent ability score drain instead. If the affected creature rolls a natural 1 on a saving throw to resist the disease’s effects, all of the ability score damage becomes permanent ability score drain.
Cure The number of consecutive successful saves required to be cured of the disease increases by 1.
Special Ability score damage and drain dealt by the disease cannot be healed as long as the affected creature is still infected by the disease. This applies both to natural healing and magical healing (such as lesser restoration).
A virulent disease is particularly fast-acting, and runs its course in hours, rather than days. While this could mean the disease runs its course more quickly, leaving the victim disease-free, virulent diseases are particularly taxing on their victims and often end in death. The virulent template can be added to any disease. The disease retains its base statistics except as noted below.
Onset If the disease’s onset is normally measured in weeks, it is instead measured in days. If it is normally measured in days, it is measured in hours. If it is normally measured in hours, it is measured in minutes.
Frequency If the disease’s frequency is normally measured in weeks, it is instead measured in days. If it is normally measured in days, it is instead measured in hours. If it is normally measured in hours, it is instead measured in minutes.
If the disease doesn’t already deal Constitution damage on a failed save, it deals 1 point of Constitution damage in addition to its normal effect on each failed save. If it normally deals Constitution damage, increase the Constitution damage by 1.
Special If the diseased creature fails two consecutive saving throws, it is sickened until the next time it succeeds at a saving throw to resist the disease’s effects. If the diseased creature fails four consecutive saving throws, it is nauseated until the next time it succeeds at a saving throw to resist the disease’s effects. These penalties are in addition to any other effects of the disease, and cannot be removed as long as the creature remains diseased. Even if the creature is normally immune to the sickened or nauseated condition, that condition still applies; only immunity to diseases protects against gaining the condition from a virulent disease.