Here’s one of the nastiest diseases an evil caster might want to inflict on their victims using the contagion spell. 

As found in the two most popular system reference documents, the contagion spell is woefully lacking in options for diseases. In Insults & Injuries, we presented optional rules for broadening contagion’s use by greatly expanding the range of diseases it could cause, but even these were, by necessity, incomplete. Some of the diseases which fit best with spells like contagion weren’t included in I&I, and so obviously couldn’t be included in the variant version of the spell, but fortunately, this space exists specifically for new material to be inserted. Here’s one of the nastiest diseases an evil spellcaster might want to inflict on their victims.

Necrotizing Fasciitis

Minimum caster level: 15

A creature magically afflicted with this disease immediately becomes Sickened. At this time, a Heal check (DC 14) performed on the affected creature will reveal that one of the creature’s limbs has developed a large, red, sore discoloration. In 1d4 hours, the creature becomes Nauseated; at this time the DC of the Heal check drops to 10. 1d20 hours later, the creature begins to make Fortitude saves (DC 15) each hour or suffers 1d6 points of Constitution damage; if the creature sustains two points or more, then one of these is instead a point of Constitution drain. The affected creature continues to sicken and rapidly dies unless promptly treated. A creature fights off the infection if they survive long enough to make at least one Fortitude save each day for two consecutive days. An infected creature has essentially no risk of transmitting the infection to another creature.

Necrotizing fasciitis is the famous “flesh-eating bacteria disease.” Necrotizing fasciitis is an extremely rare disease caused by a bacterial infection of the fascia, the connective tissue underlying the skin and coating the muscles. A number of different bacteria can cause the infection, but all have a similar mechanism of action: bacteria enter the deep tissues, often through a wound (which a creature may or may not be aware of), and begin producing enzymes and toxins which break down surrounding tissues. This digestion releases gasses between the tissue layers, causing swelling and “crepitus,” the ability to feel air bubbles under the skin (a sensation which has been likened, I kid you not, to the sensation of touching Rice Krispies under saran wrap). As bacterial toxins accumulate they trigger a systemic immune response, manifesting as fever, malaise, and general icky-ness, but the swelling, pain, and redness around the site of the actual infection is the most obvious symptom. In the disease isn’t treated, muscle breakdown can completely destroy a limb, although many creatures will die of systemic collapse before that can happen.

In nature, necrotizing primarily affects creatures with immune systems that have been compromised systemically, as in HIV, or in a specific part of the body, as with the reduced blood flow and damaged nerves seen in poorly-controlled diabetes. These diseases are presumably much less common in medieval fantasy than in our world, which only contributes to the disease’s rarity.

Whereas for us, treatment of necrotizing fasciitis is extremely difficult because it requires invasive surgery and high doses of (usually multiple and expensive) antibiotics, in a fantasy setting the disease is presumably wiped away by a single remove disease spell. Advanced cases may require restoration or even regeneration spells, but even this is fairly easy to obtain assuming a creature to access/afford it.

The naturally-occurring form of the disease isn’t terribly useful in-game because by all rights it should be phenomenally rare to the point of being unknown, and in any event, any society with magical healing can cure it so easily as to make it almost laughable. As a weapon, however, it has a good deal more potential. In addition to being an obvious and ideal choice for the contagion spell, it might be very thematically appropriate for undead or disease-themed creatures to be able to cause it through their attacks. Necrotizing fasciitis could be used as in-game flavour text for mummy rot and similar curses and afflictions, and the truth is that it isn’t that far off. However it gets used, necrotizing fasciitis can and should be a terrifying, deadly infection capable of knocking even a strong character off of his or her feet without rapid help. Naturally, it should also be used sparingly, but an antagonist who uses this as a signature spell or preferred means of execution may become a memorable figure in players’ minds. 

More than four years ago, Dr. Eris Lis, M.D., began writing a series of brilliant and informative posts on RPGs through the eyes of a medical professional, and this is the one that appeared here on December 5, 2015. Lis is a physician, gamer, and author of the Skirmisher Publishing LLC OGL sourcebook Insults & Injuries, which is also available for the Pathfinder RPG system.