Disease is a big part of what makes the Dung Age conceptualisation of the Middle Ages such a rich vein of inspiration for me. The Forgotten Realms, where I played most of my teenage D&D, seemed to be an anodyne place, bereft of all the sickness, madness and brutality of the historical accounts of the mediaeval period I had read. I want to create a setting that is grimmer and darker and consequently much more fun.
Commonly encountered in the Vermin-pits of the Middenmurk, miasma is “bad air” that causes disease, a manifestation of pure corruption that issues forth from the Middenmurk to plague the unhappy world, bringing suffering and misery. Miasmata appear as hazy patches of air and as a sense of foreboding and the stench of decay, i.e. players should probably have some warning of their presence. They tend to drift along slowly on currents of foul air or lurk in particularly noisome areas.
Vitruvius on miasma, 1st Century AD;
"For when the morning breezes blow toward the town at sunrise, if they bring with them mist from marshes and, mingled with the mist, the poisonous breath of creatures of the marshes to be wafted into the bodies of the inhabitants, they will make the site unhealthy."
Fanatics (clerics) are able to cleanse miasma (as did Abaris the Hyperborean as mentioned in this Wikipedia article), doing so requires a turn undead check as against wights.
Having a nosegay of posies or marjoram will grant a character a +1 to their save.
Miasma Table
Roll 1d8 to determine what manner of contagion the miasma carries.
1. Ague: Fever, sweating, cramps, headache. Save vs. poison or lose 1d3 points of constitution per day and suffer -2 penalty to actions for 1d8 days, after which constitution returns at one point per day.
2. Dropsy: Swelling of the brain causing stupor and confusion. Save vs. poison or spell-casting and other tasks requiring concentration (such as finding secret doors) fail unless a wisdom check is successful. Duration: 2d6 days.
3. Flux: Diarrhoea, vomiting, cramps. Save vs. poison each day or lose a point of constitution. Three consecutive saves indicates recovery.
4. Grippe: Fever, mucus, lethargy. Save vs. poison or lose 1 point from intelligence, strength, constitution and charisma. Save again each day to recover.
5. Horrors: Hallucinations and shakes. Save vs. poison or lose 1d4 wisdom and dexterity. A wisdom check is necessary each time an action is attempted, failure indicates inability to perform task due to confusion. Duration: 1d6 days.
6. Palsy: Shakes and partial paralysis. Save vs. poison or lose 1d8 dexterity. Duration: 1d6 days.
7. Consumption: Coughing up blood, fatigue, fever. Save vs. poison or lose 1d3 points of strength and constitution per week unless subsequent save is made. Duration: 1d6 weeks.
8. Pox: Painful lesions, cramps, fever. Save vs. Poison or lose 1 hit point per day, and loss of 1d6 points of Charisma, one point of which is permanent. Duration: 2d8 days.
I'll figure a way of working them into some kind of encounter table at some stage.
