Disease is a source of threat in fantasy worlds, either from fantastic diseases that ravage the land from time to time or those caused by Disease Spirits.

Every type of disease has the following information detailed:

Name: The disease’s name.  Also, if the disease is magical, it will be mentioned here.

Type: Lists whether the disease is spread through contamination, touch or is airborne.

Delay: The time between the disease’s introduction to a character, to the time its effect takes hold. It is also the time following disease contraction that a victim will make follow-up opposed disease tests.

Potency: This is a number between 10 and 100 that measures the strength of a disease. Some magical diseases, like the shining plague, have even higher Potencies. A character must make an opposed Resilience test versus the disease’s Potency test to avoid or mitigate the damage of the disease.

Effect: Usually hit point damage, though this is not universal. Many diseases will apply a penalty to Characteristics or skills. More exotic diseases may cause hallucinogenic effects, paralysis or a combination of effects. These take place after the delay noted above.

The effects of the disease cannot be removed or healed until the disease itself has been neutralised or has dissipated in the victim’s system.

Disease Succeeds, Character Fails

If the disease succeeds its Potency test, and the character fails their Resilience test, the disease has its full effect.

Character Succeeds, Disease Fails

If the character succeeds their Resilience test, and the disease fails its Potency test, the disease does not affect the character.

Both Disease and Character Succeed

Whoever rolled the highest in their test wins.

Both Disease and Character Fail

Whoever rolled the lowest in their test wins.

Unlike a poison, diseases will progress if a character does not resist its effects. Once the victim fails the first opposed test, they will have to make an additional opposed test (after an amount of time determined by the disease’s delay statistic).

If the victim succeeds this second opposed test, they have overcome the worst of the disease and will no longer suffer its effects, other than remaining hit point damage, after a while. Use the disease’s delay statistic to determine how long this takes.

If the victim fails this second opposed test, they fall deeper into the disease. Apply all of the disease’s effects again to the character. Once the delay period has elapsed once more, the victim will have to make a third opposed disease test, and so on.

Here are two examples of diseases, one a normal mundane disease and one that is magical.

Example Disease

Name:  The Shakes

Type: Touch

Delay: 1-2 days

Potency: 50

Effect: This flu-like disease renders its victims in a cold and constantly shaking state, during which DEX halved. Also, for each day that the victim suffers from the Shakes, they take 1D6 hit points of damage.