More Than Just The Sniffles
TLDR: The rules around diseases change when it comes to a Named Disease. Class features, spells, etc, that provide immunity to, or instantly cure a regular disease work a bit differently depending on how severe the Named Disease is.
Diseases In D&D
While there are rules around diseases in D&D, they’re a somewhat underwhelming mechanic, and often find themselves being hand-waved away at most tables. This makes certain spells – like Lesser Restoration – and class features – thinking Paladin and Monk – less effective overall. What’s the point of being immune to diseases if no one in your party was going to get sick anyway? This is where Named Diseases come in.
Named Diseases (NDs)
There are 15 Named Diseases (NDs) in the Theria Setting Book, each with their own specific rules on how to cure them. The Diseases chapter goes over the setting-specific diseases, how they are contracted, how they progress through various stages, and how they’re treated or cured.
They range in severity, from level 1 to 5, with level 1 being the easiest to treat and cure. A Lesser Restoration spell, for example, will cure a level 1 ND like Flop Sweats instantly. The same spell instead provides advantage on Con Saves for a level 2 ND like The Snickers, and will have no effect at all on a level 4 disease like Sloth Fever.
Non-Named Diseases (NNDs)
NDs range in severity from level 1 to 5. A non-named disease (NND) can be thought of as a level 0 disease, and would include all the basic and generic diseases that come standard with D&D. They still exist and are in the world, but they either have less of an impact on a person than a level 1 ND, or they run their course so quickly that it’s more akin to having an off day than anything else.
Mechanical Adaptations
The Treatment Rules for NDs (p.180 of the Setting Book) supersede the rules on Lesser Restoration and similar spells. Refer to those rules when NDs are involved.
Class, race, and most item effects/features follow the logic of Lesser Restoration in the ND Treatment rules.
- Level 1 Diseases – No changes, feature works as described.
- Level 2 Diseases – The spell/feature/ability allows the target to roll a Con Saving Throw with advantage immediately with hope of reversing the disease progression, and grants advantage on future checks associated with the curing or otherwise overcoming the disease.
- Level 3 Diseases – The spell/feature/ability allows the target to roll a Con Saving Throw with a +2 bonus immediately with the hope of reversing the disease progression, and grants a +2 bonus on future checks associated with curing or otherwise overcoming the disease.
- Level 4 & 5 Diseases – No effect. These diseases are too strong on their own, so more powerful magics and treatments are going to be needed.
Example – Paladins become immune to diseases at level 3 through a class feature, according to the PHB. By applying these mechanical changes, a level 3 Paladin would be immune to all NNDs and level 1 NDs, have advantage on checks for level 2 NDs, and a +2 bonus to checks for level 3 NDs.