Monarchs and commoners, heroes and villains, and creatures of all makes across all planes of existence in all states of life (or unlife) can be susceptible to the effects of an overactive immune system. All it takes is an errant mote of dander, a puff of pollen, or the wrong substance ingested, and your entire day can be ruined.
This 5e homebrew supplement describes how to assign an allergen to your character, and how it manifests mechanically within the game.
- Chapter 1: Roll for Allergen
- Chapter 2: Allergic Reactions
- Chapter 3: Treating Allergies
- Chapter 4: Variant Rules
- License
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This content was written to be compatible with Dungeons & Dragons 5th Edition.
This document makes the following modifications from SRD 5.1 and SRD 5.2:
- This document uses new traits called Condition Resistance and Condition Vulnerability. Resistance to a condition means that a creature has Advantage on saving throws made to resist that condition, and vulnerability to a condition means that a creature has Disadvantage on such saving throws.
- Damage and condition resistance, vulnerability, and immunity are now grouped together as Resistances, Vulnerabilities, and Immunities respectively.
- Resistance, vulnerability, and immunity to Poison apply to both the damage type and the Poisoned condition.
Allergies is © 2023 Mario Panighetti. This work is licensed via CC BY-NC-SA 4.0.
System Reference Document 5.1 ("SRD 5.1") © 2016 Wizards of the Coast LLC. Licensed under CC BY 4.0.
System Reference Document 5.2 ("SRD 5.2") © 2025 Wizards of the Coast LLC. Licensed under CC BY 4.0.
The materials below are referenced under fair use exemption of the U.S. Copyright Law and are restricted from further use. These materials, including references to game mechanics, are not approved or endorsed by the copyright holders and do not constitute any license or agreement with the copyright holders.
Player's Handbook (2014) © 2014 Wizards of the Coast LLC.
Wild Magic Effects Table by amiplayingright.