5e - Condition Immunity

[Vaall]

Condition Immunity for 5E
Current Version: v1.0.2 • Updated: 2026‑06-22

https://forge.fantasygrounds.com/shop/items/2822/view

Condition Immunity blocks any effect that tries to apply a condition to a creature that is immune to it. If a target is immune, the effect is fully dropped and never added to the Combat Tracker. The extension displays a short chat message explaining why the effect was blocked.


Full effect drop: conditions that the creature is immune to are never applied.



A note from the author
This extension was originally part of a larger, personal script tailored to the way I run games and manage effects in Fantasy Grounds. I'm now separating that project into smaller, focused features (with more to come). I'm sharing this one early in case it proves useful to others as well.


What it does
When an effect is applied (e.g. Poisoned, Paralyzed, Frightened), the extension:


Checks multiple immunity sources:
- Active effect labels (e.g. IMMUNE: poisoned, blinded)
- 5E sheet data (e.g. the conditionimmunities field, traits, actions)
If a matching condition immunity is found, the effect is not added at all (full drop).
If no immunity matches, the effect behaves normally.


Supported Conditions
The extension recognizes all core 5E SRD conditions:

Blinded · Charmed · Deafened · Frightened · Grappled · Incapacitated · Invisible · Paralyzed · Petrified · Poisoned · Prone · Restrained · Stunned · Unconscious


Changelog

v1.0.2 — Correction to make the extension work without the BCE
v1.0.1 — Fixed extension when an NPC has an "IMMMUNE:" effect + BCEG compatibility
v1.0.0 — Initial public release.


If you try it, feedback and edge cases are highly appreciated!
Contributions are welcome — especially for compatibility reports, additional immunity sources.

Vaall

[Zacchaeus]

The ruleset does this by default does it not. Or am I missing something.

[Vaall]

If I'm not mistaken, the default ruleset will simply remove the sentence containing the immunity.

If I apply the effect "poison very strong; poisoned; unconscious" to a target immune to the poisoned state, the effect applied will be "poison very strong; unconscious".

With this extension, nothing will be applied to the target because it blocks the entire effect.

I'm no longer at my computer to verify 100% that the native FGU ruleset allows blocking the entire effect.

If that's the case, I'll remove the extension from the forge as soon as possible.

[Zacchaeus]

Yeah, you could be right about that. I’ve only seen it be effective if you apply a condition such as poisoned on its own. It probably will leave anything that isn’t specifically a condition. I misunderstood what the purpose of your extension was.

[Moon Wizard]

Yes, it only blocks part of the effect; because we can't always assume that effect components are tied together. So, it only drops the fully immune part; but it is built into 5E.

Regards,
JPG