Custom reaction? Invoke Reckoning

[nimrodx]

Age of Ashes has an NPC with a reaction called the above.

You cannot select this reaction as an ability when creating this npc.

How do you add custom abilities such as this..

Invoke Reckoning [reaction] (divine, enchantment, mental)
Trigger The skeletal Hellknight hits a foe with a Strike.

Effect The skeletal Hellknight causes the creature
struck to endure the pain of an Order of the Nail’s
reckoning—a rite of mortification Hellknights of that
order use to focus their minds. The creature struck
feels as if nails are being driven into their body, and
must succeed at a DC 17 Will save or be stunned 1
from the pain. On a critical failure, the pain manifests
as actual puncture wounds, dealing an additional 2d6
points of piercing damage to the victim.

...or is it not possible?

 

[mototom]

Create it as a basic or detailed NPC. Use the Custom NPC for the ancestry. Then under Customize Ancestry the last section will be New Abilities (Unique to this ancestry).

You can define the title, the text, the type of action, what section of the stat block it belongs to, traits, etc.

 

[Ras_Nsi]

You can a custom action, and what type of action it is (reaction) easily enough. But no where on the action's page does it have a field to define what the trigger for the reaction is.

Wer're asking for an entry like this:

where the trigger is formated the same and the traits are easily accessable, unlike what you currently have to do:

On that note, It would be amazing to abe able to create custom abilities that aren't just attacks, but specify what happens on crit. success, success, failure and crit failure individually, so it looked less like:

and more like a spell entry: