Anybody know how Unholy Aura works? The Walking Nightmare -- Edge of the Abyss, p. 87 -- has this trait, but I can't find the mechanics.

Same here!

Without any errata to hand, I think I will just assign some sort of Armour Points value to it. Although I do wonder whether it's supposed to work like a force field.

Good idea, thanks! Until the errata comes out, I'll treat it like a Terminator's "force field" - 35% chance of negating an attack, no chance of the field collapsing.

Cheers,

- V.

I sent this question in using the "Rules Question" link at the bottom. No word yet, but when they respond I'll put it here.