Where to find Lamashtu's mark?

[Dryder]

Spoiler:

Nualia's statblock show's one of her feats being Lamashtu's Mark. But I can't find the source of it, and it is not explained what it does. Can someone please point me to where I can find a description of that feat?

[Trace Coburn]

Page 56 of Adventure Path #1 in the 3.5 version; if you've got the Anniversary Edition, check out the New Rules appendix, p.419.

[Dryder]

p. 419 in the Book itself...
Sorry...

[Dryder]

Thx, Trace! Your post didn't show up until now.
Yes, a page reference in the RotRLAE would've been easier.