From Creatures Wikia
The Ghost/Phantom Norns are a new breed variant by Marcus Kurzbac, created as part of the "Creatures-the Next Generation" project. This is a subspecies which occurs in several standard breeds, and thus occupies no special breed slot of its own.
- The Ghost/Phantom Norns all possess a mutation which (when combined with Marcus' Invisibility Agent) gives them the ability to become invisible whenever scared. They return to being visible when they calm down, or when they've been tickled.
The Ghost/Phantom norns are available for download at the CNG website.