- "Only a very few of their kind were allowed to assist in the writing of the Book of Shadows, that tells of the Nightsisters future glories among the heavens."
- ―Llarn Kristovv
When she founded the Nightsisters of Dathomir, Mother Gethzerion told her flock that the Book of Law, the moral guide of the original Witches of Dathomir, had been created after Allya had become old and weak. To replace it, Gethzerion began writing her own volume of learning, known as the Book of Shadows. It contained details on the spells and rituals she had created for the Nightsisters.
At the time of the Clone Wars, Talzin, a Shaman of the Nightsisters, alleged the Book of Shadows was in fact a restored version of Allya's original teachings. According to her, the writings of Allya didn't include the notions of "good" and "evil", and the Book of Law was a forgery written by Sisters who had been "weakened by the Jedi blood in their veins".
- Cracken's Threat Dossier (First mentioned)
- The Dark Side Sourcebook
- Jedi Academy Training Manual
- "Everything You Always Wanted to Know about the Nightsisters but Were Afraid to Ask"—Star Wars Insider 122
- Book of Sith: Secrets from the Dark Side