The Book of Breathings
A spoiler-free guide to A Court of Thorns and Roses (ACOTAR).
Only showing what’s been revealed up to your current progress. Future events, identities, and relationships are hidden.
Overview
The Book of Breathings is an ancient magical artifact forged from the last molten ore used to make the Cauldron. After the War, it was divided into two separately guarded halves.
The Book possesses awareness and a voice of its own, addressing those around it and responding to their identities, intentions, and deceptions.
When its halves are finally joined, the Book becomes strong enough for Feyre to use against the Cauldron. In that state it turns her into a conduit directly linked to the Cauldron rather than acting as a passive text.
After the Cauldron is broken, Feyre tries to use the Book again but cannot read its engraved symbols well enough without Amren. She throws it into the void inside the Cauldron, and it vanishes without visible effect.
Appearance
Summer's half is housed in a small lead box. The Book itself consists of dark metal plates bound by three rings of gold, silver, and bronze, with its text engraved in the ancient alphabet of the Leshon Hakodesh.
Ownership or Custody
One half of the Book is held by the Summer Court under blood-spells keyed to its High Lord. The other belongs to the human queens and is protected against faerie theft or magical coercion.
After the Night Court steals Summer's half, Amren takes custody of it in Velaris for study. Rhys intends to leave it with her as long as her work requires, despite the resulting conflict with Summer.
A mortal queen secretly relinquishes the second half during an audience with the Night Court. It is carried to Velaris and placed in Amren's hands, giving her both portions of the Book.
Once the halves are restored to each other, Amren keeps the complete Book in her loft and continues working with it.
Function, Rules, and Limitations
The Book contains spells capable of negating the Cauldron's power or controlling it completely. Only a being who has been Made can truly wield those spells.
The human queens' half is warded so that faerie theft or magical trickery would melt it back into ore unless a mortal queen gives it freely.
The warded box containing Summer's half opens for Feyre only after recognizing her as Made and Unmade and acknowledging the combination of powers she carries. The Book's presence can suppress nearby magic, and its painfully cold container does not render it passive or harmless.
Rhys warns that the queens' half may also refuse transfer if too much scheming or deceit undermines the requirement that it be given freely.
Amren decodes a procedure for nullifying the Cauldron that requires Feyre to touch it while speaking the Book's written spell. Bringing the two halves physically together releases an immense, detectable surge capable of alerting Hybern and awakening older powers.
The separated halves lack the strength to overcome the Cauldron, so effective use of the nullification spell requires joining them despite the resulting surge. Once united during the attempt, the Book makes Feyre a conduit linked directly to the Cauldron rather than functioning as a passive collection of instructions.
The nullification spell was capable of working, but completing it was killing Feyre; releasing it before completion caused her attempt to fail.
A separate answer in the Book is an unbinding spell that can use the Cauldron's power to release Amren into her original form.
Without Amren, the Book's engraved symbols cannot be interpreted well enough to repair the damaged Cauldron, sharply limiting its practical use even for Feyre.
Important Uses
Feyre joins the Book's halves and invokes its spell against the Cauldron, entering a conduit state linked directly to its power.
At the final battle, Amren brings the Book to the Cauldron but discards the stated anti-Hybern plan. Its actual spell allows her to unbind herself and assume her original form through the Cauldron's power.
While trying to repair the broken Cauldron, Feyre throws the unreadable Book into the void within it. The artifact vanishes without producing any visible effect.