The Book of Breathings

A split text written in a language of salt and starlight that can nullify the Cauldron's power.

Also known as: The Breath and the Word, The Split Text, The Cauldron's Silence, The Book of the Making and Unmaking

What They Know

The Book was written in a language that predates the fae—a tongue of salt, starlight, and the sound of the Cauldron's turning—and only those who have been Made by the Cauldron can read it, which is why Feyre Archeron, remade from mortal to High Fae, is the only person in Prythian who can decipher it.
It was split in two after the last War: the mortal queens took one half, the fae High Lords the other, as part of the Treaty that bound the Wall. Neither side trusted the other with the whole, and so the Book has remained broken for five centuries.
The Book does not contain spells in the usual sense—it contains the language of the Cauldron's own making, the names of the things it Made and the words that can unmake them. To speak the words aloud is to invoke the Cauldron's power directly, and no one has dared do so since the War.
The King of Hybern has been searching for both halves of the Book for decades, knowing that with it he can command the Cauldron to tear down the Wall and enslave the mortal world again. He has already corrupted one mortal queen to obtain her half and is hunting the other.
The Book is bound by a powerful bargain: any who attempt to read it without being Made by the Cauldron will find their minds burned blank, their tongues turned to ash. This is why the High Lords have kept it locked away rather than study it.