In The Emperor's Wake
Ayita's Spell Books
A spell book in the Cheyenne Language
This spell book was hand written by Ayita, and judging from the quality of the material, it looks to be fairly recent. The book is written in Cheyenne and it details how she managed her Biomancy rituals that allowed her to shapechange. There are notes on an item of power she had been working on creating that would make the shape changing an at will process, unfortunately, that was buried with her along with all of her other magic items.