Martha Wells 
Stories of the Raksura [EPUB ebook] 
The Falling World

In ‘;The Falling World, ‘ Jade, sister queen of the Indigo Cloud Court, has traveled with Chime and Balm to another Raksuran court. When she fails to return, her consort, Moon, along with Stone and a party of warriors and hunters, must track them down. Finding them turns out to be the easy part; freeing them from an ancient trap hidden in the depths of the Reaches is much more difficult.