A beautifully vicious tale about vengeance, vulnerability, friendship, and the more brutal aspects of nature. I loved the complex relationship between Ester and her roc, Zahra, and I quite enjoyed Ester's straightforward and savagely honest narrative (almost like a cynical version of How To Train Your Dragon where beast and man's partnership is driven by mutual benefit rather than unconditional loyalty). Untethered Sky gives the satisfaction of a full-length novel in half the time. I highly recommend it.