Rating: WORTHY!
This final volume sees the retreat from the continent of Canea which has been overrun by the Vord. Gaius Octavian ("Tavi") along with the illustrious Kitai and the Canim leader Varg only to discover that Alera has been largely overrun as well. Having made landfall in the north, the group must strike east to link up with the remaining Aleran resistance in Riva.
The Vord queen, now an accomplished water crafter offers a surrender to any and every Aleran. They will be allowed to live out the remainder of their life in peace provided they vow to have no children. Tavi uses the same method to announce his return and his defiance of the Vord. In response, the Queen kidnaps Tavi's mom, Isana, as well as Fade, aka Araris Valerian, Isana's boyfriend.
With the help of the now friendly Ice People of the north, and a strong wind provided by Alera herself, Tavi sails over the ice, but Riva falls to the Vord, and led by acting First Lord Aquitainus the survivors retreat, of course, to the Calderon valley, much in the way the final showdown in the Potter stories was in Hogwarts. Tavi's uncle Bernard and his wife Amara meanwhile have been fortifying the Calderon. Aquitainus dies trying to beat the joined forces of his wife and the Vord queen.
Tavi launches an assault on Riva when he arrives there, bringing down the city walls like Joshua purportedly did, and his fire crafters torch all Vord food supplies. He then moves on to the Calderon where he hopes to pin the Vord between his forces and the rest who occupy the valley's defenders. The Vord queen raids Tavi's camp and wounds him.
It's at this point that Invidia switches sides again and betrays the troop positions of the Vord, but her betrayal was predicted by the Vord queen, so when all of the Aleran high nobles use their various crafting to attack the queen she slaughters many of the attackers. Invidia once again tries to switch sides, but Amara kills her. When the Vord queen retreats, she leaves behind Isana and Araris who are now free.
Tavi and Kitai pursue the escaping queen in an attempt to stop her from calling on the wild and powerful mountain furies. At the same time, the Vord launch an attack in the Calderon and begin to slowly overwhelm the defenders, but Tavi and Kitai actually beat the Vord queen and kill her. Since she is the hive leader, this results in the rest of the Vord becoming directionless and uncoordinated. In effect, they're beaten.
With Aquitainus conveniently out of the way now, Tavi rightfully becomes the First Lord and he and Kitai finally marry. Despite the possibility of a sequel, with other, though lesser Vord queens still at large on the Canea continent, Butcher never did revisit this series. I didn't expect him to, but for me these books would make a wonderful film series. For reasons which escape me, no one has ever seemed interested in making them. Maybe Netflix will try it? They did The Witcher, and this is in many ways a similar sort of fantasy. We can hope! Meanwhile I declare this a worthy read and commend the whole series - one of the very few series I've been able to stand to read.