All Down But Nine (Lingua achats Magika) by Ross, Kat NEUF

Lee Merriweather has fled across the line into Pedro Bragas jurisdiction, an untamed desert too vast for even the ruthless Guardia Territorial to keep any semblance of order. The Carnarvons want him dead or alive - and with Lees attitude, the first seems most likely.

The trail south runs straight through two thousand miles of badlands. To find him, Ruth and Sebastian must survive sabotage, bloodthirsty bandits, and fresh horrors at the Reverend Jollys church in New Jerusalem. The hardships draw them into a passionate affair, but loyalties are put to the test when they finally reach the capital of Aguadulce and all hell breaks loose. Ruth has privately vowed to stop Sebastian from killing Lee, even as the young savant seems bent on his own destruction.

And hes just a pawn in a game with higher stakes than anyone realizes. One that goes beyond empires. One that encompasses worlds.The phantoms are the key. But can Ruth uncover the truth in time to save them all?