Here Be Dragons - Alliance, #4

From childhood they were bred as warriors. They win. They defeat. Now Tucker Thompson has been sent to shut them down, with or without a fight. Thunder rolls through the Australian Outback as Thompson faces an enemy wielding fire, ripping through chains, and showing no mercy for the human spirit. While Thompson has no memory of Australia, he spent six years there. Now as a sergeant in the Alliance Military Guard, he dominates on the field, but doesn't always know why.
Even with strikes on his record, his abilities as a loyal soldier are an incredible asset, but convincing the Army Ranger team led by the feisty Captain Cheri Skye proves to be an entirely different kind of battle.?When the Guard's motives come into question with a global audience watching, Tucker is left wondering what exactly he's fighting for and how he will lead his crew into the Outback to chase the shadows of his past.