Star Crusader: Operation Hellfire. Star Crusader, #3

Nate had never expected to see a real war, but that was a month ago. Back when he'd been a videogamer with dreams of space combat. Now he was a pilot in Knighthawk Squadron, and in the middle of a violent warzone. The Star Empire and its vast legions are utterly committed to the elimination of the shattered Byotai Empire. They are ruthless, and ambitious beyond measure. As the terror spreads, millions of loyalists flee to the borders, desperate to avoid the violence while pursued by ruthless militias bent on destruction and enslavement.
There is a faint glimmer of hope for the Empire, and it takes the shape of the fifteen ships of the Orion Battlegroup. Safely hidden inside this fleet is the sole survivor of the Byotai Royalty, and with him, the only chance of peace in the region. With time running out, Admiral Churchill and his officers hatch an audacious plan. It is a plan that could allow them to escape the clutches of the Star Empire, and rally all remaining loyalists to this last prince.
If they fail, nothing will stop the spread of the insidious new enemy its quest for total domination.