The Suns of Scorpio — Alan Burt Akers

The second book of the Dray Prescot series.

Slave of the colossus builders or scourge of the Inland Sea?

Both roles awaited Dray Prescot on his return to Kregen. Torn between two contending forces, the Star Lords and the Savanti, Prescot himself wanted only to find his beloved, the Princess Delia of the Blue Mountains. But the powers that had drawn him across interstellar space to the world that orbited the red and green suns in the Constellation Scorpio had set him a task, the nature of which even he could not fully comprehend...