Preach was a terran who lived in the Gutter, employed by the crime lord Fagin, though answered to his lieutenant Markus Ralian.
Fagin called his followers to defend his HQ from Nova. Ralian assigned Preach, along with Diva and Seer, to round up hab addicts for the defense.
DeCandido, Keith R. A. (November 28, 2006). StarCraft: Ghost: Nova. Simon & Schuster (Pocket Star). ISBN 0-7434-7134-2