Yancy Gray was a marine raised on Tarsonis. He was known for not knowing when to keep quiet. Gray served under Lieutenant Arcturus Mengsk in Dominion section. In August 2480, a period when he and the rest of the section were supposed to be on leave, Gray got his first taste of action on the world of Sonyan, forcibly removing Kel-Morian miners from Turanga Canyon, Gray performing a flanking maneuver alongside fellow section members Chuck Horner and Toby Mercurio.