From ROI Wiki

Sine is the executive officer to Rom, commander of the Guardians and a creation of Dr. Slao to help him in his fight against the Margog and the Horde, of which they are successful. Upon Rom's death he takes over command of the last remaining remnant of the Guarians, as well as his two friends, Ver-mach and Ick-pok. Eventually the last of the Guardians die, leaving just Sine, Ver-mach and Ick-pok as the last of Slao's army. They in turn join with the Burgon Lions and help them in defending the Yigzan people wherever they, and their exceptionally unique skills, are needed.