Being released August 11, Emerald Warrior is the newest series to take on the Green Lanterns.  From the DC Source blog:

A whole new chapter in the epic GREEN LANTERN saga gets under way as Guy Gardner begins his secret mission for Atrocitus, bringing him into conflict with Hal Jordan with massive repercussions for the Green Lantern Corps.

Guy takes fellow Emerald Warriors Kilowog and Arisia along as he explores the Unknown Sectors — but what happens when they discover his mission and what’s waiting for them in the unpatrolled darkness?