The story begins with a flashback to a year earlier, detailing the war between New Genesis and Apokolips mentioned in JLA: The Nail. The consequences of this war threaten to destroy millions of lives on adjacent planets, and the Green Lantern Corps is summoned to stem the loss of life. One of their number is killed, and the power ring selects Big Barda as its new host. Using the ring in combination with a Mother Box, Barda and Mr. Miracle (who had transferred his consciousness to Barda's armor circuitry from his dying body) shut down a destructive device designed to vaporize all matter within millions of light years of the war. The flashback was shown by Green Lantern (Hal Jordan), who reveals to the rest of the JLA that the Central Power Battery on Oa is weakening. The Guardians of the Un