Green Lantern (1960) #200
"Five Billion Years" is written by Steve Englehart and drawn by Joe Staton and Bruce Patterson. Cover by Walt Simonson. Five billion years: that's how long the Guardians of the Universe have stood watch over the universe, protecting it from cosmic threats first through the android Manhunters and then through the heroic Green Lantern Corps. Now, the Guardians have decided it's time to tend to the further development of their own species as Oans. That means a reconciliation, although at first a violent one, with the females of their race, the warlike Zamarons.
That also means turning over the task of guarding the universe to their vast Green Lantern Corps. They aim to put the massive emerald Power Battery on automatic and allow their intergalactic police force to run their own affairs. For villains like Sinestro, the Weaponers of Qward, Star Sapphire and the hot-headed Green Lantern Guy Gardner that presents a golden opportunity to strike against their perceived "oppressors". And for heroes like Hal Jordan, John Stewart, Katma Tui and Arisia that means great danger as the historic transition of power occurs right before their eyes.