"It's A Dirty Job, But...!"
Hal Jordan has resigned his Green Lantern post, just as Major Disaster arrives in town. John Stewart shows up to face Disaster, but is told to bring the "real" Green Lantern, or the city will die a horrible death.
"Green Lantern Corps: I, Lantern"
Yron of Grendan needs to be the sector's chosen Green Lantern replacement so badly, he hijacks a ride to Oa to demand it.