Green Lantern was a fighter test pilot for the Air Force. That all changed when on one day, he was mysteriously transported to a crashed spaceship. There he met Abin Sur, a Green Lantern. Abin Sur was dying and offered Hal the opportunity to succeed him. Hal Jordan accepted.
With the ring in his possession, Hal Jordan became the greatest member of the Green Lantern Corps. He became a founding member of the Justice League and has helped save the world countless times.
That changed when Hal couldn’t save his hometown, Coast City, and it was destroyed by the villains Mongul and a Cyborg Superman, killing millions. This event shattered Hal and sent him on a dizzying course of destruction.
Hal tried to use the power of his ring to bring back Coast City and its citizens. But the Guardians of Oa, the leaders of the Green Lanterns, forbade him to do it. This sent Hal on a mission to get the full power of the ring from the Central Battery on the planet Oa. Hal seemingly went mad, when a parasite creature entered his body and Hal stopped calling himself Green Lantern, and emerged as Parallax.
His mission to restore Coast City destroyed most of the Green Lanterns and Guardians of Oa. Parallax was set to redo history as he saw it with the full power of the Green Lantern Central Battery, but the heroes of the DC universe stopped him. Alongside those heroes was the last of the Green Lanterns, newly appointed Kyle Rayner, who was given the power ring by Ganthet the last of the Guardians.
In the end, Hal, as Parallax, sacrificed himself when a giant alien was devouring the sun. Hal used his powers to reignite the sun and in doing so sacrificed his life as well. His spirit went and became one with the Spectre. An avenging spirit of God who righted wrongs and persecuted the guilty. Hal’s penance had begun.
But this was not Hal’s end. It was discovered that Parallax was an ancient enemy of the Green Lanterns and was imprisoned in the Central Battery for eons. This entity was still with Hal, but with the joined effort of the remaining Green Lanterns, (by this time there was John Stewart, an alien named Kilowog, current GL Kyle Rayner and onetime Lantern Guy Gardner, they reinstated Hal’s spirit into his body and defeated Parallax, sealing him again into the Central Battery, and restoring the Guardians to oversee the Green Lanterns. Hal is now the core Green Lantern of the DC universe.
