Sool was a Green-Lantern, inducted when Kyle Rayner briefly revived the Corps. Originally a judge on WayStation, Sool presided over a case involving Rayner, Hammeroon, and Garl Rathbone after a gambling-related brawl. A believer in law and order, Sool was prepared to sentence the defendants to RoundAway, when Anya Savenlovich interrupted with what appeared to be a bomb (which was, in actuality, part of Hammeroon's ship). The distraction provided the trio an opportunity to escape.
Not one to let a defendant get away that easily, Sool pursued them to a samaritan house on the third moon of B'llth Nine. While he and his guards attacked, a space-time anomaly washed over the planet, destroying everything in its path; it was only because of Rayner's timely intervention that Sool wasn't killed. Back in the samaritan house (contained in a bubble constructed by Rayner), Sool attempted to place them all under arrest, and was attacked by Hammeroon. Rayner offered them all a place in a new Green Lantern Corps, and they all accepted.
The Van'n ImperiumEdit
Investigating the anomaly, the newly minted Green Lanterns came under attack from soldiers of the Van'n Imperium. Recognizing them, Rayner explained the situation to the rookie Lanterns, who were shocked to find out that the Imperium was led by fellow inductee, Magaan. The Corps attacked the Imperium, with Rayner assault the fleet, while Sool and the others attacked Magaan's fortress. Once inside, the group encountered Phothus, a disembodied brain created by Magaan to aid in his conquest. Hammeroon, with whom Sool had shared an antagonistic relationship, went to deal with a swarm of lobotomized soldiers, while Sool, Anya, and Garl worked to remove an inhibitor device that kept Phothus from controlling the antimatter weapon.
The group succeeded, but unintentionally set off a doomsday device in the process. As the planet was destroyed, the Lanterns worked together to create a sphere to protect the fortress from the device. Rayner disbanded the Corps, and Sool and his fellow former Lanterns went into business for themselves. Calling themselves The Corps, and joined by newcomers Bekk H'wat, Way, and Sinara, they continued fighting crime, albeit without rings.