Hammeroon was recruited by Kyle Rayner to make up his new Corps.  An independent bounty hunter, Hammeroon was in the Liskado system tracking a Kreen wanted for genocide when he came upon Green Lantern Kyle Rayner. The Green Lantern from Earth was about to be devoured by a gittado, a carnivore which used telepathy and shapeshifting to ensnare its prey. A plasma grenade disposed of the gittado and saved Rayner's life.  Unfortunately for the bounty hunter, the gittado had devoured the Kreen fugitive.  Searching for prospective members to form a new Green Lantern Corps, Rayner traveled with Hammeroon to Waystation in the Daffath system. In transit to Waystation, the pair came across the long frozen capsule of Soviet cosmonaut, Anya Savenlovich.  Using the technology onboard Hammeroon's ship to thaw out the Russian female, the group continued on to Waystation.  Once there, they found another member in the form of miner and gambler, Garl Rathbone.  They soon brought themselves to the attention of Waystation's law enforcer, Judge Sool.  After an encounter with Waystation's security androids and chasing the group across the sector himself, Sool would also take up Rayner's cause.  In the new Corps' first mission, Hammeroon gave his life fighting off an invading army led Magaan, another member chosen by Kyle to form the new Corps.  Hammeroon's sacrifice bought his teammates more time to execute their mission.  Afterwards, Kyle disbanded the new Corps, took back the rings, and returned to Earth; feeling he needed more time and experience before creating a new Corps.