Some time later, during a period where Gardner was performing his duties as a backup Green Lantern, Hal Jordan's power battery, the source of the ring's energy, exploded in Gardner's face due to damage done to it by the Crumbler and trapped him in the Phantom Zone. Jordan and Kari Limbo, Gardner's girlfriend at the time, both believed him to be dead, and the two developed a romantic relationship that ultimately culminated in a marriage proposal. Gardner was able to interrupt the wedding by contacting Limbo telepathically. By then, however, Gardner's bus accident, the power battery explosion, his assimilation into the zone, and the subsequent torture at the hands of General Zod and other residents of the Phantom Zone had affected his mind. When Gardner was released from the Phantom Zone, he was diagnosed with brain damage and was comatose for a number of years.