had been replaced temporarily by child actors after Master Vile had used the Orb of Doom to revert time by approximately ten years. Billy acted in this period as a liaison between the Aquitian Rangers and Earth. It was the cure for Billy's reverse-aging that eventually served as the plot device by which he was removed from the show. When Power Rangers Zeo began, Billy officially retired from active Ranger service as the six-man team now only had the five segments of the Zeo Crystal as a power source for each member of the team, allowing Tanya to take his place while he continued his supporting role by creating and maintaining most of the weaponry, gadgets and Zords the Zeo Rangers would use. Power Rangers Zeo The writers left the choice open as to whether or not Billy would become a Zeo Ranger, with him musing at the start of Zeo that he could always assume the Zeo power in an emergency. He graduated earlier than the rest of the team in "Graduation Blues," and then left Earth for a brief period to address problems on the planet Aquitar. In "Mr. Billy's Wild Ride," he returns to Earth, although he is attacked by the machine empire along the way. Before the Gold Ranger's identity was revealed as Trey of Triforia, the writers left several red herrings to mislead the viewers into believing that the Gold Ranger was Billy since he was never around when the Gold Ranger was around. When Trey of Triforia returned to Triforia on sabbatical to try to unify his three selves, Billy was selected to assume the Gold Ranger's powers. However, the negative proton energy that his body had absorbed in the Command Center's explosion prevented him from taking the powers. Instead Jason Lee Scott, the former Red Ranger, received the powers. By the time of Jason's return it's shown that Billy has worked his way up to a black belt in karate. Billy was last seen in two of the final Zeo episodes suffering from accelerated aging, a side effect from the regenerator he used to restore his proper age. To counter this, he traveled to Aquitar for a cure from their Eternal Falls (analogous to the Fountain of Youth), which would restore his real age; after that he opted to remain there with Cestria, a female Aquitian with whom he had fallen in love.