This character started out as an android where Professor Ivo put the powers of the superpowered members of the justice league (and that includes the Green Lantern) after he captured them. They managed to defeat the robot and regain its powers. But some time later Professor Ivo rebuilt the robot, but now the android had the power to copy superpowers, and demonstrated the ability to copy equipment. For example, Green Lantern's ring, Batman's utility belt, Wonder Woman's magic lasso.
Powers[]
The Amazo power source replaces the hero power sources. So he's not affected by kryptonite, or a red sun, and doesn't need to recharge the ring.