Micron

Micron is a superhero capable of shrinking and growing his body to any size he wants and can fly. He's the futuristic version of the Atom, an original member of the Justice League.

Biography
After an intense training session, Micron received a distress call from an unknown source about a monorail gone haywire and tried to prevent the monorail from crashing after saving the driver. Micron disengaged the train from its' track and then derailed it. Micron tried to get out of the plummeting train, however Superman (who was under the control of the villain known as Starro) closed the door which caused a force-field to trap Micron inside. The train then trashed into a building which left Micron with horrible injuries.

Micron was placed in a stasis field where he was slowly recovering. Superman tried to finish Micron off, however that was interrupted by the rest of the Justice League who were informed by Terry McGinnis who is the futuristic Batman. Micron was able to get enough strength to get out of the tank and grab Superman with his enlarged hang. However, Superman knocked him unconscious since Micron was still feeble. Micron later was returned to his stasis field where he recovered.

Micron invited Terry to join the Justice League Unlimited after that, however Terry declined his offer and possibly reconsidered the offer after the events of Hush Beyond. Micron appeared in the comics where he and the League helped Terry against the Jokerz and second Matter Master.

Background information
In the Batman Beyond - Season Three (DVD) extras, Micron was intended to be a futuristic counterpart to the Atom. Micron has similarities to bot the Atom and Atom Smasher since he had the powers of both these heroes. Micron's costume resembled an amalgamation of theirs.