In the early 1970s, Michael Eisner, who joined ABC in 1966, became the network's program development manager. He helped bring about ideas for many series including Happy Days (which originated as a segment on the anthology series Love, American Style), as well as several soap operas; however, Eisner's main credit at ABC was for developing youth-oriented programming. He was responsible for reacquiring the rights to the Looney Tunes-Merrie Melodies library, bringing the shorts back to ABC after spending several years on CBS, as well as developing The Jackson 5ive animated series and a series about the Osmonds, and greenlighting Super Friends, based on DC Comics' Justice League of America series. Eisner left ABC in 1976 to become president of Paramount Pictures (and would later become the President of ABC's eventual parent company, Disney).
What supergroup did Eisner develop a cartoon around?