In the 70's there was a cartoon show called The Freedom Force that had five different heroes and unfortunately only five episodes. The members of that group were Isis, Hercules, Sinbad, Super Samurai, and Merlin. I remember the series well but I only just found out about the predecessor to that show, called Space Sentinels which actually lasted for a full season. In this series, there were only three heroes, each of a different race, Hercules (the well known White guy), Mercury (an Asian super speedster), and Astrea.
Astrea had the power to turn into nearly any living creature which, in this series, meant she could morph into any animal. Apparently she could fly too which makes her that much better than Jayna of the Wonder Twins. Apparently all three of the main characters could fly and had been granted eternal youth as well. I've had a chance to check out a few of the episodes and it seems that Astrea was the most level-headed of the group and with her ability to get into and out of tight places, she usually got to the bottom of things first. Mercury was a bit of a Joker and Hercules always seemed to encounter things that were stronger than him.
This series was noteworthy for its multicultural cast. It's also great to see a Black super heroine with a major role in an animated series, especially in the 70's. Regardless of how great she was, she didn't make the cut when the doomed series changed to become the even more doomed series, The Freedom Force. Still, Astrea is a part of history and apparently available on video. Both series are contained in one DVD set available here. How did this Black woman become Astrea? The brief origin of the trio is explained in the opening narration of the series.