Nubia

Nubia was Wonder Woman's "black sister", created from black clay, just as Diana was created from white clay. Both were brought to life by Aphrodite, but Nubia was stolen by Ares/Mars (the Greek and Roman names were interchangeable, and more often than not, the Roman names were used. Mars was one of the gods whose Roman name was used.), so Nubia did not get the powers that was given to Diana.  Mars raised Nubia to be his warrior, giving her a special ring to keep her mind clouded. Years later, Diana met Nubia, who became her roommate. After several battles, Wonder Woman was able to release Nubia from Mars' control, when she used the heat of the sun, reflected off her bracelets, to cause the ring to expand and fall off. Nubia defied Mars, and optioned to lead her warriors to the ways of peace. It was then that Queen Hippolyte revealed the truth: Nubia was Diana's sister! (1)