Xyra was the daughter of a once powerful but ousted pharoah. Upon seeing her father's palace be overun with wild and angry citizens, she led her father down to the underbelly of the palace and killed him.
Xyra has magic powers, and she used the Jewel of Eternity to prolong her life in the 21st century. The Jewel of Eternity is a magical transmitter that syphons lifeforce from anyone in the vicinty who holds jewel or sacred stone.
Xyra was defeated by Danger Girl when Silicon Valerie dropped and hence smashed the Jewel, therefore killing her ability to stay alive.