Magistrate's Daughter

The Magistrate's Daughter is one of the Gibborim, and Earth was never supposed to be her home. Her family was exiled from their own planet aboard a ship piloted by Xavin, a Xartan stowaway, and the exile ended badly: the ship came down on Earth in prehistoric times, her father got clear of the wreck, and she did not. She spent the next eleven thousand years trapped inside it. Like all of her kind she cannot survive Earth's atmosphere in her own form, so life here means taking a human host, and her people's gifts, long life and beams of burning light among them, come along wherever she does.