Alisa of the Silver Hair

As a child, the eponymous heroine is betrayed by three jealous friends who throw her into a pit and leave her to die.
But Arisa perserveres: she trains herself to be smarter, faster, and more beautiful than any of them before returning for revenge.
Years of living underground have left her hair silver, so her victims can't be sure whether the resemblance is real or a product of their guilty consciences…