Sharuum

Sharuum is a female sphinx and the Hegemon of Esper, Alara.

Centuries old, Sharuum has long since commanded the inhabitants of Esper. Her lover, Crucius, introduced etherium to the plane. Although unable to create the alloy herself, Sharuum taught the mages of Esper to thin existing etherium via the creation of etherium alloys. After Crucius disappeared, Sharuum devoted much of her life to finding the whereabouts of her former partner.

During the Conflux, many of the leaders of Esper were slain during Malfegor's march against the shards. Hopelessly outnumbered by beings that were once her allies, she fled and secluded herself to prepare more stringent defenses.

Test of Metal
Due to problems presented within the text itself, and details later revealed, the canon of Test of Metal is dubious.

Some time afterward, Sharuum encountered the planeswalker Tezzeret. He convinced her that Crucius was still alive, and he would be willing to show her what had become of him. She made a deal with Tezzeret that she would trade him all of her possessions, her power, and her throne for even a small amount of time with Crucius. She revealed a number of riddles to Tezzeret to aid him in his quest. These led him to Kemuel, Sharuum's son.

Later, Sharuum traveled to the Metal Island, an island comprised entirely of etherium, but her own etherium was stripped from her body. Tezzeret quickly treated Sharuum's wounds and reunited her with Crucius. Keeping to her word, Sharuum promised Tezzeret all she had. Tezzeret's only command for Sharuum was to return to Esper and rule as she always had.