Geth

Geth is a Moriok lich-head who was instrumental in the fall of Memnarch. He is now one of the Seven Steel Thanes of New Phyrexia.

The Fifth Dawn
Geth ruled the Mephidross from the throne in the Vault of Whispers, owing his power to having control over the only Vampire in the Dross. This would eventually, however, lead to his downfall. One of his many subjects, a man named Yert, ended up allying with Glissa Sunseeker during her trip into the Dross. She slaughtered Yert's Reaper, a very powerful zombie, and then felt sorry when he broke down crying as a result. He agreed to help her achieve her goals so long as she would help him get a new zombie to control. Geth, angered at Glissa's impertinence, ordered his pet vampire to attack, which she defeated after grievously wounding it. With no choice, Geth told Glissa what she wanted to know which got her to leave more quickly. Unfortunately, the vampire's wounds were severe and only an extensive feeding would save it. So Yert was fed to the vampire, ensuring the traitor's death. He did not stay dead, unfortunately, and rising as a vampire himself he overthrew Geth after beheading him. Geth, however, managed to preserve his head as a Lich and agreed to help Glissa acquire the Shield of Kaldra from the new vampire scourge that was sweeping the Dross from his former throne. In exchange for his help though, he wished them to help him acquire a new body. After Karn’s return to Mirrodin, Geth became one of the guardians of the Mirari and was placed upon a Memnite which would serve as his new appendage.

Scars of Mirrodin
It was revealed that, after Glissa Sunseeker disappeared following the events of Fifth Dawn, Geth returned to the Mephidross in his new state, where he struggled to recover control over the nim. During this time, the Phyrexian corrosion of Mirrodin began in earnest, and Geth was offered a new, Phyrexian body - arachnoid, repulsive and unnaturally strong. Using this power, he wiped out contenders to the Vault of Whispers, claiming it back as his own. Now, he rests in Ish Sah, controlling the black lacuna, biding his time and learning about the Phyrexian invaders. He knows that soon, he will have to repay them for his powers, but for now, they - and he too - are content to wait.