Goratrix

Goratrix, charmingly named "The Betrayer" was the most ambitious, talented and reckless of Tremere's seven disciples. He was the mage responsible for creating the potion that turned the Tremere into vampires, and responsible for convincing the rest of the House to adopt it, neglecting to mention certain undesirable side effects.

Goratrix' ambition eventually led him to defect to the Sabbat in the 18th century, forming a parallel society, the House Goratrix, conventionally called the Tremere antitribu. The House continued to exist until 1999, when Tremere, losing his war with Saulot, possessed Goratrix and sealed his soul in a mirror. Tremere then destroyed the antitribu, leading to the end of Goratrix' short-lived but infamous unlife.