|Although this article is based on canonical information, the actual name of this subject is conjectural.|
- “Herein lies your truest strength. The energy of the demon. Its spirit. Its heart.”
- ―The Shadowmen[src]
In the Primordium Age, the Shadowmen chose a girl named Sineya to contain the power of the demon. They chained Sineya to the ground then unleashed the demon, which appeared to be in the form of dark vapors. It forcibly merged itself with Sineya, granting her superhuman strength, speed, reflexes, agility, and healing.
Thousands of years later, in 2003, the Shadowmen tried to repeat history with Buffy Summers in order to empower her even more so she would be able to defeat the First Evil's Turok-Han army. However, Buffy sought knowledge, not power, especially if that power meant that she would lose her humanity.
Buffy denied the entry of the demon into her, forcing it and keeping it out. She then broke free from her chains to stop the Shadowmen, thus effectively incapacitating the demon.