Witch-skull

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Witch-skulls were apparently-human skulls left over after the death of a Fendahl Core. Each notably had a pentagram burned into its forehead.

The Collection of Necessary Secrets included a collection of witch-skulls found in Peking. Each one had a perfect pentagram burned into its forehead, which Vatican investigators concluded had been done while the owners were still alive, presumably as part of a pagan rite. In 1799, Cardinal Catilin showed the witch-skulls to Marielle Duquesne. (PROSE: Christmas on a Rational Planet)

Dr Fendelman found one witch-skull in the remnants of a volcano in Kenya. He discovered that it was twelve million years old, far older than humans had existed; x-rays revealed a pentagram-shaped pattern in the crown of the skull. When this skull, Eustace, was activated, it began pulsing with a golden glow, and it caused severe mental pain upon physical touch. (TV: Image of the Fendahl)