The Skull of Yoruk was a magical artifact. Formerly an internal organ of the hero Yoruk, it was imbued after his death with the soul of Deep Magic. In 883 GUE, it was stolen by a pack of Grues, who took it to the historic White House. The Brogmoid Brog reclaimed the skull and returned it to AFGNCAAP in 1066 GUE via time tunnel. The wizard Belboz remarked that, despite hundreds of years of use and decay, the skull had remained "quite shiny."
The Skull, as seen in Belboz's Magicatronic message