It was said that Golgoth could be summoned from the Round Loaf by an individual who read from the grimoire. One winter, on the winter solstice, Morgan Hurst captured Tom Ward in order to use him as a sacrifice in the ceremony. After digging through the snow on that winter's day, they descended underground stairs and arrived in the chamber where Golgoth could be summoned.
As Tom watch, Morgan did summon Golgoth, but the creature's power was sapped and destroyed because he had been summoned within a magical barrier, meaning he could not escape. This was because the Spook had made a fake copy of the grimoire for just these circumstances. (The Spook's Secret)