Cathedral

Cathedral was the center of the Thinking Machine world of Synchrony, where the Computer Evermind Omnius ruled the reborn robotic empire. It was so named because it held the probe that had been launched from Giedi Prime thousands of years earlier, the seed that had brought about the rebirth of the machine empire.

The Giedi Prime probe#

When the machines conquered Giedi Prime before the Butlerian Jihad, one of the first acts of the Omnius entity there was to launch more than five hundred probes into deep space. The attempt at colonization failed on nearly every world the probes reached, but one came down on a far world and began to build a robotic colony city. Long afterward, at the end of the Battle of Corrin, the final Omnius entity made a last attempt to save machine civilization in the face of human conquest by transmitting a radio signal into deep space. The signal carried all the codes and information of the empire, including the minds of Omnius and his savant Erasmus, and as it degraded across the galaxies it was picked up on that same far world, which came to be known as Synchrony.

Heart of Synchrony#

As the machine empire rebuilt itself, Omnius and Erasmus held the original Giedi Prime probe in near-reverence, deliberately raising their new empire around it. The giant flow-metal building that housed the probe, many thousands of stories tall, was given the near-religious name of Cathedral, and the probe itself was enclosed in a four-story, museum-like glass encasement that rotated so that all machines might view it. A high, needle-like copper spire crowned the structure, visible from miles up in the atmosphere when Cathedral was approached from space. Erasmus spent most of his time here, conducting experiments on and directing his Enhanced Face Dancer and augmented human minions, and he pre-programmed into each Enhanced Face Dancer the ability to return to Cathedral as if drawn home.

The Day of Kralizec#

Much of the great day at the end of the age, Kralizec, unfolded in the heart of Synchrony within Cathedral. When the no-ship Ithaca was captured and brought down to the world, the first group of prisoners was taken there. At that time it was believed that the ghola of Paul Atreides created aboard the ship might be the Ultimate Kwisatz Haderach. Because Omnius already possessed a clone of Paul, named Paolo, who might equally have been that being, the machine leader decreed that the two would duel to the death. Paul was brought near death by a mortal stab from Paolo, who in turn fell into an irreversible trance after overdosing on a super-potent form of melange called Ultraspice. As Paul returned from the brink, he declared through prescience that the ultimate Kwisatz Haderach was Duncan Idaho. At the same moment the Oracle of Time appeared in Cathedral and banished Omnius permanently to another universe.

Later that day, Khrone, the machine-appointed leader of the Enhanced Dancers, announced that the Dancers were betraying the machines and would seize the ascendancy of the universe. Erasmus activated the tachyon net and triggered the kill switch set at the base of every Enhanced Face Dancer's skull across the Known Universe. Having merged with and surrendered the codes of Cathedral, Synchrony, and the whole machine empire to Duncan Idaho, Erasmus then died in the chambers of Cathedral.

Afterward#

In the harmonious universe that followed, where machines and humanity coexisted, Cathedral endured. As Synchrony became a training center for the Bene Gesserit and a site of the restored Tleilaxu civilization, Cathedral itself is held to have remained in machine hands.