Edited by Jyothi.

It is a well-accepted fact that Sequencers do not have a shared physical form. Though all remaining Sequence members have since long relinquished whatever physical envelope they once possessed to embrace a shape best described as a "sapient cloud of baroque ornaments", they did not appear this way in the first place. All evidence points to the idea that the Sequence is not attached to a specific species but can instead be understood as a symbiosis of a vast number of different civilisations and physical shapes having merged under the same organisation and aesthetics. In fact, considering the age of the Sequence (about ten to twenty million years) it is entirely possible whatever species or conglomerate of species once founded the Sequence doesn't exist anymore.

Many long-lasting interstellar civilisations are based on this "meta-civilisation" model but the method through which the Sequence united its components is, as far as we know, unique. And, to be honest, terrifying. Much more than what we originally expected. And for the record, our initial hypothesis was galactic wars of extermination.

1 - Sequential History

At the core of the Sequence is a concept born somewhere on one of their original homeworlds ten million years ago: when considered at a specific moment in time, civilisations have no existence in and of themselves. They're just people, buildings, armies, but they're not ideas. What makes a civilisation is its history. To vanquish a civilisation, to conquer it fully, one has to conquer its history.

When the Sequence targeted a specific civilisation it had deemed worthy or interesting, it started by studying its history in full, often reaching a higher level of understanding and knowledge than the locals. Then it would start interfering with this history. The first level of interference took place over the course of decades and consisted in slowly seeding doubts about the validity and reality of this civilisation's historical records. This doubt-creating phase would in time enable the Sequence to sever a civilisation's link to its own past by burying it in false truths, conspiracy theories and misrepresentations. These endeavours would grow in scope and scale to the point the Sequence would find itself in nigh-complete control of the target civilisation's media and data infrastructure, signalling the beginning of the second phase. Over a few centuries, the Sequence would rewrite their target's history in order to insert themselves within it, with the end goal of making this civilisation believe it was always part of the interstellar empire. A wide array of methods were used for this purpose, from the widespread falsification of historical records to collective consciousness manipulation. In the end, the target civilisation would join the Sequence peacefully without even noticing the transition, convinced of having always been a small element of the sprawling empire. The method was incredibly effective. It is estimated that between one to two hundred thousand civilisations were absorbed in that way over the course of ten to twenty million years, most of the time with minimal bloodshed. Even vast interstellar empires, initially similar in power to the Sequence, fell to this method called the Sequence of History.

It is to be noted that the Sequence used a variant of this strategy against rebelling factions or civilisations, erasing their history without replacing it with anything, leaving billions of sapient creatures in a timeless fog, devoid of identity or temporal depth.

What about civilisations that did not have a concept of history? It seems the Sequence did not even consider them as such, seeing them as feral animals that could only be eliminated. Interestingly enough, three known civilisations managed to resist the Sequence of History. The Forgotten Travellers, which could communicate faster than the Sequence (due to being an AFAL civilisation), noticed and responded to initial interference attempts in a timely manner. The Vriij, which could manipulate the memories of other sapient beings and reshape their personal or collective histories, proved impervious to the second stage of the method. And a mysterious civilisation the Sequence only named as "Cyclicals", that seemingly had a non-linear perception of time and as such proved to be completely impervious to their attempts, going as far as casually rewriting their own history to counter Sequence interference.

2 - The Remembrance War

As time passed, several prominent figures or factions (if there is a meaningful difference) within the Sequence started to lament the sheer loss of knowledge that came with the expansion of the empire. An order of historians and librarians rose from the ranks of those who had been tasked with carrying out the Sequence of History, with a new mission: to harness and preserve the collective timeline and deeds of the countless societies erased and merged within the Sequence. To each erased civilisation now corresponded mystical archives, set aside from the wider Sequence and curated by xeno-historians. Most of the archives were not much more than discreet buildings in Sequence megalopolises. However, some interstellar empires were vast and complex enough for their archives to take the shape of hollowed-out planets filled with vaults, tombs and vast networks of library-cathedrals. These planets were isolated histories frozen in time: the Sequence called them the Fragments, one of the empire's most well-guarded secrets.

And then, some two million years before present, an incident only known as the Reveal led to a widespread backlash against the Fragments, which were declared anathema. In Sequence parlance, this meant they were now eligible targets for interstellar wars of extermination. As they were part of the Sequence, the Fragments should not have been destroyed by strength of arms. Their populations were to be granted the honour of collective suicide, followed by the self-destruction of the planets.

Instead, the Fragments fought back. The librarians were also soldiers, wielding the power of many a Myriad, the Sequence equivalent of legions and navies. For millions of years, they had collected the knowledge of lost civilisations and, in many ways, had grown more attached to them than to the Sequence itself. When relativistic shells and black hole weapons started raging above the Fragment worlds, a powerful cult revealed itself within the librarians: the Lodge. It did not just seek to protect the Fragments. It wanted to recreate the dead civilisations, making them rise from the dead and walk the galaxy again. And to achieve this purpose, the Sequence had to die.

The resulting three-way galactic war was cataclysmic.

The loss of lives probably numbered in tens of trillions and millions of planets, but the Sequence had already gone through exceedingly destructive wars, with the Vriij conflict, in particular, ravaging entire regions of the Okean cluster over less than two millennia. The real devastation of this war wasn't in material terms.

Faced with defeat and the threat of ritualistic genocide, the Lodge started giving the Sequence a taste of its own medicine. Hiding behind the unwilling shields of the Fragments' defenses and military, the rogue librarians leveraged their vast knowledge to compromise the very history of the Sequence. Their weapons were Nulls: advanced AI/transbiological systems that scoured the databanks and networks of the empire, modifying historical records, erasing specific parts, rewriting events to the point of simply destroying the collective history of the empire. The empire replied with its own historical institutions and Nulls but their efforts were built on top of an already crumbling structure. After fifty thousand years the empire had ceased to be a coherent civilisation united by a shared past.

The first part of the Sequence of History had been applied to its very creators.

There was no second part. The Lodge did not fill the void it had created. The war fizzled out, its original casus belli having vanished in the limbo that was now imperial history.

The Lodge had effectively killed the Sequence with its own weapons.

Illustration from the Wootha Public Domain Release.