"This world is hidden from the sight of the Warp in the same way that its surface is concealed by pollution. A fog of some sort conceals it, and surely some other dark secrets."
- —Codicier Miguel Gricalo
As it attempted to recover from this crisis, the other worlds of the region began to enter their own crises. Without any external assistance, the survivors were unable to even fully restore the world's core functions.
Over time, the world's Human population reverted to a primitive culture that dwelt upon the planet's terribly polluted surface. More recently, horrific creatures have begun to emerge from the planet's core to wreak havoc among the descendants of those survivors.
The xenos presence continues to increase in severity. Unless some external forces join the conflict, the xenos could soon exterminate the limited remaining Human presence.
In the Golden Age of the Jericho Sector, Sagacity was a well-supported and productive Hive World. The devotion of its population to the God-Emperor was unquestioned. Sagacity had raised at least six regiments of Astra Militarum forces in addition to its native Planetary Defence Force.
The three major hive cities imported vast quantities of foodstuffs to preserve a population of more than thirty billion souls, but Sagacity also produced huge quantities of refined goods for export and her natural supplies of valuable minerals also contributed to feeding the world's ravenous manufactoria.
For generations, the world was considered a model of the Imperial ideal. Loyal, productive, and rapidly growing, many assumed that Sagacity might someday become the jewel of the Jericho Sector.
The inhabitants of many other worlds began to view Sagacity with a terrible envy. This was particularly true among the sector's Agri-Worlds and many of its own colonies. The fruits of their labours went to Sagacity, but few of its manufactured products were sent off to these less sophisticated markets.
Many viewed the Hive World as an opulent paradise where many luxuries were taken for granted and few suffered from lives of menial labour. While this was hardly the case, it was certainly the perception.
In the early days of the 37th Millennium, Sagacity was struck by cataclysm. A rogue planetoid impacted with the planet. The resultant devastation vaporised much of her oceans and turned the skies black with debris for centuries.
Quakes rippled across the planet as its very tectonic plates were shattered by the force of the impact. All three of its hive cities collapsed when the structures were subjected to unprecedented geological shifts. Billions of Human lives were lost as the very substance of the world was torn asunder.
The Agri-worlds and colonies that might have been able to assist Sagacity's recovery refused to send assistance. Their leaders saw the collapse as Sagacity's due comeuppance for centuries of arrogant dominance.
A few of the sector's other Hive Worlds prepared to send mercy missions, but only a few arrived and none were able to make a significant impact upon the massive crisis.
Reconstruction would have taken centuries to complete, but as other worlds were subsumed by the sector's Age of Shadow, this proved an insurmountable task.
Without any external support, the vast majority of those who survived the initial cataclysm were unable to persevere on the remains of their shattered world.
More than another sixty percent died off in the few Terran years that followed. All were exposed to the world's toxic atmosphere and many prayed for the God-Emperor's mercy as they endured endless nights beneath a canopy of dense clouds.
Food and potable water soon became the most precious commodities. Most of the world's stores and treatment facilities had been destroyed.
Only a limited supply of new foodstuffs was provided to the survivors from off-world. Millennia of function as a Hive World had devastated and polluted much of the planet's surface and biosphere, so that it could no longer be used for agriculture.
As more and more of the population died, dark legends also began to circulate among the region's void travellers. Some said that the deaths were not just from living in the waste. Rather, these legends recounted hideous xenos that had emerged from the planet's depths, awakened by the cataclysm.
Other stories suggested that the world's inhabitants had been cursed for their sin of pride. These myths also promised that any who interfered with their penance would suffer the same fate. The combination of these tales kept off-worlders from travelling to Sagacity and also prevented anyone from attempting to aid the refugees in escaping the devastated world.
None, however, knew the darkest of secrets. Millions of years in the past, Sagacity had been a significant Necron world. During the War in Heaven, one faction actually launched the rogue planetoid towards the world.
Though they knew it would take millions of standard years to arrive, these ancient beings had foreseen that Sagacity could one day become a thriving centre for the Necrons. When the planetoid struck, it was intended to shatter the planet and destroy the Tomb World, preventing it from ever recovering.
The attack failed. Though many of the world's stasis crypts were shattered, several reacted to the cataclysm by activating emergency defensive measures. For more than four thousand Terran years, the world's Necron forces have been in the process of gradually activating and awakening.
The sundering of Sagacity's crust was not as devastating for the Necron forces as it was for Humanity, but it did inflict a significant amount of damage. Many of the world's stasis crypts were obliterated in the impact. Others collapsed as tectonic plates shifted in an unprecedented fashion.
Huge amounts of cosmic radiation that slashed through the damaged atmosphere destroyed the ancient recordings on a few others, which held the memory engrams of some of the sleeping Necrons. The Necron forces realised that most of these disasters could be overcome, and they also accepted the fact that reconstruction would take an extremely long time.
For millennia, Necron scarab constructs struggled to repair the subterranean structures, using whatever equipment could be salvaged from damaged structures.
At the same time, forces of Canoptek Wraiths explored the surface and began the tedious process of cleansing the world of any contamination -- primarily, the Human survivors. Due to the limited resources available, this process was agonisingly slow, even for a species as patient as the Necrons.
Recently, Sagacity's Necron forces have become much more aggressive. When the forces on Nunc began to awaken, a signal was broadcast to a select few of the Jericho Reach's other worlds. The signal was meant to activate a number of Tomb Worlds, so that their forces could prepare for a new Necron offensive.
More and more of the surviving stasis crypts have activated since that message was received. Tens of thousands of Necrons have been activated and have joined in the reconstruction and cleansing efforts. The world's Null Field Matrix has even been activated, to protect it against any contamination from the Warp.
Ancient records indicate that Sagacity was once a bountiful and lush paradise. Her forests and seas were vast and teemed with life. The soil was rich and well suited to Humanity's preferred agricultural crops. The temperature range and atmosphere were ideal over much of the world's surface, so that Humans could enjoy the beauty of the planet's natural environment.
The completion of the first hive city began to reduce the world's natural splendour. As additional hives were completed, the planet's population increased as did its level of environmental pollution. Over the centuries, the world's atmosphere, soil, and waters all turned from benign to toxic. Much of the planet's native flora and fauna underwent severe mutations and a great deal of it died off.
However, that environmental damage was trivial compared to the devastation wrought by the planetary collision. In an instant, the seas boiled, the atmosphere exploded, and the plates that underplayed the continents were shattered.
Even though this event took place Terran millennia ago, Sagacity's atmosphere has yet to fully recover from the sudden influx of pollutants. Most of the wildlife that had survived the pollutants introduced by the hive cities were unable to cope with the sudden new changes.
During the centuries of darkness, almost the entire native flora of the world died out. Without plants to replenish the world's oxygen and aid in the filtration of its pollutants, the atmosphere soon became even more toxic.
Over the millennia, little has changed. Sagacity's natural environs remain inhospitable to any Humans that attempt to venture across it without some protection. Most of the surviving Human mutants rely upon filtration systems or rebreathers -- some of which have been passed down through generations for millennia.
At ground level, visibility rarely extends beyond twenty metres. Fungal scrub life and toxic swamp waters filled with aggressive, mutated animals represent the majority of Sagacity's living threats.
Few actual plants remain on the planet. Instead, a broad variety of different fungal life forms have emerged to fill that ecological niche. Some of these are even capable of sustaining the atmosphere, producing oxygen through a variety of biochemical reactions that draw their energy from sources other than sunlight.
These include organisms that rely upon heat and unusual chemical sources. However, none of these processes are anywhere near as efficient as those of photosynthetic plants. As a consequence, the restoration has proceeded extremely slowly.
The Necron presence has done little to aid this process. Their approach to most of the world's life has been a systematic pattern of slash and burn. The biological consequences of a toxic atmosphere hold little meaning to these undying, cybernetic xenos.
However, they realise that the long term ramifications are extremely damaging to all of the planet's biological population. The Necrons of Sagacity hold all such life forms in disdain. They consider the destruction to be a worthwhile pursuit and have committed significant resources to its completion.
As these xenos have continued their own reconstruction, the darkened skies have been a boon to their efforts. The thick cloud cover is impenetrable by visible life and resistant to most types of scans. Consequently, the Necrons have been free of the intrusions of most prying eyes.
This has enabled them to devote all of their resources to the reconstruction of their shattered tombs without having to commit a significant portion of their forces towards defensive measures.
With this in mind, they have often chosen to take measures that keep the atmospheric pollution in place until such time as they are prepared to commit their forces in their battles against the galaxy's other life forms.
Since Sagacity's cataclysm, the world's Human population has survived in the most primitive and barbaric state. Few remain, and those survivors are all horribly mutated. They survive only by tenacity and violence. Many of the small tribes devoted themselves to the Ruinous Powers in the hopes of finding divine intervention.
Others have become so primitive that the very notion of worship is beyond their mental capacity. At the same time that they attempt to contend with the harsh ecosystem, the mutant populace has been culled by Necron forces. This has resulted in a population that is focused upon hiding from the xenos whenever possible and fighting desperately when necessary.
The Humans largely exist as small isolated tribes. Some of these groups dwell within caves near the planet's surface. Others have reverted to an arboreal lifestyle. Very few dwell in exposed structures upon Sagacity's surface. Of those few that attempt it, all maintain a nomadic existence.
Because of this constant movement and separation, any descriptions of a universal culture would be misinformed. Each tribe has its own collective personality. A few barely have any language capacity, while others retain a spoken language that is closely related to Low Gothic.
Of course, any attempt at communication with these miserable wretches ignores the mutations that have become commonplace. By any reasonable Imperial standard, these creatures are only nominally Human. More realistic classifications would identify them as mutants that are only suitable for destruction.
Imperial forces might visit Sagacity to combat the Necron threat, but it would not be to assist these Humans. Rather, their extermination would be nearly as high a priority as the destruction of the xenos contamination.
Of note, the Necrons have not been as aggressive as might otherwise be expected of that mechanical species. Their efforts to destroy the remaining Human populace seem unfocused. This is likely because the majority of their resources have gone towards recovering from the cataclysm.
Though it has taken millennia, it is likely that this task has been resolved to whatever extent it is possible. Certainly, the Necron presence on Sagacity is less than it might have been had the planetoid never struck the surface, but these xenos do still maintain a major presence. If the intent of the ancients that launched the attack was to annihilate the Necron encroachment, the attempt must be considered a failure.
Most recently, all signs indicate that the Tomb World has re-established contact with the other Necron forces on Nunc. The presence on Sagacity is clearly much more limited than the one on that world, but it has also begun the process of reawakening all of its forces.
Countless xenos structures have emerged from deep beneath the planet's surface, forming dozens of tomb cities. A significant number of the various subtypes of these xenos have begun to make their presence felt. At least two Dolmen Gates are also active upon the world's surface, and forces have been sent off-world.
Neither the native Humans nor the forces of the Imperium are yet aware of this fact. Only the Necrons themselves know where these units have been sent.
Over the course of the past year, continuously more complex Necron forms have begun to emerge from the stasis crypts. This may be an indication that the majority of the Necron Warriors and Canoptek Scarabs have already been activated. The complete nature of the world's holdings remains unclear.
An increasing number of more sophisticated specimens, including a variety of xenos vehicles and specialist organisms, have begun to emerge. It seems likely that, unless this is part of some more complex strategy, the Necrons should soon move to secure their holdings. Such an initiative is likely to prove terminal to the surviving Human tribes.
- Deathwatch: The Outer Reach (RPG), pp. 89-91