The region of the Eye constitutes its own reality, existing within both the material universe and the warp. Although planets and star systems exist within the Eye, the laws of reality no longer apply. Time is a meaningless concept, and matter, thought and energy are indistinct.
The worlds within the Eye are known as Daemon Worlds and each constitutes its own bizarre sub-reality.
The warp and real-space are indistinct and intermixed within the Eye, and the whole region is a maelstrom of psychic energy, impossible to navigate through. Imperial ships avoid the area around Eye for thousands of light years. Ships travelling too close to the Eye can be thrown far off-course - they can also be caught in temporal whirlpools which carry them backwards or forwards in time, or which trap them in limbo forever.
The warp storms that disturb the Eye are so intense that there is little point in even trying to steer a ship in a particular direction. The Chaos renegades simply launch their ships into the swirling energies of the warp, trusting fortune to carry them to their enemies. This makes Chaos attacks so random, sudden and unpredictable, often occurring on worlds far from the Eye.1
The Eye as a Refuge
The Eye offers a sanctuary to the worst forms of traitors and heretics forced to flee from Imperial justice.
For the Traitor Legions the Eye of Terror has been their exile, sanctuary and safe haven for ten thousand years, from which they strike out at opportune, seemingly random, moments. The Eye is also sanctuary for the most heretical renegades, fugitives of Imperial justice and traitors throughout the galaxy, and all are welcomed as fellow enemies of the Emperor and the Imperium.
Mortals within the Eye are constantly exposed to the effects of Chaos, physically warped so their bodies come to reflect their flawed natures; the Death Guard, for example, worship Nurgle, Chaos God of Decay, so that their bodies become bloated and putrid.
The shock of the birth was so great it could not wholly be contained within the warp, but spilled out into reality through the minds of the Eldar. Consequently the Eye covers most of the region of the former Eldar Empire. Other zones of overlap were created, but the Eye is the most significant.1
The Imperial world of Cadia lies nearest to the best-known stable gateway into the Eye; consequently it is the most fortified and militarized world in the Imperium, the first line of defence against Chaos incursions into real space. It would seem that ships exit through this gateway far more often than they enter it.
Abaddon the Despoiler led an attack through the Eye of Terror during a massive narrative campaign that decided the fate of Cadia and many other systems.2,3
Sectors and subsectors surrounding the Eye of Terror2,3
- Belis Corona - (sector) heart of the Imperium's naval efforts and its docks are listed in von Heffman's Glorium Imperialis as one of the wonders of the Imperium. It is said that the entirety of Battlefleet Obscurus could dock in the vast orbital shipyards in orbit above Belis Corona.
- Medusa - (subsector) famous as the homeworld of the Iron Hands chapter. Unlike many other parts of the Eye, life is hard and uncivilised barbarians cover many of the planets.
- Scarus - (subsector) the most populous of all the sectors, with no less than six Hive Worlds which come together in trade and commerce and mutual defence. There are also numerous temperate and agri worlds to support the Hives. There are also two Forge Worlds which supply the vast Scarus Defence Forces, Nysa Stromolo and Mordax Prime. It is said that 7/10 of Thracian Primaris, the capital of the sector, is covered in Hive cities.
- Scelus (sector)
- Sentinel (sector)
- Belial IV (subsector)
- Cadian - (sector) the Cadian system is possibly the most well known system, with its 1st Imperial Guard Regiment having many successful campaigns and gaining wide recognition. Abaddon the Despoiler had attempted a campaign against the system; after he was repelled by Imperial forces Cadia was made a fortress world against the sporadic attacks of forces in the Eye of Terror.
- Chinchare (subsector)
- Nemesis (subsector)
- Caliban (subsector)
- Agripinaa (sector)