Mind Flayers are very much in the backstory of the present campaign I am running, so I have been delving into what I can learn about the ancient Illithid Empire. The most succinct informative notes I could find are originally from Nar
here and the
Wikipedia Illithid article. I merely re-edited the details for my post.
The Illithiad suggests illithids may be from the Far Realm, an incomprehensible plane completely alien to the known multiverse. There is no mention of time travel in this theory. Instead, they emerged somewhere countless thousands of years ago, beyond the histories of many mortal races, and spread from one world to another, and another, and so on. It is explicitly stated in this book that the illithids appear in some of the most ancient histories of the most ancient races, even those that have no mention of other races.
The supplement
Lords of Madness provides that the Illithid were a star-faring people who existed at the end of time. Facing annihilation, the Illithid traveled to the past, arriving roughly 2000 years before the present. In these two differing versions of the story, much of the variance hinges upon a fictional text called
The Sargonne Prophecies. The Illithiad described the Prophecies as misnamed, and that much of it sounds more like ancient myth than prophecy. Lords of Madness takes the name more literally, and states that The Sargonne Prophecies are in fact prophecy—or, perhaps more accurately, a history of the future.
According to the Lords of Madness history, Illithids are one of the few races respected by the aboleths. This is because the aboleths remember the origin of almost every other race, through their hereditary memory. However, illithids, as far the aboleths can remember, just appeared without preamble, which scares them.
Another version comes from
The Astromundi Cluster that the illithids are descended from the outcasts of an ancient human society that ruled the now-shattered world called Astromundi. The outcast humans eventually mutated, deep underground, into the mind flayers. In the retconned history of the illithids found in either The Illithiad or Lords of Madness, the emergence of illithids in Astromundi becomes a freak occurrence due to the intervention of Ilsensine through its proxy, since the illithids of Astromundi have their own histories as emerging solely upon that world.
However and whenever it occurred, when the illithids arrived in the Material Plane of the far past, they immediately began to build an empire by enslaving many sentient creatures. They were very successful, and soon their worlds-spanning empire became the largest one the multiverse had ever seen. They had the power—in terms of psychic potency and the manpower of countless slaves—to fashion artificial worlds. One such world was this empire's capital, called Penumbra, a diskworld built around a star, which was a thousand years in the making. Such was their might that the Blood War paused as the demons and devils considered a truce to deal with the illithid empire.
Eventually, the primary slave race of the illithids developed resistance to the mental powers of their masters, and revolted. Led by the warrior Gith, the rebellion spread to all the illithids' worlds, and the empire collapsed. The illithid race itself seemed doomed.
The Ancient Illithid Empire
The book and adventure series, The Illithiad and
the Overmind adventure arc by Bruce R. Cordell, first introduced the ancient Illithid empire in-depth into the ancient empire's capabilities. Unlike most assumptions of the ancient illithid empire, illithids are fully capable of faster-than-light space travel and may possibly be the only D&D race capable of doing so.
Truespace
Completely different sets of natural laws govern the crystal sphere containing Penumbra, the ancient capital of the Illithid empire, from normal wildspace. “Truespace” is weightless and airless; however, objects cast adrift from worlds and planetary bodies do not possess a residual gravitational field, nor are they fortunate enough to gain an envelope of breathable air.
Player characters who gaze through the ventral observation ports see a star-sprinkled void not unlike the landscape visible during their trip through wildspace. However, the uncounted stars visible in Truespace all lie within the same crystal sphere.
This is basically all saying that the Illithid capital is the one known place in the D&D multiverse containing realistic space. The size that Truespace needs to be to have a full night sky is questionable but its probably at least a few hundreds of not thousands of light years at minimum.
Ancient Nautiloid
The nautiloid uncovered in Masters of Eternal Night is not the same class of nautiloid used by present-day illithids. The nautiloid is completely sealed, and it can maintain an internal atmosphere even when physical environments and natural lawa fluctuate and vary between worlds. The construction of the nautiloid is in some ways akin to terrestrial ships; however, every surface is molded and smoothed, alternating between mirror-bright surfaces and resin-like projections.
Here is a sentence from the adventure that indicates these nautiloid ships are metal:
Voor larvae consist of whatever material their spores used to form their chrysalises. In the cast of the nautiloid-composed voor, the creatures consist of a metal- and mucous-mixed resin.
The ancient vessel discovered by the PCs is self-powered and partially autonomous; PCs who place the brainmate in this cradle activate the ship. A ghostly voice, or perhaps a mental whisper, speaks:
"Reinvgoration protocols executed and successfully completed. Navigation coordinates successfully installed. Destination: Penumbra. Awaiting launch command, or alternate coordinates. Artificial attraction field initiated. Air generators online. Heating filaments energized. Lockdown on exists successful. Psychoportive propulsion initiated. Remaining travel time to Penumbra estimated at six sleep periods.”
This is where the assumption of faster-than-light comes from. The crystal sphere is probably hundreds or thousands of light years in size at least and the ship can travel through it within 6 days. The map at the beginning shows that you definitely don't enter Truespace directly beside Penumbra either.
Penumbra
When the light of the star becomes more pronounced, PCs can see the structure that surrounds and dwarfs it: an unimaginable large, flat disc with a hole for the sun at its very center. At this distance, PCs see small nubs that must actually be walls thousands of miles high. These walls rise around the hub, ensuring that only glancing rays of the star's illumination actually strike the surface of the disk. PCs dimly see vast bodies of water and cloud cover on and above the disk.
The Illithid Empire crafted a suitable seat for their empire. A thousand years of engineering produced the disc known as Penumbra. The shape of the artificial world mimics a perfectly flat platter, with a star situated in a relatively small hole at its center. To extend this analogy, think of the sun as if it were the size of a pea on a conventional plate. Thus, the radius of the disc itself is a bit larger than the orbit of a conventional world around its sun. The disc is a few thousand miles thick and consists of a nearly indestructible material called substare. The artifact is quite massive and weights far more than the sun itself.
The thickness and sheer size of the disc produces normal gravity on the surface, diminishing somewhat at its edges. The inner wall serves as convenient worldwide shade. creatures on the disc live in perpetual twilight. The inner wall also keeps the breathable atmosphere from drifting into the sun. The outer edges of the disc do not require walls, as the atmosphere flows inward.
This description is basically the standard description of an
Alderson Disk.
At the height of the illithids' empire, mind flayers inhabited both sides of the disc. Thrall races from the hotter worlds lived near the inner hub, while creatures from colder climes lived out near the rim. Though Penumbra consists of unbreachable substare, a hundred feet or more of normal rocks, clay, and topsoil covers this mysterious substance. The illithid builders incorporated artificial magnetic lines through the length and breadth of the substare comprising Penumbra. Thus, a lodestone or compass points the worth north - toward the Shine (sun).
Penumbra did not posses an extensive underdark environment while the illithids held sway above, the mindflayers did delve hollows here and there, fashioning some especially important areas directly into the nigh-indestructible substare that makes up Penumbra. Illithids were perfectly capable of either creating or otherwise harvesting and work with near indestructible scrinth-level materials and at a scale larger than any other races.
Penumbra consists of about 3000 Solar Masses worth of Substare with a habitable space of over 4 billion Earths. The Illithid Empire was well beyond a tech level 15 civilization capable of creating or harvesting 6x10^30 kg of substare a year and producing an average power output of at least 1.5*10^34W over a thousand years.
Voor and the Gith
The closest path to Penumbra lies through a region of space once claimed by the voor. The voor are long dead, but they once provided a terrible threat to the illithid empire. No record of their existence remains, save for a few relics left over from their fight against the illithids.
The nebulae near Penumbra represent the blasted remnants of voor resistance destroyed eons past by the illithids. These vast clouds of dust contain seeds of the voors' vengeance. Like spores or seeds, motes of the interstellar dust settle upon the surface of a nautiloid. Each speck of dust sprouts tendrils that bore microscopic channels in the side of the nautiloid. Thus rooted and planted, a speck "grows," utilizing the material structure of the ship itself to form a complete chrysalis. The brainmate simply reports, "Contact with abiotic organisms detected..."
The voor larvae primarily hate illithids. A voor larva is immune to psionic attacks and any mind-affecting spells, items, or psionic abilities. Voor larvae represent only one form of the creatures that were once collectively known as the voor by ancient illithids.
The people collectively known as the forerunner race represent the root stock from which the githzerai, githyanki, and many other splinter races evolved. The grimlocks on Penumbra were once forerunners manipulated by the mind flayers' psychobiological sciences and transformed into a racially distinct species.
The illithids, then holding mastery of much of the multiverse, encountered the voor against which the mind flayers' psionic powers proved useless. When the illithids' standard thrall troops also proved inadequate to vanquish the voor, the mind flayers began to fear. Out of desperation, a long-vanished Creed began to experiment upon selected thralls using the Tumerogenesis Tanks. Entirely new battle races were developed and imbued with strange abilities. Some races even received psionic abilities akin to the illithids themselves.
If the illithids introduced biogenetic factors for aggression into their thralls, it is possible that this trait survived and carried over into present-day races. Perhaps this genetic tampering is responsible for the long war between the githyanki and githzerai that rages to this day. Though not a commonly accepted belief, some illithids think that it was the mind flayers' triumph over the voor that planted the seeds of the slave revolt,
Note: Any githyanki or githzerai presented with this hypothesis becomes violently agitated and patently refuses to believe that their race relied on anything but their own indomitable will in gaining psionic power and destroying their masters.
With these new powers, the enhanced thralls eventually managed to destroy the voor. With the voor threat neutralized, the illithids euthanized all of the surviving enhanced thralls, or at least they thought so. Some few escaped into the general thrall population.
It is possible these enhanced thralls overthrew the illithid empire. Thus, the illithids may have planted the seeds of their own undoing. This presents a slightly different picture of the Illithid's eventual downfall by the Gith. And it wasn't just carelessness and arrogance but desperation in creating super soldiers against a dire threat that may have led to their downfall.
The Annulus
Beyond a door is a chamber, empty except for a glowing grid of inscribed lines covering a 10-foot-diameter area on the floor. Above this intricate symbol floats a metallic hoop, 1 foot in diameter. The metal of the hoop, or ring, is silvery, and contains many strange and arcane devices and projections. The object is the Annulus.
The Annulus is the ultimate psionic nullifier. Developed over a thousand years of steady effort by an Elder Concord of ancient Penumbra, the Annulus served as the ultimate tool to keep peace among the various illithid Creeds.
At the height of the illithid empire, there were literally thousands of Creeds, all of them with their own vision of how the empire would best be served. In this chaos of differeing viewpoints, however, one Creed in particular was viewed as a dangerous liability. That Creed was called The Friends of Man. Deemed a danger too great to ignore, an illithid Elder Concord convened, and with its blessing, the Annulus was brought to bear on the Friends of Man, wiping them from existence.
In the aftermath of the Friends of Man's destruction, the Elder Concord felt that such power was a thing not be used lightly, and so it was stored for all eternity, practically within reach of an Elder Brain. After centuries, it was almost forgotten, and when the thrall uprising commenced, the Elder Brain guarding the site of the Annulus' internment was taken unawares. If it had been able to bring the Annulus to bear, perhaps the revolt might have gone differently.
The prime power of the Annulus is psionic nullifcation. While grasping the Annulus, the wielder can trigger the psionic nullifcation effect once per year. The wielder must specify a target or group of targets within 500 feet. The target can be as specific as a particular psionic individual or psionic item or as general as a particular grouping of psionic beings that share the same philosophy that are clustered within a 100-foot radius of a center point... the targeted psionic entity (or entities) or psionic device, regardless of any protection it may posses, is nullified with a terrfic explosion. In effect, nothing is left but floating dust.
A more powerful entity (such as a demigod) will tax the Annulus to its limits. If the Annulus is used to nullify such a target, the Annulus success, but it is also completely destroyed, and cannot be retrieved by any means.
The Annulus in its original time seems far more long ranged to be able to destroy a creed that was considered such a threat to the Illithids and even possibly turn the tides of the Gith rebellion.
