I. The Far Realm Descends
The Venthari had only begun carrying the warnings of the Naerids beyond the Greyspires when those warnings became real.
For centuries after the Upheaval, Eldareth had lived with an unstable planar order. Scholars studied the changed boundaries between worlds, institutions watched for dangerous crossings, and encounters once considered extraordinary became better understood. The Naerids had warned of something less familiar: disturbances spreading through realms beyond Eldareth's maps and dangers severe enough to send an experienced planefaring people fleeing across the multiverse.
There was little anyone could do with such a warning at first. The surviving Naerids had known what they were fleeing, but they had brought no map showing where an attack might come from and no certainty that it would ever reach Eldareth. The Venthari carried what remained of their knowledge to courts, academies, monasteries, and military councils, urging preparations against threats few outside Rimecliff understood.
Then unfamiliar vessels appeared in the skies.
The first were illithid nautiloids, great organic craft unlike the skyships of Eldareth or the crystalline Ithis Veyra. They appeared above settlements and major population centers with little warning. Reports soon followed of towns falling silent, caravans disappearing, and survivors returning with fractured memories of commands they did not remember obeying.
The earliest attacks were scattered enough to be mistaken for isolated planar disturbances. That changed as illithids began striking populated regions in greater numbers. Their psionic abilities allowed them to disrupt defenders before conventional battle had begun. Soldiers turned upon companions, commanders issued orders they did not remember giving, and civilians were forced into obedience without understanding what had happened to them.
Other aberrations followed as breaches widened. Beholders attacked fortified positions, Grell hunted above roads and damaged settlements, and Neogi moved through conquered territory taking captives for slavery and trade. Tsochars were harder to detect, concealing themselves within living hosts and moving through communities already strained by fear and displacement.
Other creatures had no familiar name. Reports described forms unlike known life, unusual movement, and communication that reached directly into the mind. Accounts differed between regions, but the same creatures and vessels began appearing across lands separated by mountains and seas.
The Venthari recognized elements of what the Naerids had described. Records preserved from Ithis Veyra gave scholars a starting point for understanding the invasion and identifying its source in the Far Realm, a region beyond the planar structure familiar to Eldarethian cosmology.
The relationship between the Incursion and the Upheaval remained disputed. The fracture of the Mythal had been followed by widespread planar instability, and some scholars came to believe that its effects had reached much farther than previously understood. One theory held that the disturbance had drawn attention to Eldareth from beings capable of perceiving such events across distant realms.
Whether the invaders followed that disturbance directly, searched for its source over generations, or encountered Eldareth by other means was never established. By the time the Incursion began, however, they had found routes into the Material Plane.
Behind many of the invading forces were intelligences the surviving Naerids had struggled to describe. Eldarethian scholars eventually grouped these entities under the name Great Old Ones. Their relationship with the creatures of the Incursion varied or remained uncertain. Some aberrations appeared to serve them directly, while others acted through instinct, coercion, or purposes that were never understood.
Their influence did not depend upon the Great Old Ones themselves entering Eldareth. It spread through the aberrations crossing into the world, the psychic effects left among conquered populations, and the breaches through which further creatures emerged.
The Venthari quickly became important to the defense. Their inherited psionic abilities and the disciplines developed through the Way of the Celestine gave them experience with mental attacks that most soldiers and spellcasters had never been trained to resist. They helped identify psychic interference, protect vulnerable minds, and teach others how to recognize or resist forms of control used by the invaders.
The Naerid knowledge preserved at Rimecliff also became valuable. Monasteries, military orders, courts, and arcane institutions that had previously regarded the warnings carried by the Venthari as a distant concern now sought whatever records and instruction could be provided.
Even with that knowledge, the first advance moved quickly. Major settlements were particularly vulnerable because dense populations gave illithids large numbers of minds to dominate and provided other invaders with captives or hosts. Some communities came under psychic control before neighboring regions knew they had been attacked, while those that resisted openly faced nautiloids above their defenses and aberrations within their streets.
The invasion did not reach every land at the same time. Some kingdoms received enough warning to reinforce vulnerable settlements and prepare defenses, while others encountered the invaders before they had heard the name Far Realm. Oceans, mountains, and fortified borders offered limited protection against enemies whose routes did not follow the geography of the Material Plane.
Within months, the scattered attacks had become a widespread war. Alliances formed between states and peoples that had previously shared little trust, and resources intended for trade, rivalry, or local defense were redirected toward resisting the Incursion.
As the war continued, the Venthari also turned increasingly toward the Celestine Obelisk kept at Rimecliff. The Naerids had entrusted it to their ancestors centuries earlier, but much of its purpose had remained unknown. Study during the Incursion revealed that the Obelisk belonged to a larger network capable of detecting severe disturbances in planar boundaries and communicating with similar structures elsewhere.
Its greater purpose became clear only when an immense breach began to form and Nyxarath attempted to cross into Eldareth.
The Venthari activated the Celestine Obelisk as the breach widened. Other Obelisks beyond Eldareth answered its signal, and their combined psionic resonance was directed back through the network. The effect disrupted Far Realm energies across the opening, interfered with nearby aberrant forces, and collapsed the breach while Nyxarath was still manifesting through it.
The portion of Nyxarath that had crossed into Eldareth was torn apart as the connection failed. Whether the entity itself was destroyed, wounded, or merely severed from the Material Plane remained unknown.
The collapse of the breach broke the momentum of the Incursion. Aberrations and invading forces already within Eldareth still had to be hunted down or contained, and the damage left by the war did not disappear with the closing of the breach. The Celestine Obelisk had ended the greatest immediate threat, but it did not repair the instability that had existed since the Upheaval.
The Incursion permanently changed how Eldareth understood psionic threats and the regions beyond its familiar planar maps. It also brought the Venthari and the Way of the Celestine into far greater contact with the rest of the world, as knowledge once preserved largely within their monasteries became important to the defense of entire nations.