Return of Xoriat
Xoriat, the Realm of Madness, home of the Daelkyr, is beyond description. By merely visiting the plane non-natives risk having their minds shattered at the sight of the chaos. 9,000 years ago, Xoriat became coterminous with Eberron, and the continent of Khorvaire was overrun by the daelkyr and their aberrations. This started the Daelkyr War. The daelkyr destroyed the Dhakaani Empire, but were pushed back to Xoriat by the Gatekeepers. Dimensional seals created by the magic of the Gatekeepers, with the help of the dragon Vvaraak, have disturbed Xoriat’s orbit, preventing it from becoming coterminous again. Since then, the Gatekeeper druids patrol the seals to Xoriat, making sure that no abominations return to Eberron. However, not all daelkyr were pushed back, and many of them were trapped in the Khyber
Xoriat consists of many stacks of translucent layers, an apparently infinite amount of planes stacked upon one another. Its inhabitants exist on multiple layers simultaneously. Massive, drifting entities too large to notice visitors to the plane; free-floating rivers of milk-white liquid; rains of blue globes falling from unseen heights, only to burst and release horse-sized ticks when they strike another object — these are typical sights on Xoriat. Gelatinous worms wriggle from layer to layer, wending through tentacled vegetation encrusted with orange moss, all suspended above an amoebic sea.
Time on the plane of Xoriat flows differently from time on Eberron. One minute in the Realm of Madness is equal to one hour on the Material Plane.
Since the end of the Daelkyr War, Xoriat has been kept away from Eberron by the magics of the Gatekeeper druids, taught to them by the ancient dragon Vvaraak. However, the magics of the gates have been weakening over the last thousands of years, and it is presumed that Xoriat will return. Scholars believe that, when the realm of Xoriat was pushed away was when the thirteenth moon of Eberron disappeared. However, this supposition is incorrect.
Even with Xoriat being kept away from Eberron, it is still reachable via portals, summons, planar shifting, and manifest zones. However, traveling from Xoriat to Eberron, or vice versa, is more difficult than with other planes. Since their exile, there have been many who would plumb the secrets of Xoriat and its daelkyr lords, including Cataclysm Mages, the Children of Xoriat6, the Closed Circle, the Cults of the Dragon Below, the dragon Dah’mir, the Gibbering Cult, Ketheptis the One-Eyed Crone, Messal’thirokktan, agent of the Chamber, Mordain the Fleshweaver and the Outguard (a branch of the Karrnathi army)
The daelkyr are the lords of Xoriat. Powerful creatures, the daelkyr can manipulate reality, warp flesh, and are kings of chaos. They were pushed back from Eberron thousands of years ago, but continue to rule Xoriat.There are many creatures who serve the daelkyr, and who may or may not have been created by them, though only some of them are native to Xoriat. The most powerful of them are the illithid.Others include the various species of ethergaunts, who ran Xoriat on behalf of the daelkyr while they were on Eberron.Creatures created by the Daelkyr on Eberron were also pushed back to Xoriat. Those include beholders, chokers, dolgarrs, dolgaunts, dolghasts, dolgrims, dolgrues, fetid fungi, grells, gricks, harpoon spiders, neogis, opabinias, ropers, runehounds, shrieking terrors, tsochars, xenostelids and xorbeasts. Besides the daelkyr, other creatures call Xoriat home, including the adaru, the akleu, the kaorti, the kyra, the odopi, the rukarazyll, the wyste, and the various species of obyriths. Two of the daelkyr’s slave creations, the githyanki and githzerai, fled during the Daelkyr Wars and found homes on other planes. Daelkyr creations that may or may not have been pushed back to Xoriat include those only partially touched by madness, such as daelkyr half-bloods, pseudonatural creatures, and voidmind creatures. Most forms of oozes were originally created by the daelkyr, through their continued creation is at the hands of various arcane masters across Eberron