"The sundering minor Its legions flush with seemingly endless goblinoid hordes the Imperium had engaged in a long period of expansion; growing to dominate more than a dozen isolates at the height of its power. Virtually every goblinoid of fighting age had enrolled in the legion forming a devastation force that rolled across the cosmos; which left their own isolate vulnerable to an invasion. Unwilling to give up their fertile newly claimed isolates, which had already been divied up, the Senate dithered, bickering over which legion should return. In the end the goblinoid isolate was completely overrun, and connected as it was by carefully engineered shifts to key points in the system the whole Imperium was vulnerable. Goblinoids, in many case freed by their officers (who were themselves goblinoids after years of bloody warfare had taken its toll on the eladrin offier core) broke ranks; streaming back to defend their homelands and families. Concerned about the threat to the entire empire the senate authorized an awesome magical ritual, the like of which had never before been performed in the history of the Imperium, coordinated across dozens of worlds; officially the explanation is that this ritual would "temporarily close all shifts into the goblinoid isolate" giving the Imperium time to muster forces and launch a coordinated counter attack. What actually happened can only be described as a catastrophe. Under the pressure the the goblinoid isolate simply broke; the isolate fracturing and disgorging its contents into all the planes and hundreds of isolates. While small bands of survivors would survive most of the goblinoid population, million of beings, were wiped out in an instant. The Senate attempted to put the best face on things, but an unfortunate word by a shocked arcanist on the Senate floor would give the event it's name... the sundering minor."
Solitudinem faciunt, pacem appellant...
For what it's worth, i'd take your setting any day, Graf...
I'd also like to offer my collaboration specifically to create a pantheon for imperium. I believe the Greek pantheon will be perfect inspiration for this, for various reasons. First, with twelve or so major gods that have both a positive and a negative aspect, it's easy to sum up all the most important spheres of "competence". Furthermore, it is well known how several deities were revered both officially and in "mysteric cults". Adding demi-gods and minor local deities would be extremely easy for that was the nature of the actual ancient greek religion. Finally, acient greek religion had a generational nature, coming from the fact that more ancient gods were actually supplanted by the cults of populations invading the Aegean region, and survived mostly in myths and tradition (the myths have a repetitive nature too: Chronos overthrew Ouranos, and was overthrown by Zeus... who then defeated the primordial and savage forces of old represented by Titans and Hecatoncheires... this works so well with 4e fluff too... the Abys could be well called Thartarus and imprison a "chained god" or two... i'd say it fits)
EDIT: a simple sample pantheon of 12 deities, very basic. Obviously the names are not very appropriate as they are too reminiscent of the actual greek names.
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Deiòs: The god of kings. He governs the sky, the thunder and lightning. The eagle is his symbol, as it is one of the symbols of the Imperium. He is said to have defeated the Primordials and brought peace to the Cosmos.
He also has a somewhat tyrannical and capricious aspect too, and storms are often explained as a manifestation of his anger.
Hadeys: The keeper of the dead. His name is not spoken least it brings misfortune to those who utter it. He is said to dwell and rule in the Shadowlands.
Poseeydus: Ruler of the Seas and great Lakes, he has influence over the winds, sea travels, and waterbound beasts. He's a feared deity and always sacrificed to before long travels (note: in absence of great seas or oceans, this may be a deity governing the shift passages?)
Phoebus: God of the Sun and light. He is said to give mortals the gift of prophecy and foreseeing. In his angered aspect, he is the god of archery and pestilence.
Proserphones: Bride of Hades. Goddes of melancholy and gloom, but also tied to the seasonal cycle and land fertility.
Eefeystos: God of Fire and forge. Mostly revered by dwarves, he is often depicted as maimed. A secluded god, dwelling in the Elemental chaos.
Aressus: God of war and strenght. Mostly tied to the violent aspect of battle, he is often given the attribute of cowardice. Often revered by goblinoids.
Hermethis: God of trickery,lies, travel, and luck. He's considered nimble and witty, and often revered by thieves and rogues. He is also said to show the souls the way to the afterlife.
Palladys: Goddess of wisdom and intelligence, but also tied to wars and protection. One of the most revered deities in the Imperium.
Arthamis: Goddess of woods, virginity, hunt and wild beasts, sister of Phoebus. She often represents the wildest aspect of the natural world. Highly revered by feys and other wood-dwelling creatures.
Erath: Bride of Deiòs, goddes of queens and priestesses. She watches upon the order, both in the family and the State. Keeper of traditions, she's also referred to as the goddes of righteous revenge.
Aphrodeys: Goddes of love and passion. Representation of beauty and charm. Also in his hostile aspect, the deity of blinding passion and disorder, and illusions.
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