The psychoportation network was a passive system and the walls did fracture to the will of the umbralkind. Without a core gate the network hadn't an Id to defend itself with. The main difficulty as it stood was breaking in without being noticed. The tunnels were rarely unoccupied for long or too distant that others would not notice a change in topology. There was a distinct impression of passing two sets of four large swirling grey eyes. None too approving either. The perimeter had several sixteen-many Jinhai organized to carve out and shape extradimensional space for the new psi-forge. They kept the tunnels of the nearby sewers from listing in spacetime while the interior was fabricated to fill the void.
The outer layer was the first built and no void in it but that one stood on dead soil with empty pale trees of carbon structures. Though each looked like one that ought to be quite live with leaves that did breathe they served merely in whole as an apparatus of the interchange. Everything here, as good as a non-euclidean outer layer could define 'here', was an exercise in extra dimensional interfaces. This one designed more aggressive than the last. If one looked up at their tips the sky they joined with those of the opposing floor on the opposing side of the space. There was no sun in the distance but any piercing light from some hundred meters away where a captain looked back at himself in the distance of an insulating monosurface. Only the face was the subtle kind of mirror inversion one's mind would easily notice. Somewhere along that range one would see oneself though not always exact. At his current location he'd the shadows brought with him but shortly away from the quasi-real Way gate they appeared to die entirely within the muted glow.
The 'trees' were branches of a sensory construct that sampled the proxy space surrounding the inner layer. A simple creature easier to writ robust looking for curious abnormalities. None more curious than the captain and his umbralkind. A rustling complain creaked progressively from tilting leaves near him. Haze rising from the soil from the environment. That luminescent fog curls inexorably closer eager to excise a shadowy cancer ignorant of the humankind it was bound to.
At least until someone halted the protective layer's objection to the shadow creature given the offer of the Humankind it lived in. Several small pyramids shot from the ground nearby then raced about the area to take positions. Sybil phased in from the interior with several loud stumps from all directions. Turrets seen creeping forward in the proxy layer as a very tall humanoid figure walked closer. Some pointing toward him from a floor position behind a copse of trees that would otherwise put it out of view if not for the ceiling overlap.
She wore no boots but did wear a heavy blue brigandine apron of some fluidic metal. Auburn hair framing an expressionless burnished face with ratios of beauty arranged to specification by the calculations of an exacting overmind. The sides of her hips at each side of her apron had no evidence of clothing on her faintly bronzed skin though the faint glow marks of hot metal spatters badly losing a war of regeneration on her surface said it little mattered. As she closed the distance trees more small pyramids appeared from foliage and moved entire trees as much as the cooled metal fell away from her too then vanished.
Faint silvery patterns shone on her face as the silvery eyes of the first predator glare, "I do not make peace; I make war against all Aetherkind. What do you want, Humankind? While you are permitted in the fringe the Living Emperor does not take kindly to unknown persons drilling into his forges. Especially not one bound to Umbralkind. If you're looking for the humankind once here we built them a suitable space nearer to the surface."
The shadow might recognize the patterns as true names of strong shadows, demons, undead, and angels alike. The names of their immortal beings now nothing more than a marker. Souls broken and dismantled the hollow names could rise no more.