Necrotecture

Necrotecture is the "art" of building using necromantically animated remains fused with natural materials to create an undead, semi-animate structure. Necrotecture is not constrained by the usual concerns of structural integrity since its animated parts actively work to hold the form together. Neither is it necessarily immobile. Though the colossal Amalgam Ladder is mostly rooted in place, orks use the same construction techniques for their war machines, collection outposts, Grinding Houses, and anything else their fevered imaginations inspire them to build. Placing great value on ingenuity and flexibility, most of these creations - even the outposts - are capable of locomotion.

Utility

The orks of Aestrona developed necrotecture when their efforts to build a tower to the nearest moon reached the feasible limits of the laws of physics. After a brief period of experimentation the entire tower was fortified with undead flesh, which supplied the necessary tension to continue construction. As time passed, the spire began to resemble a gigantic, many-jointed arm rippling with layers of supportive muscles and ligaments and bristling with with animated mouths, claws, and other defensive horrors.
Following their success with the Ladder, the orks began applying necrotecture to every structure and object they built. As a result, orkish structures are horrendously resilient to everything except fire and acid, which can devastate a fortification in minutes. Consequently orks have mastered water oriented magics and have developed highly effective mundane systems of fire control.

Manufacturing

Unsurprisingly, necrotecture is monstrously expensive in both time and materials. Even a relatively small structure could require dozens of dead bodies to supply the necessary parts. Orks keep their material stores stocked with a combination of raiding, animal husbandry, and cloning. Of particular interest are trolls, for their ability to turn food into parts. A single troll is an endless - though time intensive - supply of severed limbs, flayed skin, and living bone. The only reason they are not the ork's favored material is that the quality of their parts is suspect. Far greater quality is found in the Elanni, but procurement can be far more difficult.

Access & Availability

Though technically available to any mystic with a passable knowledge of both necromancy and architecture, the practice of necrotecture was originated by orks and therefore permanently associated with the star-crazed marauders. Even in areas where necromancy enjoys a measure of cautious acceptance necrotecture is actively discouraged, if not outright prohibited. In Graja'did, where the undead are almost as common as the living, necrotecture is reviled above all other taboos. Proven practitioners forfeit all further due process of law and are flayed alive and burnt upon the wreckage of their works.

Complexity

The complexity of any given piece of necrotecture depends on the creator. With a rudimentary knowledge of necromancy and construction an apprentice mystic could create crude structures of vaguely animate flesh, wood, and metal. Greater knowledge yields greater results, but there are few non-orkish masters of the craft in the world, and those hide themselves well.
Orks, on the other hand, possess instinctual mad genius for both necromancy and architecture. Even the simplest orkish structure is a dreadful marvel of ingenuity; multipurpose, mobile, self defending and healing. The greatest work of necrotecture in the world is the Amalgam Ladder, a tower that reaches tens of thousands of feet into the sky and is functionally indestructible.