When and where the Eldar first began using Wraithbone is unknown, though most Imperial scholars assume it was in the distant past, long before humanity had even fully evolved to sentience. It is used to create the Craftworlds of the Eldar, all of their edifices, their tanks and other vehicles, robotic constructs such as the Wraithguard and Wraithlords, as well as their individual weapons and armour. It is a psychic conductor and thus provides not only the structure and armour for the things built of it, but also the power distribution and communications systems since Wraithbone carries psychic energy the way a wire or fiber optic cable carries electricity or photons. Wraithbone can also naturally generate a psychic shield that protects the occupants of any spacecraft made from the material