Wraithknight - Role: The psychic link between the rare pairs of Asuryani identical twins is like no other. Whilst alive, these gifted individuals can sense the proximity, the mood, and even the thoughts of their counterparts with the ease that a normal Asuryani could feel the sun on his skin or the wind in his hair.The bond is so strong that should one of the twins die before the other, the surviving brother or sister will often fade away in sympathy.Sometimes, when such a soul-reaving loss has taken place, the surviving twin will sacrifice what is left of their life to pilot a Wraithknight for their craftworld.The essence of the dead twin is transferred from the Infinity Circuit of their craftworld into the large Spirit Stone in the chest of the giant Ghost Warrior, whilst the surviving sibling enters a near-permanent battle trance within the fitted cavity behind its breastplate.The clarity of thought provided by the living twin ensures that the construct moves with the speed typical of the Aeldari species, whilst the psychic link between the pilot and their departed sibling allows them to commune with not only the animating forces of his twin, but also the spirits of former incumbents that once controlled the construct's long-limbed form.The great measure of control afforded by this gestalt mind gives the pilot mastery over the construct's psychically-powered weapon systems and affords the war machine an acrobatic grace that belies its massive size.It is well that each Wraithknight is capable of such feats of heroism, for it is they who are at the forefront of the quest for new Asuryani Spirit Stones.By passing through forbidden portals and traversing the shattered multidimensional spars of the Webway, Wraithknights can emerge onto the surface of Crone Worlds, where the nature of realspace shears with that of the Warp.It is the metaphysical friction of this unnatural union between the energies of the Immaterium and realspace that causes reality itself to bleed, each drop of unleashed psychic energy from the Warp crystallising into a new Waystone ripe to house another Asuryani soul and so become a Spirit Stone.Only a Wraithknight can endure the Warp-touched environments and daemonic infestations that plague these lost planets and return with their bounty intact.Those mortals who embark upon such perilous missions risk not only their life but also their eternal soul. Only the Wraithknights have the power and resilience necessary to harvest a clutch of Spirit Stones and still escape from the nightmarish denizens of the Crone Worlds.As the end of days approaches and instances of birth become ever more eclipsed by reports of death, fewer and fewer pairs of Aeldari twins are born upon each craftworld.A great many Wraithknight pilots are recruited from Revenant Scout Titan helmsmen who have lost their own Aeldari twins in battle and, driven to regain their kinship whatever the cost, give themselves over to the twilight life of a Wraithknight pilot.As unsettling as it may be, it is whispered that some craftworld councils are removing the option of choice from such individuals. Desperate times call for desperate measures, after all -- should a pair of twins be too attached to the light of the living world, it is possible to steer them toward a darker fate.