Navigator - Warp Eye: Common to all Navigators is the "Warp eye" or "third eye." It almost always manifests as a literal mutation they bear upon their foreheads, although in some cases trepanning and a cybernetic shutter implant made during adolescence will be needed to affect the full release of their power.This third eye is what gives a Navigator their power to gaze into the Warp and guide starships through its turbulent currents and storms -- more than a mere additional sensory appendage, the third eye is the source of a Navigator's power and their link to the Immaterium.A Navigator's third eye often resembles a normal Human eye at birth, but as the Navigator grows in power and age and the eye is exposed to the horrors of the Empyrean, it changes. Gradually the eye's sclera and iris darken and the organ hardens until it becomes a solid, black sphere.In some extreme cases the eyelids may also shrink or disappear entirely, leaving a single black orb upon the forehead. The eye retains its connection to the Warp even when extracted from the body and while it will not kill anyone gazing into it, it can still erode their sanity and send them into a psychotic frenzy or otherwise erode their mental stability.Through their third eye Navigators can see directly into the Warp, and when their power is honed, pierce material barriers and disguises, and even delve into the souls of mortals. They can also use this third eye to read the currents of the Warp -- its ebb and flow -- and through this understanding subtly alter it, causing ripples that can be felt within the Materium of realspace itself.In addition to these lesser powers, the gaze of a Navigator's Warp eye when fully opened can kill, its baleful light sheering the very souls from those that look upon it, extinguishing them forever in a moment of blazing madness and agony.The Warp eye is also the Navigators' most obvious mutation but often not their only one. It marks them out as a mutant and divergent from the greater masses of Humanity, and whilst their position, wealth and bearing serve to protect them from persecution (at least most of the time), Navigators are still feared and distrusted by many others for their gifts, and not without cause.For this reason, Navigators tend to cloister themselves away from other people, seek the protection of bodyguards, and use hoods and cowls to hide their Warp eye when in public.The Navigators' Warp eye has other powers too, although these are employed far more rarely and are the subject of some mystique. These powers develop with the Navigator's experience of the Warp, so that they are most often developed by the potent Navigators known as the "Heirs Apparent."It is said that the third eye of a Navigator has prophetic powers and that it can literally see into the future. Navigators are very reluctant to talk about their powers, and it may well be that only the Paternova, the political leader of the Navis Nobilite, understands the full potential of a Navigator's psychic abilities.Not least of the Warp eye's powers is its singular ability to deal death; any normal person meeting the Warp eye's gaze can be killed in an agonising fashion by sudden mental exposure to the Warp. Due to this danger, Navigators generally keep their third eye covered with a bandanna or similar barrier except when they are taking a starship through the Warp, causing many people to doubt that the third eye even exists.Of course, the unique abilities of the Navigators have their limits. Outside the range of the guiding light of the Astronomican projected by the Emperor's presence in the Warp and powered by the thousands of psykers sacrificed to Him every solar day, the Navigators are far more limited in their ability to guide a starship through the Warp.During the Macharian Crusade beyond the bounds of the Astronomican, that grand Imperial conquest of the outer reaches of the galaxy almost ground to a halt as the sight of the Navigators failed, for they could sense only darkness around them.There are places in the galaxy that Navigators avoid at almost any cost. Navigators will shun the Eye of Terror and thousands of light years of space around it rather than risk a minor deviation in course which might take them close to or across its boundaries.Most Navigators have personal experience of close encounters with Chaos near the Eye of Terror, and many more can recall the names of others who travelled too close to the Eye in a foolish attempt to cut solar days from their journey time only to vanish forever.