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"A Grey Knight's greatest weapon against the Warp is not his blade or bolter but his mind and the will to bend reality and rend his foes with but a thought."

— Brother Librarian Clavanus

A Grey Knights Librarian

A Grey Knights Librarian is a psychic specialist within the Grey Knights Space Marine Chapter. These exceptional individuals are powerful psykers who have proven to possess a strength of mind far greater than that of their fellow Battle-Brothers, and are able to wield their psychic abilities freely.

These formidable Librarians possess a will of iron, for they must, as the powerful sorceries they wield are far more potent than those of their equally psychic Battle-Brothers. Grey Knights Librarians have sharpened their psychic powers to a razor-edged weapon against the daemonic.


All Grey Knights possess a degree of psychic ability which is further developed and enhanced by their years of training on Titan. While only a handful of Battle-Brothers ever achieve the levels of power commanded by the Chapter's Librarians, they are all capable of manifesting certain powers and abilities, especially in the company of other Grey Knights where they can combine their gifts to create great effects and more devastating psychic attacks.

Grey Knights do not suffer the corruption of the Warp and are nigh invulnerable to its longer-term effects. While daemonic forces may effect them physically, or even confuse them, they are the purest of Space Marines and the most resistant to the powers of the Empyrean. Grey Knights are far less susceptible to insanity than normal men and their constant exposure to daemonic horrors and foul Warp sorcery hardens them against the worst of its effects.

To be a Grey Knight is to constantly face madness, death, and far, far worse. To fuel their supernatural abilities, Grey Knights draw on the limitless potential of the Immaterium. However, the Warp is anathema to humanity, filled with predatory creatures and malign intelligences. Should a Grey Knight drink too deeply from the Warp’s power, he runs the risk of attracting the unpleasant attention of its denizens.

A psyker as well-trained and pure as a Grey Knight learns how to mask his presence from the creatures native to the Warp. He can moderate, or fetter, his powers, reducing the amount of Warp energy he channels through his mind. Doing so has the drawback of reducing the sheer power of his abilities, but his presence does not stand out amongst the Warp's chaotic, shifting tides of energy.

Of course, sometimes caution must be forsaken if the circumstances are dire enough. Just as the Grey Knight can temper the power he taps from the Warp, so can he exceed his limits and gather as much as his psyche can hold, and more. This is known as "pushing," and both the results and the consequences can be truly impressive.

A Grey Knights Librarian unleashing his power

Grey Knights train to fight as small units in battle. Each member of a squad supports the others with close combat attacks and well-placed Bolter fire. This unity of purpose and high level of training extends to their use of psychic powers, and Grey Knights have developed the ability to manifest their abilities by tapping into the psychic potential of the Battle-Brothers around them. Grey Knights may only combine their psychic powers with other Grey Knights; they cannot include any other kind of psyker who is not trained in their specific methods, including other Space Marine Librarians.

On the battlefield, Grey Knight Librarians use their powers to support their Battle-Brothers. This often manifests in a display of raw psychic might, such as a cataclysmic Warp rift or bolt of eldritch lightning. Yet it is perhaps the Librarians' subtler powers that have the most effect.

With a little effort, a Librarian can summon others to his side, cloak them in protective shadow, or imbue them with great strength. Little is beyond a Librarian, for in the Sanctum Sanctorum is recorded every conceivable psychic ability, sigil of power and sorcerous incantation, and it is from here that the Librarian chooses his weapons for the battles to come. Thus is a Librarian amongst the Chapter's most versatile warriors.

Yet for all the contributions a Librarian can make to a Grey Knights strike force, his most vital tasks are carried out within the walls of the fortress-monastery on their Chapter homeworld of Titan. It is here that the Librarian will school new recruits in the mysteries that all Grey Knights must know: the six chants of denial, the seven words of life and death, the eight songs of battle, the nine terrible spells that form the basis of all magick and much more besides.

A Librarian's tutelage is a most rigorous process, and many Aspirants do not survive, for it is better for a weak recruit to perish at a Librarian's hands than for him to imperil the Chapter through his inadequacies. Yet if the Librarians are called upon to be ruthless, there is little cruelty in their actions, and no malice. This culling of the weak is merely a necessity -- for the Grey Knights to remain incorruptible, they must be as hard of mind and will as they are of body.

A few Librarians are fortunate enough to reach an age when their bodies can no longer meet the rigours of campaign. Such warriors are removed from the Chapter's fighting roster entirely, and retire to the labyrinthine corridors of the Sanctum Sanctorum of the fortress-monastery on Titan to take up guardianship of its musty crypts. Only these ancient ones know the full catalogue, for there are some secrets buried therein of which even the Grand Masters are ignorant. Such mysteries can never be allowed to escape the confines of the Sanctum Sanctorum, for the fear is ever that even some amongst the Grey Knights would not prove immune to their temptations.


At the height of the tallest tower of the Grey Knights' fortress-monastery, high enough that its spire pierces the toxic skies of Titan, sits the aerie, known as the Augurium, of the Grey Knights known as Prognosticars. Few souls, even amongst the Grey Knights, ever set foot in the fortress-monastery's Augurium. Sixteen thousand steps lead from the base of the tower to its pinnacle, which can also be reached by a slow lift ride, or in cases of emergency, a teleportation platform.

Once a Grey Knight arrives at the top of the tower he emerges into a preparation chamber, the marble floor patterned in pink veins, with two Paladins arrayed in Terminator Armour standing watch before a great gate of blackened bronze. The marble with pink veins in the stone is said to come from Terra itself, for this kind of marble does not form naturally anywhere else in the Sol System.

The bronze gateway opens in stages, rattling and clanking, accompanied by the withdrawal of sliding bars that keep the portal sealed shut. When it finally rumbles open at last, both doors grind back on heavy tracks, close to three metres wide. Within this sacred candle-lit chamber lies the inner sanctum sanctorum of the Prognosticators.

Within its mirrored walls, the Grey Knights' Prognosticars go about their rituals and meditations to the light of guttering candles. Prognosticars are powerful, highly specialised psykers, who are particularly sensitive to fluctuations in the Warp and who read psychic tremors in the Immaterium to predict the location and severity of forthcoming daemonic incursions.

Only those Knight-Brothers that show the most promise with their powerful, latent psychic abilities are chosen for this onerous duty. To be pulled from service within a squad and isolated from the rest of the Knighthood is said to be an honour, of course. Such a position carries rank and responsibility, but it also comes with its share of sacrifice. No one wishes to stand alone on the fringes of an order founded on the collective strength provided by brotherhood.

Whilst the skills of the Prognosticars might seem oracular in form, in function they are much more akin to highly specialised hunting instincts, tracking the unholy spoor of Daemons through the roiling tides of the Immaterium. It is a Prognosticar's duty to hunt through the Sea of Souls, seeking the ripples caused by the Archenemy's greatest intrusions.

Forewarned by the Prognosticars, the Grey Knights can deploy their forces according to the nature of the threat at hand, rather than relying on delayed or misleading reports from a battle zone. Though such predictions are prone to a certain amount of inaccuracy, the Prognosticars provide the Chapter with a level of foresight without which its mission would be all but impossible.

If a Grey Knight commander orders the destruction of a passenger liner to ensure the banishment of a single daemon hidden aboard, he does not do so out of callousness, but out of pragmatism. Thanks to the warnings of the Prognosticars he knows that the escape of that daemon would lead to the damnation of far more souls than those that perished in the liner's destruction. In the Grey Knights' war against the daemons, the tally of the slain can only ever increase -- all the Sons of Titan can do is moderate the collateral damage. If millions must be sacrificed to save billions, then so be it.


  • Aegis Armour
  • Aegis Terminator Armour
  • Psychic Hood - Like all Librarians, a Grey Knights Librarian's Psychic Hood is an arcane construct of psychically-attuned crystals that allow him to amplify his abilities whilst at the same time disrupting the manipulations of the Warp by another psyker, making it easier to nullify their psychic powers.
  • Wrist-Mounted Psycannon
  • Wrist-Mounted Storm Bolter (Optional replacement for Psycannon)
  • Nemesis Force Sword
  • Frag Grenades
  • Krak Grenades
  • Psyk-Out Grenades
  • Liber Daemonica - The Liber Daemonica is an enduring symbol of the Grey Knight's devotion to his mission, and contains the cardinal tenets of lore culled from the dark knowledge caged within the Sanctum Sanctorum's walls. Every Grey Knight carries a copy of the Liber Daemonica in a Ceramite case on his breastplate. These gnarled tomes contain the Chapter's rites of battle and detail the traditional duties of every Grey Knights' rank. The books themselves are also potent psychic talismans in their own right, with pages illuminated in silver and bound to a spine carved from the thigh bone of a martyred Imperial saint.

Grey Knights Librarian Psychic Powers

The Grey Knights’ selection of psychic powers has been formed over a millennia of combat against the worst monsters the galaxy has to offer. Whilst these powers are most commonly used by Grey Knight Librarians, it is not unheard of for an Ordo Malleus Inquisitor to learn these abilities or an Imperial Guard Primaris Psyker to train in one of these rare Disciplines. The psychic powers of the Daemonhunter are not subtle — they are weapons of war against the most terrible foes of the Emperor of Mankind. They include:

  • The Canticle of Absolution - This ancient rite is used by the Grey Knights to banish daemons and purify locations where they have laired; it is also known as the Six-Hundred-and-Sixty-Six Secret Words.
  • Dark Excommunication - The Grey Knight weaves an enchantment that severs a daemon's connection to its dark master, one of the Chaos Gods, causing it to dissolve into the Empyrean.
  • Hammerhand - Focusing the raging power of their minds, Grey Knights can augment their already prodigious might. Even unarmed, such a warrior can crush flesh and bone -- given blade or warhammer there is little limit to what they can slay.
  • Holocaust - Units of Grey Knights Terminators are able to make use of the Holocaust psychic power as a whole. A group of Grey Knights can harness their collective psychic powers to manifest this ability as long as the entire group remains focused on its manifestation. If successful, a Grey Knight Terminator can incinerate opponents at close range using this power. It is a manifestation of the hate the Grey Knights feel for the daemonic, and is completely capable of burning a daemon's physical body to ash. This power is especially terrifying because whatever is destroyed by the Holocaust power dies in the Warp as well, its spirit extinguished like a candle. It can burn the souls of mortals to nothing and can banish daemons as if they were but a bad dream. This power is a lesser version of the extraordinary final burst of psychic power used by the Emperor of Mankind Himself to snuff out the soul of Horus in the Warp at the end of the Horus Heresy during the final battle on Horus' Battle Barge, the Vengeful Spirit.
  • Might of Titan - Summoning up the power of the Chapter’s ancestors and calling on the sacred genetic heritage of the Emperor Himself which all Battle-Brothers possess, the Grey Knight Librarian is able to harden muscles and boost the strength of those allies in close proximity to him.
  • Mind Blades - The Grey Knight imbues the blades and other melee weapons of his allies with unerring accuracy and the ability to seek out even the smallest of chinks in their foes’ armour, helping his friends land devastating blows to quickly despatch their enemies.
  • Nemesis Hammerhand - When summoning this ability, a Grey Knight Librarian is able to put the strength of his mind behind the blows of his fists or weapons, striking fiercely enough to wound even the toughest foes. This ability is particulalrly potent against daemons and other creatures infused with Warp energy.
  • Quicksilver - Quickened by the Librarian's uncanny mind, his fellow Grey Knights' reflexes are increased to an uncanny speed and swiftness.
  • Sanctuary - Chanting words of binding, the Librarian creates a shield of psychic turbulence to hinder his foes. This barrier extends out around the Librarian in a 10-metre-radius and impedes all those who attempt to cross. The barrier does not impede a Grey Knight's movement in any way.
  • The Shrouding - Through prayer and the combined gestalt psychic power of the Grey Knights, they are able to blind their enemies to their location through their sheer faith in the Emperor and the power from the Warp this faith can draw. This protects them from ranged attacks and enhances their stealth. The Shrouding extends out around the Grey Knight in a 20-metre-radius and makes those within it hazy and indistinct when viewed from without whilst not restricting the vision of those within it.
  • Smite - Lethal bolts of Warp lightning leap from the Librarian's fingertips, tearing his enemies apart in a barrage of psychic energy.
  • The Summoning - The Librarian is able to reach out through the Immaterium and call upon his allies, drawing them across the intervening distance in the blink of an eye. The Grey Knight can use this power on a number of allies, though he must have met each one personally and must know them by name so that he can recognise their presence in the Warp across space and time. When he invokes this power he "calls" to these chosen allies and they are instantly aware that he is summoning them. If they choose to answer the call they are instantly transported through the Warp to his side.
  • Vortex of Doom - The Librarian is able to open a tear between the material realm and the howling destruction of the Warp, unleashing devastating energies that utterly consume his foes.
  • Warp Quake - The Grey Knight Librarian causes the Warp to tremor, causing denizens of the Empyrean to lose their hold on realspace and any device or technology that uses its power for guidance to fail.
  • Warp Rift - With a simple gesture, the Librarian is able to rend the material realm asunder, creating a miniature Warp rift and condemning his foes to the caprice of the Immaterium.


  • Codex: Grey Knights (5th Edition), pp. 9, 24
  • Dark Heresy: Daemon Hunter, pp. 117-121
  • The Emperor's Gift (Novel) by Aaron Dembski-Bowden