|Location/Habitat||Various worlds throughout the universe|
|Abilities||Different with each psyker|
|Threat Level||Varies, although generally Dangerous or higher.|
The Imperium of Man uses a system to rate a psker's power. The system uses Greek letters. Once the system reaches sigma, it turns from psychic potential to psychic blanks, who possess the Pariah Gene. The most powerful grades are:
- Alpha Plus - The most powerful psykers, Alpha Pluses are described as being able to "turn a man inside-out with a glance", "snap a Battle Titan in half with a flick of the wrist", and "a muttered syllable can turn an army upon itself in a frenzy of blood lust." They possess the ability to destroy a planet, sometimes unintentionally. The Emperor of Mankind would be considered an Alpha Plus, although his own abilities far surpass those of an average Alpha Plus-rank psyker. It is possible that the Alpha Plus level is merely anti-mutant propaganda created by the Imperium, as psykers are viewed in the same light as Ogryns and Ratlings.
- Alpha - The next most powerful type of psykers, Alphas are close to the estimated power of an Alpha Plus. An example would be the psyker Esarhaddon, who was powerful enough to control hundreds of Imperial citizens and guardsmen at once, but not powerful enough to destro even a Scout Titan, let alone a Battle Titan.
- Beta - Betas are noticably weaker than Alphas, although are still quite powerful themselves. An example was Sergeant Agun Soric, who, without proper training, could detect blood poisoning in his fellow guardsmen and send himself messages from the future by writing them on bolter rounds. Once he had recieved training, he gained the ability to ressurect the dead members of the Tanith regiments in the form of "Warp Ghosts", which acted and behaved as they did during life.
- Sigma and Lower - Sigmas and lower are psychic blanks. They suffer from the Pariah Gene, which makes them practically invisible to the Warp. The most notable members include the Imperium's Culexus Assassins and the Necron Pariahs.
Known Psyker ClassesEdit
- Astropaths - Short for Astro-Telepath, Astropaths are used by the Imperium to send messages across the galaxy.
- Navigators - Navigators are used by the Imperium to navigate through the Warp. Their third eye can send a man insane within seconds and kill him in minutes.
- Sanctioned Psykers - Sanctioned Psykers serve the Imperial Guard in specialist units. Most of them end up dying at the end of a Commissar's bolt pistol, earning them the nickname "Bolt Magnets". Those who survive a term with the guard and the tests of will and mental fortitude they go through upon returning to the Adeptus Astro Telepathica are trained as Psykers Primaris.
- Librarians - Librarians are members of the Space Marine chapters who possess psychic potential. They are better trained and better equipped than average human psykers, partly because of the process of turning a man into a Space Marine.
- Grey Knights - The Grey Knights are a chapter of Space Marines composed entirely of high-powered psykers. They are used by the Inquisition's Ordo Malleus (Daemon Hunters) to combat the daemons of the Warp.
- Inquisitors - Though it isn't a requirement, most Inquisitors are psykers themselves. The powers of Inquisitors vary, but can be anything from a blast of psychic energy to influencing or even controlling a weak-willed enemy.
- Warlocks - Warlocks are the most common kind of psyker found among the Eldar. They usually serve as the leaders of Guardian squads.
- Spiritseers - Highly trained warlocks that serve instead to lead either the Wraithguard or Wraithblades, or as a Farseer's bodyguard.
- Farseers - Farseers are the most common leader of an Eldar warhost. Unlike the other leaders (the Autarchs), they are powerful psykers, more-so than Warlocks, and will usually use their powers to shape the battle in the Eldar's favour.
- Sorcerers - Sorcerers are the psykers of the Chaos forces. They range from the Heretic Sorcerer of traitor guard forces (pictured above) to the powerful Sorcerer Lords, such as the Chaos Lord Ahriman, who sometime lead Chaos Space Marines into battle.
- Weirdboyz - The Weirdboyz are the only active psykers in the Ork race, themselves already powerful latent psykers (the difference being that normal Orks can't call upon psychic abilities, in combat or otherwise). They use the collective power of the Orks, known as the Waaagh!, to annihilate their foes. However, too much power results in what is known as the 'Eadbang, where the Weirdboy in question's head will explode, generally killing anyone nearby, Ork or not.
- Tyranids - All Tyranids possess the potential to be powerful psykers, through the Hive Mind's constant mutation of the miriad species of Tyranid in it's fleet. However, most Hives restrict the use of psychic abilities to synapse creatures (those that can command the forces of the hive), such as Hive Tyrants, Norn-Queens and Warriors, or to the psychic weapons platforms known as Zoanthropes.
Psykers possess a myriad of abilities, grouped into numerous disciplines. Each psychic discipline opens up numerous abilities to the user, based around a common theme that is defined by the title given to said discipline. For example, pyromancy refers to the use of psychically generated flames, whilst biomancy refers to the use of psychic abilities to change one's physical form. The main disciplines are:
- Biomancy - The manipulation of biological energy and processes with the power of one's mind. Biomancers are masters of the flesh, learning to shape and influence the physical forms of themselves, their allies or their enemies, according to their will.
- Divination - The ability to look into the Immaterium and discover possible future events, sometimes even influencing these events towards a more favourable outcome.
- Pyromancy - The ability to create searing infernos out of thin air. Pyromancy is one of the most spectacular and destructive forms of psychic ability, and those who face a pyromancer in combat are often reduced to nothing more than a pile of charred bones.
- Telepathy - The ability to contact or even control the minds of others. With a single thought, a telepath can blast away his foe's sanity, induce states of numbing terror or even possess his victim's thoughts and control their actions, the victim becoming little more than a living puppet of the psyker's will.
- Telekinesis - The ability to manipulate the material world with the power of one's minds. Telekines can lash their foes with psychic energy, erect invisible force shields to protect themselves and even rend apart the fabric of reality itself.
In addition, most alien races, as well as numerous Space Marine chapters and the followers of the Chaos gods Nurgle, Tzeentch and Slaanesh, have developed unique disciplines to aid themselves and their comrades on the battlefield.