Editing Psyker (section)

==Psychic Power Hierarchy==
The Imperium of Man uses a 24-point scale (with gradations named for the letters of the Greek alphabet, for some reason; there are 26 points counting the "top" and "bottom", both of which are used to classify entities beyond the scale's ability to measure) called '''The Assignment''' to determine the comparative psychic power of an individual. Unfortunately, this gets very confusing in the [[fluff]], where Alpha-level psykers seem to be a dime a dozen and show up all over the place, and established characters that are canonically high on the scale are completely overshadowed by [[Kaldor Draigo|some other character]]. All of this [[Derp|"logically"]] leads [[neckbeards]] to reach the flawed conclusion that [[Katanas are Underpowered in d20|their favourite character on the tabletop MUST be Alpha level or greater.]] 

Furthermore, it is canon that a psyker's place on the scale can change over time as his or her powers either increase with practice or decrease due to atrophy from lack of use. So generally, the fluff is quite useless for determining who is greater than whom; without the evidence of a direct psychic battle between any two to compare how they match up, it is pretty pointless to use this method.

Lastly, this is an Imperial system, and likely should be used only to assess humans. While chances are someone in-universe has looked at a wyrdboy and gone "Theta-ish", you shouldn't since it's comparable to using metric tools on imperial fasteners: annoying, inappropriate, and probably a crime according to both the Mechanicus and Administratum.  So don't do it.

===Positive Psychic Levels===
#'''Alpha-Plus'''
#*Alpha-Plus psykers '''''do not''''' represent the top of the scale, but are completely beyond the scale. In fact, the scale theoretically continues upwards beyond Alpha-Plus into truly godlike tiers of power, although such individuals have never been encountered, barring maybe the Emperor. Even so, Alpha-Plus individuals operate on a completely different wavelength from normal people and are owners of completely alien mindsets. In terms of power, they are akin to weapons of mass destruction, as in theory there is nothing that a trained Alpha-Plus psyker cannot accomplish through force of will. There is a tacit assumption that this category contains the [[Emperor]] and his "notably-psychic" [[Primarchs]] (especially [[Magnus the Red]] in his daemon Primarch form), but even he admitted there were limits on his power, specifically that one could not be both all-seeing and all-powerful at the same time.  No attempt is made to distinguish power levels among members of this grade, because they're all so absurdly strong there's no point in quantifying it. To put it in context, an emergent Alpha Plus psyker - one not fully in control of their abilities - was able to destroy a starship, freeze time, put it back together and resurrect its crew from the dead before removing themselves permanently from the physical universe in an act of unparalleled self-control and incredibly heroic self-sacrifice to defend humanity from that psyker’s risk of possession. To dumb it down for the rest of you idiots, that the same as snapping an [[Emperor_Battle_Titan|Imperator Class Titan]] in half with a sneeze at HALF A SECTOR AWAY!  
#'''Alpha / Beta'''
#*Exceedingly rare and dangerous. The Imperium believes that human beings have not sufficiently evolved enough to contain Beta and Alpha levels of psionic talent without going completely batshit mental, though exceptions do exist. [[Arvann Stern]] is confirmed to be Beta-level, and he's not even the most powerful psyker in his chapter. Beta seems to largely be the limit of human sanity, though this is probably fixed with heavy amounts of cybernetics and hypno-indoctrination to make the crazies into useful, if mindless, tools. Most psykers of this power level are considered too dangerous to control and are likely to be sacrificed to power the Astronomican, while ''very'' unlucky Alpha psykers may instead find Imperial service in the Ordo Sinister, meaning they'll get turned into screaming batteries for [[Warlord_Battle_Titan#Warlord-Sinister_Pattern_Battle_Psi-Titan|Psi-Titans]]. The unluckiest Alphas and Betas get to be [[Grey Knights]], and fight daemons until their painful death in battle. The luckiest ones become specialized Astropaths whose predictions of the future are used by the Adeptus Custodes to find threats to Terra.
#'''Gamma / Delta'''
#*Approximately one out of every billion human births will produce a Delta or Gamma level psyker, who, for the Imperium, represent the "useful" upper limit of psychic potential without being too dangerous to let live, though it's up to the [[Inquisition]] to be the ultimate judge of that. Most psykers of this power are either slain or possessed if they are not discovered quickly by the Adeptus Astra Telepathica. The Inquisitor [[Gideon Ravenor]] was believed to be a high Delta-level psyker.
#'''Epsilon / Zeta'''
#*Epsilons and Zetas represent relatively powerful psykers, who are strong enough to be considered threats to security by the Imperium. 
#'''Eta / Theta / Iota'''
#*Iota represents the first "true" psykers who are able to manifest and control psychic abilities with a modicum of training. Anything below this point is not considered a "true" Psyker.
#'''Kappa / Lambda / Mu / Nu / Xi / Omicron'''
#*People who can manifest psychic talents either unconsciously or so subtly as to be beneath the notice of everyone but the Inquisition, such as performing minor "magic" tricks, divinations, or other weird occurrences generally dismissed as good luck. Most of the time they are quite useless, but still represent a danger since they can be possessed. Although the Inquisition is too busy to sort out everyone at this level, the Imperial public is conditioned to spot and ostracize these witches if the truth about them ever comes to light in their societies. Those that do get picked up by the Black Ships are generally considered not worth the risk of training and almost always receive a one-way trip to the Golden Throne to have some sort of use wrung out of them. If you’re power level is low enough, though, even the Inquisition and Black Ships will ignore you as a non-threat.  Which sounds like a damn stupid thing for them to do, really.
#'''Pi / Rho'''
#*Run-of-the-mill humans, neither psy-active nor psy-inert, but indisputably on the positive side because the negatives... get weird.

===Negative Psychic Levels===

#'''Sigma/Tau'''
#*When you start descending below the scale of humans, into the "negative" side of the scale, you start going psy-inert. People at the Sigma/Tau level would be able to perceive and be injured by an incoming fireball but may not be able to discern that it came from an unnatural source. It is believed the entire Tau species rests at this level.
#'''Upsilon / Phi / Chi / Psi''' (ironically)
#*These are individuals with varying degrees of immunity to psychic powers, though not to the same extent as a true Blank or Pariah.
#'''Omega'''
#*Usually referred to as Untouchables, Pariahs, or [[Blank]]s. Not only are they immune to psychic powers, but they can also inhibit the powers of psykers around them and/or neutralize psychic effects on an area around them. The Imperium often employs Blanks as an Inqusitor's servants, while the [[Sisters of Silence]] are a trained order of Psyker-huntresses that are all Blanks. The Eldar, believe it or not, also produce the occasional Blank, and these become the infamous [[Solitaire]]s of the [[Harlequin]]s. True Blanks have such a psy-negative effect that even normal people can sense it, and it manifests as an irrational loathing for the Blank, though in some cases it can be offset by either a good personality (Alizebeth Bequin) or an odd, but explainable character trait (Gunner Jurgen). For psykers however, Omega-level persons are physically and mentally painful to be near. 
#*The fluff is a bit inconsistent on the ''exact'' limit of a Blank's ability, but that's fine, because in [[Dark Heresy Second Edition|Dark Heresy]], Blanks exhibit a broad range of effects which can be different from person to person, much like high-level psykers can have different powers and disciplines. It can also be trained and manipulated, as in the case of the [[Sisters of Silence]]. Others can train themselves to actually benefit from the psychic power they suck from their surroundings (having psykers or even normal living beings in those surroundings really helps), which they use to empower and invigorate themselves.
#*There have, however, been a few occasions where a Blank's abilities have been overwhelmed or even permanently shutdown. Bequin's blankness was overwhelmed by the warp corrupted psi-sentience of a Chaos Titan and Wystan Frauka's blankness was gradually eroded away over time until he was able to be possessed by a psyker. In Gathering Storm, when Khaine's Gate broke, all the strapped and likely sodomized Blanks that were chained to it and had been screaming for the past few decades either exploded into ludicrous gibs or got outright possessed. Alpha Plus Psykers like the Emperor can probably brute force their way through even the most unnaturally powerful blanks.
#'''Omega-Minus'''
#*Strictly limited to [[Culexus]] Assassins, who are given specialized equipment to maximize the effectiveness of their Blank abilities. Another example was an Omega Minus Embryo kept in a stasis jar that was so potent that it killed a Thousand Son's Sorcerer and an Eldar Harlequin just by being near them. 
#'''???'''
#*The Pariah Alpha from Inquisitor: Martyr is a bit of a wild card, since we don't know if there are more like her or what she's capable of. We do know at least their mere presence can [[Wat|truedeath Daemons]]. She might just be an Omega Minus and that rung is beyond the scale like Alpha Plus is, but it's hard to say for sure.

===Other Factors===
When you get further into the details, not only is sheer psychic potential a factor to consider in determining how powerful a psyker is, there are other things to consider when trying to figure out mechanically how one differs from another.

This is easier to do outside of the tabletop setting which focuses on a d6 scale, where a minor difference in a single statistic can create one power tier an order of magnitude more effective above another.

====Level of Control====
The [[Rogue Trader (RPG)|Willpower]], discipline and training ''(read: control)'' of a given individual holds about as much sway as psy-rating in saying who is more powerful than who. Probably because if you can’t use what you have then the excess doesn’t count, and probably also because the Warp responds to will and so willpower can easily become literal power. This is most clearly represented in the RPG rules, but often shows up in the fluff, particularly in instances where powerful but neophyte psykers are only coming to learn their powers ''(such as Da'Kir of the Salamanders or [[Zahariel]] of the First Legion)'' A lot of commentators forget this and focus purely on psy-rating when attempting to compare psychic ability. A psyker may have a high psy-rating but if their ability to control their powers are low then they are less likely to successfully manifest but are more likely to create a powerful effect when they do; this is in fact part of the reason why the Imperium considers them to be so dangerous. Inversely, a low-mid rated psyker with a strong grasp on his abilities is more likely to successfully manifest and is ''also'' more likely to be able to resist/counter incoming psychic effects.

Interestingly enough, even non-psykers with enough discipline and mental fortitude can be trained to resist psychic powers, though this does not mean they are necessarily psychically blunted themselves. Typically this ability comes in the form of intense indoctrination or rote training, or from sheer force of belief and faith to literally "Deny the Witch". It’s unsurprising given the nature of the Warp.

====Sorcery====
The second thing to consider is the whims of the [[Chaos Gods]], (particularly [[Tzeentch]]). '''Sorcery''' is entirely separate from Psy Rating/Assignment and even a non-psyker with the correct rites and incantations can pull off similar ''(but not the same)'' manifestations to a true psyker. Back during the [[Horus Heresy]], [[Erebus]] (and 30k Word Bearers with '''Burning Lore''') was an example of this. Furthermore, although [[Khorne]] himself hates psykers and sorcery, the Daemonancers among his own followers do have access to rituals for summoning daemons; otherwise they would be solely reliant upon tears in the warp for receiving daemonic assistance. These ritualistic functions ''may'' have been carried over to 8th edition where every chaos character now has the ability to summon daemons ''(though this could just as plausibly be the champion calling out to his God and being rewarded with assistance while in a location where the realspace/warp barriers are thin or have already been broken)''

A true psyker with access to sorcery can increase his power levels even higher and can easily outstrip more powerful psykers than himself, though Sorcery comes with its own perils and generally leads to Damnation and Corruption ''(no wonder big Emps put his foot down at the council of Nikaea)'' not to mention the idiocy of increasing your psychic power beyond what you can control.

Furthermore, certain favours gifted from the Gods also increase psychic output. It used to be that in days gone by, the '''Mark of Tzeentch''' used to enhance psychic potential on the tabletop. [[RAGE|Nowadays it doesn't]], but in the RPG it still does. But obviously once you've been marked by a God of Chaos, you're in their pocket forever, and you best do your utmost to keep them happy or you end up becoming [[Chaos Spawn|that-which-shall-not-be-named.]]

====Pushing====
Separate from either issue is the fact that Psykers can theoretically increase their assignment rating for a brief instant, drawing surplus energies from the warp and ''"Pushing"'' their powers even further than should be possible, basically taking a gamble and temporarily adding MOAR power to their manifestation. 

In both the rules and the fluff there are common instances of psykers being able to boost themselves and create larger effects or to overcome more powerful opponents. This was partially illustrated with the 7th Edition ruleset and the shared Warp Charge "Pool", where low level psykers could throw all available warp charges into a single power and overcome the abilities of a higher mastery opponent, albeit at considerable risk of Perils of the Warp. 

However, not all psykers have the ability to do this to the same degree, and although not adequately shown on the tabletop such rules were presented in the RPG settings, which broadly fit the established fluff:
*'''Bound Psykers,''' that is to say, nearly every Imperial psyker who has undergone a Sanctioning process [Including Librarians] or Soul-Binding can only push themselves so much and they are at greater risk of something bad happening (ie Perils of the Warp) when they do so. Specifically, Soul-Binding to the Emperor includes all Astropaths and the psykers who lack the willpower to be safely trained but have too much power to be waste.
*'''Unbound Psykers''' ''(Rogue Psykers / Sorcerers)'' on the other hand can push to even higher degrees of power but [[Not as Planned|shit WILL hit the fan]] and can almost guarantee their manifested power will come with some form of [[Chaos Spawn|unintended side effect]] when they do.
*'''Daemonic Psykers''' who attempt to push their powers can go yet higher, but are considerably more likely to cause dangerous psychic phenomena. However since their mere existence on the material plane can be considered a dangerous psychic phenomena they are less likely to be bothered by it unless it is a straight up Perils of the Warp.