Psionics

Psionics, or psychic powers, is the use of psionic energy from the parallel dimension of the Umbra, a shadow of the physical world and repository of all the psychic energies of the galaxy. Those who are connected to the Umbra and able to draw upon its energies are most commonly known as psykers, and can make use of all manner of unusual powers, ranging from telepathy to matter manipulation to temporal distortions. Opinions on psykers and psionics vary greatly across the galaxy. On some worlds, psykers are lauded as gifted and treated with reverence, while on others, they are loathed, feared, or even hunted, decried as witches and demons. Most commonly, however, psykers are viewed through the lense of science, and efforts are made to both study and make use of their powers by numerous governments throughout the galaxy.

Mechanics of Psychic Power Usage
When a psyker makes use of their power, they draw upon their connection to the Umbra, and channel its energies into themselves, and thence, direct them out into the physical world, the minds of other beings, or elsewhere. When channeling psionic power into their physical surroundings, a psyker's body is used as a conduit, leaving their cells (or mechanical components, as they case may be) charged with psionic energy, and producing a telltale surge of power that can be sensed by other psychic individuals or psionically sensitive equipment.

What exact effect the psionic energies exert depends on the mind of the user. Will and concentration is used to focus and direct a psyker's power in order to bring about the desired effect. However, given that the sentient mind is prone to distraction and emotional turbulence, training and practice is required for most psykers to be able to consistently use their powers in a controlled manner. While psionic abilities fueled by raw emotion and unfocused will can be potent, especially for those with a strong connection to the Umbra, the powers such an untrained individual wields will be uncontrolled and sporadic, and will often manifest in moments of extreme emotion.

For this reason, most psykers undergo years of training to hone their mental discipline in order to master their abilities. Many psykers over the millennia have devised all manner of rituals, special items, and symbols which they used to concentrate themselves. Among many psychic order, these tools are known as foci. Over time, the effort a psyker puts into devising foci coalesces within the Umbra, and creates a wellspring of mental intent that they and others can draw on to ensure that the use of a focus always results in the effect it was originally paired with. This allows a psyker to learn numerous techniques from various psychic orders, studying their disparate practices in order to replicate that organization's unique manifestation of psychic power.

Psyxanthellae
Psyxanthellae are microorganisms which feed on psychic energy. When introduced to a multicellular organism, they tend to live in the edges of their cells, absorbing minimal amounts of psychic power to sustain themselves. If sufficient psychic energy is outputted from the cell they are attached to, they will begin to multiply until reaching numbers that can sustainably survive off the outputted energy. For this reason, psyxanthellae that are injected into a psyker can serve as an indicator of how much psychic energy they are producing. Regular use of psionic powers by a psyxanthellae host leaves trace amounts of psionic energy within their cells that the psyxanthellae can feed on. Naturally, the more power used, the more is left over. However, should a psyker abstain from using their abilities, the lingering psionic power in their tissues will dwindle, causing psyxanthellae populations to decline.

Psyker Powers
Psychic individuals can, with talent or training, sense the psionic presence of other psykers. They are able to roughly gauge the power level of the psyker who they are scanning, with more potent psykers being much more easy to detect. Trained psykers are also able to detect the use of certain psychic powers that are used in close proximity to them, and most every use of ones abilities makes it easier for their psychic presence to be detected.

Psi-Scanners
Certain races and factions who employ psychic technology are possessed of devices known as Psi-Scanners, that enable them to precisely calculate psychic energy wherever it is emitted. The most common unit of measure found on a Psi-Scanner is known as the kili. Psi-Scanners themselves rely on psionic energy to power them, though many models exist which can be used by those who are not psychically attuned, so long as the scanner has previously been charged.

Kilis are emitted any instance a psyker projects psionic energy which alters the nearby physical environment in some way, be it through a feat of telekinesis, opening a portal, or emitting a blast of psychic fire. Telepathic abilities do not register on Psi-Scanners, it should be noted. Low level kili emissions of one kili might include telekinetically lifting a small object, or conjuring sparks of electricity from one's finger. A ten kili emission could entail a blast of force that flattens a body into pulp, while a fifty kili power surge could incite an explosion that destroys a small building. The largest ever recorded emission, which produced some ten thousand kilis, resulted in an entire planet being blasted apart.

Kili readings can also be found in psychic nexuses, locations throughout the galaxy that are filled with psionic energy.

The Glumini Scale
Developed as the atrocities of the Lorgalian Cataclysm raged across the galaxy, the Glumini Scale was devised by Grand Admiral Maralda Glumini, for the purpose of classifying psionic individuals based upon the threat that they pose. Psykers with powers that were deemed less dangerous, weaker, or more easily controlled ranked lower on the scale, whilst higher levels were assigned to psychic individuals whose abilities expressed themselves as more potent, volatile, and potentially harmful to those around them. A psyker's assignment on the Glumini Scale could be raised or lowered depending on the development of their abilities. If they became more powerful and destructive over time, the psyker might be assigned a higher ranking, whilst if they were weakened through the use of a Yoreldo implant, the psyker's rating might be lowered.

The number ratings of the Glumini Scale are paired with a corresponding threat class, with higher numbers resulting in placement in a higher threat class. The classes and their corresponding numbers, from lowest to highest, go thusly: Zeta (0), Iota (1-2), Epsilon (3-5), Delta (6-9), Gamma (10-14), Beta(15-17), Alpha (18-20), Omega (21+). Zeta Class entails that an individual has no ability to use psionic abilities, while an Iota Class psyker generally can make subconcsious use of psychic powers, and might be able to sense the use of psionics in their vicinity but never make use of abilities as overt as employing telekinesis or firing lightning from their fingers. Epsilon and subsequent classes can manifest various psionic abilities, which grow more potent as one moves up the classes. Epsilon Class psykers can manifest some formidable powers, but are not usually extreme threats, while Beta and Alpha level psykers can be a danger to large level populations, and are usually viewed as extremely dangerous and highly unstable. When a psyker reaches Omega level, they are deemed an absolute threat, and wield power enough to destroy planets single handedly.

Zeraphan Mages
Main Article: Zeraphan Mages

The Zeraphan Mages, before they withdrew into the Umbra during the Lorgalian Cataclysm, were one of the most powerful psychic orders within the galaxy. Possessed of one of the most thorough and expansive training regimes for mastering psychic power, their purpose was long to study every aspect of the psychic mystery, so that the knowledge they gained might be used for the betterment of themselves and others throughout the galaxy. To this day, no other faction has attained the same level of understanding as the Zeraphan have into the nature of the Umbra and the powers that extend from it.