Amendment
Aura: Semblances
a¡po¡thym¡e¡tics /ËĂŚpÉθɪËmÉtÉŞcs/ n. the study of Semblances. [Ancient Greek áźĎÎż (apĂł), apo-, derived from, + θῥΟĎĎ (thĹŤmĂłs), -thym-, soul, + ΚκĎĎ (ikĂłs), -ics, pertaining to]
Introduction
If Aura is the physical manifestation of a personâs soul, then a Semblance is the form that manifestation takes. Apothymetics, the study of Semblances, is a subdiscipline of pneumatophysics (the study of Aura). Broadly speaking, a Semblance is a skill or ability that enhances or transcends a personâs biological limits. These abilities draw upon a personâs Aura reservoir as their source of power, and over time, that reservoir is gradually depleted through usage. Scientists and historians alike attribute the advent of Semblances, along with the discovery of Dust, as the catalyst that turned the tide in the abiding conflict against the Grimm, and brought humanity back from the brink of extinction. Semblances are widely regarded by researchers as pneumatophysical adaptationsâevolutionary responses of the soul as a result of Grimm predation. The staggering variety of Semblances supports this claim, as the diversity of Grimm would have created the necessary selection pressures to trigger a similar apothymetic diversity in humans and Faunus.
Despite numerous scientific advances made in the last few decades, even some of the most fundamental questions about Semblances remain unanswered. Pneumatophysics, along with rhizology (the study of Dust) and archotherology (the study of Grimm), belong to a group of sciences historically known as the Profaned Arts. As recently as three centuries ago, academic inquiries into any of the aforementioned topics were considered stigmatized at best, heretical or blasphemous at worst. All three subjects directly or indirectly pertain to the soul, and thus formed a recurring pancultural trinity throughout Remnantâs past. Pervasive superstition and religious influence often stymied scientific progress, and in some cases this crusade took on more extreme forms, such as destroying physical research, or executing the people that conducted it. While a decreased religiosity led to paradigm shifts in modern culture, the influences of past stigma can still be felt across the four kingdoms where soul research is concerned. In particular, the Kingdom of Atlas, the worldâs foremost leader in pneumatophysics, still receives criticism from those who feel that its work sacrifices ethical constraints in favor of âmutilatingâ the soul.
Estimates on just how many people have discovered their Semblance are notoriously vague. Census data compiled over the last century (starting ca. 2 AB) suggest numbers from as few as 0.25% to 4% (875,000â14,000,000) of the global population, though pneumatophysicists point out that this figure could be substantially lower. Predicting which demographics are most likely to have Semblances is an imprecise measure at best; that being said, Huntsmen, and people living in extraregnal settlements, tend to disproportionately have higher-than-average Semblance discovery rates.
Activation Criteria and Auratic Plasticity
The only prerequisite for discovering oneâs Semblance is to have an unlocked Aura. Very seldomly, a person may simultaneously unlock both their Aura and their Semblance, under extreme conditions.
The pathway to unlocking oneâs Semblance, while outwardly unpredictable, does seem to be determined by certain factors. Intensive, routine physical activity tends to be the most reliable way to trigger Semblance discovery, although intense emotions have been suggested as another. The type of Semblance a person has, and the circumstances under which itâs gained, are dictated by a mechanism called Auratic plasticity. Auratic plasticity is the ability of the soul to generate a Semblance based on either an individualâs personality (innate), a scenario-specific survival method (adaptive), or a âgeneticâ trait thatâs repeatedly selected for due to its âinherent fitnessâ (inherited). These three categories are determined by a variable called hierarchical prioritizationâthe soulâs ability to decide which Semblance-trigger gets precedence.
Itâs agreed by the scientific community that thereâs an order to Semblance-triggers: inherited > innate > adaptive.
If, for example, a person hailed from a lineage of summoning Semblances, then that person would acquire summoning by default. When a person doesnât come from a family of inherited Semblances, then they would receive an innate Semblance that aligns with their nature. The last type of Semblance-trigger, adaptive, only occurs when a person is confronted with a life-or-death scenario, and the soul âoverridesâ the default order to generate a reactionary Semblance tailored to their immediate survival. In the case of an adaptive trigger, a person from a line of summoners could gain an unrelated Semblance, and break the chain.
The discoverer of these mechanisms, Ilere Koya-Hark, famously tested their theory when they went out into a thunderstorm, and induced an electrokinetic Semblance. This experiment laid the groundwork for what would become the field of dilonometry.
It should be noted that any Semblance can be innate, adaptive, or hereditary. Thereâs no distinction between a hydrokinetic Semblance inherited over generations, or a hydrokinetic Semblance that emerged in response to a near-drowning.
While adaptive and hereditary Semblances are easy enough to understand, innate Semblances are a little trickier. Researchers agree that innate Semblances in some way relate to oneâs personality, but itâs debated to what extentâwhether a Semblance pertains to a singular, immutable trait, or to oneâs overall disposition. And even then, itâs hard to define what, exactly, an innate Semblance says about its user. Does a speed Semblance always mean that a person is hasty? Can it be interpreted as someone whoâs limitlessly altruistic, and rushes to othersâ aid? Or perhaps it signifies a person thatâs energetic and enthusiastic. If innate Semblances can represent multiple traits, then two people with the same Semblance might have drastically different, overall personalities, further muddying the debate.
For now, the consensus is that an innate Semblance is in some way a reflection of oneâs soul. Anything more specific than that typically devolves into arguments and fistfights.
Categorization
Itâs been disputed just how many Semblances there actually are, and how best to go about divvying them up into neat, consistent headings. At multiple points throughout history, the very idea that Semblances could even be organized into categories was debated, under the belief that âno two Semblances are alike.â This mindset stemmed from a philosophical approach rather than a scientific one, rooted in the idea that souls were so unique as to not be identical, and therefore neither could their Semblances.
Of course, with the benefit of hindsight, thatâs not actually the case.
The system currently used for classifying Semblances was devised by Cerise Maida, the archivist of Fort Nubuck, roughly seven decades ago. There are 14 recognized categories each defined by unifying criteria, such as how their powers are expressed, or how they affect the world around them. While far from a perfect system (and not without its criticisms), itâs helped streamline the process for identifying Semblances. More importantly, it allowed apothymeticists to not only clarify what Semblances can do, but what they canât do.
Absorption Defined as the ability to store physical damage as a form of potential energy, and later release it in a single burst. As the userâs Aura shielding sustains damage, the depletion of their reservoir is âconvertedâ into a latent power that increases over time. This buildup is proportionate to the damage that the user receives. When released, the gathered energy is channeled into a motionâsuch as a kick or a punchâthat drastically amplifies the impact behind the next attack. With enough buildup, a skilled practitioner can deplete an opponentâs Aura in a single hit.
Alteration Defined as the ability to temporarily alter certain qualities of matter, such as temperature, color, tangibility, volume, and opacity. The effects of alteration Semblances can either be self-imposed or directed upon another person or object, once the user initiates contact.
Cloaking Defined as the ability to conceal oneself from the Grimm. There are two varieties of this Semblance: Aura-cloaking and emotion-cloaking. Each has the ability to interfere with a Grimmâs two primary senses (pneumatoception and algeaception), by masking either a personâs Aura signature or their emotional state. Although highly effective against lower-ranking Grimm, the success rate tends to decrease against more dangerous species. Ideally, the Grimm becomes âblindâ to the user and cannot distinguish them from ambient sensory data. Under less ideal conditions, a Grimm becomes alerted to the userâs presence but canât pinpoint their exact location.
Elemental or Kinetic Defined as the ability to generate or manipulate certain expressions of matter/forces. This category contains a diverse range of elemental powers, with common examples including pyrokinesis (fire), hydrokinesis (water), gyrokinesis (gravity), ferrokinesis (metal), electrokinesis (electricity), terrakinesis (earth), and aerokinesis (wind).
Enhancement Defined as the ability to exaggerate or heighten certain physical attributes to an otherwise superhuman level, such as speed, strength, or endurance.
Illusory Defined as the ability to create visual illusions. This power calls false images into existence and projects them into the userâs surroundings. Although these illusions are of a high fidelity, theyâre intangible, and lack the mass necessary to be interacted with. With training, the user can increase the complexity or scope of their illusion, and even selectively choose who can or canât perceive it.
Interference or Modification Defined as the ability to influence another personâs Aura. There are several recognized varieties of this Semblance-typeâamplification, bypass, transfer, and suppressionâthat each directly modifies the targetâs Aura when the user touches them. Amplification Semblances allow the user to donate Aura to a recipient from their own reservoir. Bypass Semblances enable the user to disable their targetâs Aura shielding. Transfer Semblances allow the user to redistribute Aura between multiple people, by acting as a conduit. Suppression Semblances nullify the targetâs Semblance for a brief window of time.
Manifestation Defined as the ability to physically manifest a personâs Aura as extensions of multiple body parts. When activated, the user envelops their limb in an Aura âsheathâ that then assumes the function of that body part. From there, the Aura sheath can be manipulated to perform various functions. Examples include forming long, whip-like tendrils that extend from the shoulders, or sharp spines on the soles of oneâs feet for traction or increased stability.
Metaphysical Defined as the ability to interfere with the mind. Statistically the rarest Semblances, this heading is often regarded by apothymeticists as a âwastebasketâ because of how dissimilar many of the Semblances in this category are from one another. Each interacts with a foreign psyche in some way, be it remote communication (telepathy), temporary episodic wiping (memory repression), or polygraphic intuition (lie detection).
Mimetic Defined as the ability to perfectly mimic body movements and speech patterns observed in others. This Semblance-type is unique in that it doesnât require the user to have any prior experience in the actions theyâre attempting to replicate. A person with no gymnastic training, for example, can still accurately mimic the backflips they once watched someone else perform. This temporary skill acquisition can let the user do things as mundane as copy another personâs handwriting, or imitate an unfamiliar accent.
Probability Defined as the ability to manipulate variables within oneâs immediate surroundings to create cause-and-effect changes that either directly benefit the user, or disadvantage others. Also informally known as âluckâ Semblances, these are by far the hardest to study in any capacity, given the sometimes-random nature of their effects.
Replication Defined as the ability to create copies, or âshades,â of oneself. Considered one of the more demanding Semblances to master due to its higher Aura requirements, but itâs undeniably powerful to have. The user sacrifices a chunk of their Aura and imparts it upon a copy of themself. Although the copy doesnât have the ability to use Aura, it does have some considerable bulk and can withstand a specific amount of damage before being destroyed. Copies retain physical mass and are visually identical to their user, making them useful for ganging up on opponents, or deceiving them. Skilled replication users can create an upward number of nine copies; anything beyond that has never been recorded.
Summoning Defined as the ability to conjure apparitions, or thralls, of Grimm that have been defeated before. These spectral creatures share a link with their summoner, and will act in accordance with the userâs will. The userâs proficiency dictates both how many thralls they can summon at once, and what species theyâre able to conjure.
Teleportation Defined as the ability to transport a person between locations at will. In order for this Semblance to work, it requires the user to have physically visited the destination at least once before.
Alteration, elemental, replication, and enhancement Semblances are the most commonly-occurring. By contrast, illusory, interference, probability, and metaphysical make up an extremely small percentage of unlocked Semblances.
Active versus Passive Semblances
Itâs a generally-accepted fact that Semblances require conscious choice on the part of the user. That being said, there are cases where a person doesnât always get a say.
The term passive refers to any Semblance that is involuntarily engaged, and runs in the background at a much lesser intensity. Studying them has been notoriously difficult to do, in part due to their rarity and the stigma associated with them. While technically any Semblance can be passive, in theory, certain categories disproportionately represent that number (namely elemental, cloaking, alteration, and probability).
Itâs not well understood what causes a Semblance to be passive as opposed to active. One tentative study found a potential correlation, where age and environment were considered factors. A number of study participants who had passive Semblances either unlocked theirs when they were younger (< 9 years old), or as they grew up in unstable home environments. Given the lack of childhood autonomy, itâs been suggested that passive Semblances are formed during adolescence as a coping response to stress.
Just like an active Semblance, a passive Semblance requires Aura in order to function. In exchange for being constantly running, passive Semblances deplete Aura at a significantly decreased rate, and their effects are disproportionately âlesserâ than those of active Semblances. With training, a person with a passive Semblance can learn to âdirectâ it and momentarily bolster its effects.
The impact of a passive Semblance on a personâs quality of life can range from mildly inconvenient to outright debilitating. Some individuals manage by tailoring their daily lives to accommodate their Semblances, whereas others resort to cataspin to keep their Auras (and thus, their Semblances) in a permanently-suppressed state. Doctors typically advise against the latter due to potential negative side effects.
For those reasons, passive Semblances are generally considered a disability.
Limitations
While Semblances can push the boundaries of natural laws, they too are beholden to limitations. Known as Maidaâs Four Laws, these limits were described shortly after the establishment of the Semblance category system.
They are defined as such:
A Semblance is restricted to one per person.
A Semblance cannot be used without Aura. If a userâs Aura is inactive, depleted, or suppressed, then the Semblance will fail to work.
A Semblance, once manifested into its current power, cannot change.
A Semblance cannot transfigure a userâs form, or convert matter into a new substance.
Needless to say, these laws have been indispensable to pneumatophysicists in debunking previously-accepted historical accounts. Claims of people transmuting objects into gold were attributed to alteration Semblances, that temporarily made objects gold-colored. Other claims of Semblances turning people into animals were dismissed as folklore.
Similarly, the myth of those with multiple elemental Semblances are now seen as exactly thatâa myth.
Regulation and Legal Oversight
Compared to post-war legislation, older laws were far more restrictive.
One such example included the impositions of the Mistrali Empire, which expressly forbade private citizens from unlocking their Aura. Anyone found to have done soâwhether accidentally or intentionallyâwas either forced to enlist (as a guard, ranger, or soldier); was required to pay a monthly tax; or had to take medicine made from Aura-suppressing bellicyclate-rich plants, prescribed by a state-authorized physician.
These measures were meant to serve as deterrents, and discourage anyone from activating their Aura (and by extension, their Semblance). The explanation given under imperial law was to preempt Grimm aggression and encroachment, by reducing the amount of stimuli that their pneumatoception could perceive. Itâs been proven that Grimm do, in fact, prioritize targets with unlocked Auras over targets with dormant ones, and that Aura signatures more strongly attract them.
However, historians now accept that the then-given reason was a guise. The Mistrali Empire likely implemented these measures to prevent secessionists from gaining a means to fight back. While anti-Aura and anti-Semblance restrictions werenât unheard of in other polities, Mistralâs were undisputedly the most authoritarian.
International law passed during the Vytal Summit guarantees considerably more freedoms, regarding oneâs Aura. The ability to pursue Semblance-acquisition is considered an inalienable right, and no person may be penalized for doing so. Likewise, Semblance disclosure is considered voluntary (and in many places, is reinforced by cultural taboo). The only demographics legally required to do so are academy students and licensed alumni, who must register their Semblance with their alma mater. Individuals employed in a military or law enforcement role are held to the same standard.
The only time when private citizens are required to disclose the existence of their Semblance is when theyâre arrested for criminal charges.
In Non-Humanoid Species
Although all animals have the ability to unlock their Aura, only two species (humans and Faunus) have been observed using Semblances. Researchers in the field of pneumatozoology have suggested that itâs theoretically possible, although itâs not currently known what criteriaâif anyâis needed to achieve this.
Reception to the idea of animals with Semblances is mixed. Some groups, like Huntsmen, favor the possibility of using a familiar with increased combat aptitude. Itâs this same combat aptitude which also garners detractors, who fear that an animal with a Semblance could become a nuisance or a hazard.
For better or worse, apothymetic laws have yet to preclude the possibility.

















