Emotional distress during casting is not recommended. A lack of focus reduces precision and directional bias, causing conditioned states to collapse and relaxes into Arkhé — which then directs it back into the neural network of the caster, essentially frying it. This happens due to the caster having been the instrument to generate the bias.

What the caster actually does.
Phos and Skotos are directional pressures applied to atomic structure through various methods;

✧Phos
increases binding energy between atoms. When a caster applies structural pressure, they are forcing electrons deeper into stable orbital configurations — making atoms lock together more firmly, in more ordered arrangements. The result is increased rigidity and structure.

✧Skotos
decreases binding energy. When a caster applies decaying pressure, they are forcing atomic bonds to release the energy stored within them. That energy erupts outward as heat, kinetic force, electrical discharge, or decay.

Both are manipulations of existing matter and neither creates anything from nothing. A caster cannot produce conventional elemental effects without matter to manipulate for there is nothing to apply pressure to. They are techniques when used and energy labels when the process is completed.

Casters do not all interact with atomic structure the same way. Two broad cognitive styles have been observed, both having their own strengths and drawbacks.

✧Depictive casters
sometimes called Visualisers — perceive the spell spatially. They hold a mental image of the target state and apply pressure toward it. This works well for elements with imaginable end-states: a closed wound or spreading flame. Visualisers are fast and intuitive, but their precision is bounded by what they can picture. Elements that require targeting invisible substructure — electron orbitals, bond dissociation constants — cannot be adequately imagined and only approximated. Approximations at that scale are lethal. Visualisers are also more vulnerable to Phos Mania; an overconfident mental image can overwhelm the technical ratio.

✧Propositional casters
often aphantasic — do not perceive spatially. Instead, they experience Aetheric Synesthesia: a cross-wiring of senses that renders atomic configurations as sound, pressure, temperature or taste. Where a Visualiser sees the hexagonal ice lattice, a propositional caster feels the bond angle tighten or hears the molecular frequency shift toward its crystalline state. It is by far the most reliable way to interact with structure too small to see.

Visualisers may also experience synesthesia, but their cognition prioritises spatial imagery over raw sensory data. Propositional casters rely on synesthesia as their primary — sometimes only — interface with Aether.

Visualisers are faster in fluid combat; propositional casters are safer with high-risk elements.

Sometimes, an individual may not be aphantasic but in most cases the brain prioritises the safest way to execute the spells.

"Conditioned Arkhé" when channelled by humans, burns them from within and stops their hearts and brain. When channelled by Valkyrs, it can corrupt and crystallise them unless handled with extreme skill. Bul'ar, though constitutionally resistant, are not immune: channelling Phos or Skotos from within can still harm them if highly-conditioned and handled in massive quantities. Phos/Skotos introduce directionality and imbalance that disrupt Arkhé-encoded identity.
The effects vary depending on how energy is introduced:

✧Consumption of Valkyr supplies
Food or rations infused with Phos or Skotos—designed to sustain Valkyrs and Human casters—turn harmful to Bul'ar physiology. Their bodies reject the imbalance, resulting in disorientation, or temporary weakness. Rarely fatal, but debilitating enough to cripple them on the battlefield momentarily. It may also affect their preferred element when ingested long-term and swap their appearance.

✧Casting Phos/Skotos
When a Bul'ar draws upon refined Phos or Skotos in extremely significant measure, they force a divided flow into channels meant only for Arkhé. The imbalance shatters their equilibrium, may corrupt their matter and in some cases shatter the core.

Modern society has formed itself around the ability to manipulate Aether and over time, ranks to begun to form. These ranks would affect career prospects and even disciplines:

✧Untrained and unskilled
Those who cannot control Aether and lack the academic ability to study it.

✧Practitioners without understanding
Individuals who can manipulate Aether but lack the theoretical knowledge to advance their abilities significantly.

✧Valkyr with limited mastery
Those who have crossed the threshold required for immortality but fail to develop a deep understanding of how to fully manipulate matter.

✧Elite Valkyr
Individuals who possess both exceptional control over Aether and the academic insight to apply it creatively and effectively.

Each tier carries distinct social status, opportunities, and responsibilities, shaping the hierarchy of factions and legions across Etherion.

Priests and skilled healers can administer precise, minute doses of Phos or Skotos to regulate the body’s natural gradients. This practice is often used for:

✧Infants born with unstable energetic regulation near the immortality boundary
A tiny adjustment in energy can normalise development and ensure they age at a healthy rate.

✧Recovering Valkyrs or Humans after trauma
To restore energy equilibrium and prevent corruption or exhaustion from overexposure to Phos or Skotos.

✧Aether-sensitive treatments
For ailments caused by energy imbalance, including stunted growth, weakened bodies or energy-related sickness.

Doses are extremely precise: too little has no effect, while too much risks disrupting the individual’s natural energy flows, potentially leading to death or illness. In rare cases, misuse has catastrophically pushed a patient past the threshold toward immortality.

Cases of individuals born with an innate capacity to separate Phos and Skotos are extremely rare. When they occur, they are associated with abnormal energetic development during gestation, often linked to Valkyr lineage or failed stabilisations attempts. No such cases are recorded prior to the widespread creation of Valkyrs.

Certain regions contain unnaturally dense concentrations of Aether. Depending on whether the local flow leans toward Phos, Skotos or nearly relaxes into Arkhé this buildup can warp the environment and trigger natural disasters:

✧In the skies
Sudden surges of Aether mingle with clouds, sparking violent thunderstorms or lightning storms.

✧In the seas
Concentrations of energy disturb currents, causing floods or worse.

✧On land
Local imbalance may twist plant growth, cause sudden decay or destabilise the ground into fissures and landslides.

Because of their volatility, many of these areas are declared off-limits by governments. However, their isolation and instability make them havens for rogue factions or smugglers who exploit the dangerous terrain to conduct their affairs beyond the reach of law.

Aether in environment is known to affect people's mental states.

Originally, scholars argued that the energy found within Yggdrasil and all over Etherion should be called Hagnos, as it was considered holy and pure by many.

However, since the Bul'ar excelled at manipulating this energy, some disagreed with labelling it as “pure” and instead proposed the term Arkhé.

King Óðinn of the Svartálfr noticed elements near the Creator sometimes would show atoms in readable minor forms through runes, which the seeresses of the Svartálfr were carving into dolls and tossing them into a well nearby the Creator.

Synesthesia is a big part in Valkyr and Human lives — a neurological condition where the brain gains access to atomic-scale information through unconventional senses (vibration, taste, scent, pressure).

Brains evolved to detect Aether over time, allowing Humans to manipulate elements beyond the primary ones. Depictive casting (visualisation) fails for ice/lightning because you can't see electron orbitals. But if you can taste bond angles or hear atomic vibrations suddenly precision is possible.

Aetheric synesthesia acts as a sensory interface, knowledge acts as an instruction set, focus acts as an actuator and finally; practise allows for automation — allowing people to cast the elements as if it was simple instrument play.

The Aetherstream, also called the flow of Aether, is the road among which all conditioned Aether travels towards Yggdrasil to be cleansed by the tree and exerted by it.

All known Aether, be it from an exhaled breathe or a pattern of a deceased individual, travel through this stream.