Mana

Mana is the most abundant of the energies that comprises the Nether Realm, especially the Astral Plane, and trickles into the material universe. Mana is what allows magic and psychic power to function, and makes magic technology viable.
In the nether, mana is in its volatile, raw form, typically called "indigo mana." In this form, it can be most easily manipulated. Indigo mana is said to "flow through the astral plane like water through the ocean." However, indigo mana cannot exist uncrystallized in the material realm. Upon entering the material universe, it spontaneously converts to a different "color," depending on what it is exposed to upon entry. Earth's mana temples, mana power plants, and mana factories are able to significantly increase the amount of mana pulled into reality, as well as purposefully convert it into the desired color.
Naturally, mana is very sparse in the material universe. It appears most frequently around stars and black holes, though planets with abundant life have relatively large amounts, as well. Still, without deliberate suffusion, mana is too dispersed to be able to perform magic, perhaps allowing for sporadic uses of cantrips or the wasteful use of level 1 spells. At natural levels, magitech wouldn't be viable, as the amount of energy needed wouldn't be available.
Mana exists in the environment (unless contained in crystal form). The amount of mana (1 unit is called a "mote") in an area has both a maximum and equilibrium amount. Mana will settle into its equilibrium if nothing interacts with it; excess mana disperses to other areas, and deficit mana will be drawn from neighboring areas, similar to air filling a vacuum. On Earth, the average maximum amount of mana a tile (a 3×3×3 hexagonal space) can hold is typically 10 motes, and so any area in-game holds a maximum amount equal to 10 × the number of tiles in the zone.
An area's equilibrium will usually be about 60% of its maximum. The color of mana is irrelevant as far as filling it; one color is as good as any other, though if nothing artificially adds mana, it will usually have a default set of colors. An area will shed excess mana, 4 per round if at 100%, 3 per round if between 86% and 99%, 2 per round if between 71% and 85%, and 1 per round between 61% and 70%. If it is below its equilibrium, it will draw in 1-2 mana per round between 45% and 59%, 2-4 between 30% and 44%, 4-7 between 10% and 29%, 7-12 between 1% and 9%, and 13 motes if at 0%. This principle holds true on other planets, where their maximums are lower; if above about 60% capacity, they shed mana, and if below they try to draw it in. Note, though, that an area will never draw in more mana than it can hold at maximum in a given turn.
Whenever a spell is cast, motes of mana are consumed from the surrounding area, the amount equal to [spell's level + 1]. All spells require specific colors of mana; if a mage casts a spell when one or more of the required colors isn't present, they must expend 1 SL to convert another color, though mages with the Ki to Mana talent may expend CP instead. While mana is abundant on Earth, it can be consumed faster than it is replenished if large amounts of high-level magic are used in a short period of time.

Mana on Other Planets

The mana temples, as well as myriad mana power plants and factories, allow enough mana to be present on Earth to permit large amounts of magitech and great quantities of mages. It is also what allows those born with the psychic gene to harness their powers. Because Earth's manasphere (the radius around Earth in which its mana is practically useable) extends beyond the moon, certain structures that are intended to be as bereft of mana as possible must be built on neighboring worlds, namely Bastion's End, the psychic concentration camp on the planet Vinus. Because of the great distance, Earth's manasphere has only a negligible effect on the amount of mana on Vinus, and only when the two planets are at their closest. Within Bastion's End, mana is always at 0, but elsewhere on Vinus, it has a maximum of 1 mote per 30 tiles.
On the other hand, there are two lunar colonies, Spaceport Tidegrasp on Luna's north pole and Spaceport Zukiyomi near its south pole. They receive enough mana from Earth that a smaller mana factory in each is sufficient, though plans to build a power plant on Luna are in the works. While this does generate enough mana for magic to be utilized regularly, mages of all types are viewed with additional suspicion while on the moon. These spaceports have a similar density of mana to Earth. Outside of the spaceports, Luna tends to have a maximum of 9 motes of mana per tile.
Furthermore, astronauts trying to colonize Mars have constructed the colony of Muskfall, though they needed to first create a mana power plant to do so, all of which was a difficult prospect due to the cosmic force field the mana temples generate around Earth. Due to the limited amount of mana on Mars, magic is restricted to only those willing to use clunky mana crystals. Within Muskfall, mana maximum is 5 motes per tile, but otherwise, Mars has a maximum of 1 mote per 12 tiles.
Extremely expensive and complicated interplanetary portals are used to reach Bastion's End (which is strictly policed and guarded by a powerful devil) and Muskfall. While access to Bastion's End is extremely restricted, Muskfall has begun allowing tourists, though the price of travel is currently prohibitively expensive, even while being subsidized by the Wayfarers' Guild.
These alien power plants allow a limited degree of terraforming, making living on the alien worlds plausible. Similar structures were created on the lost planets Laxra, Harmis Prime, and Sinek, as well as throughout the Milky Way thanks to the all-but-extinct Testers. However, it is unknown if these sources of mana still exist anymore.

Mana Colors

Because of its volatility, mana changes its color upon interacting with the material universe. Generally, mana changes into a color based on what it is passing through upon arrival, but in cases where it may be passing through more than one thing, it has a tendency to favor converting to some colors more than others. All colors of mana are useful (with indigo being the most if it were more accessible), though some are in more demand than others. The below list is presented in order of precedence, from most to least likely to occur given multiple possibilities.

White Mana

White mana manifests in the presence of electricity, magnetic fields, and light with visible or shorter wavelengths. On Earth, the guardian of the white mana temple is the dragon goddess Amanafre. White mana is used for any devices that need electricity to run and is often called on for electrical and some healing spells.

Red Mana

Red mana manifests in the presence of heat, light in the infrared or longer wavelength range, and non-gamma radiation. On Earth, the guardian of the red mana temple is the dragon god Vaxdalro. Red mana is most commonly used for fire magic or to amp up spells via Empower and Maximize metamagic, but some rudimentary heating sources use red mana in place of white mana.

Violet Mana

Violet mana manifests in the presence of toxins, some radiation, acidic and alkaline substances, and dead organic matter. On Earth, the guardian of the violet mana temple is the dragon god Mookana. Violet magic is used for spells that inflict poisons and diseases, as well as spells that raise creatures into undeath.

Green Mana

Green mana manifests in the presence of organic lifeforms. On Earth, the guardian of the green mana temple is the dragon goddess Sereter. It is most commonly used for healing spells and spells that amplify physical traits.

Orange Mana

Orange mana manifests in the presence of solid matter. On Earth, the guardian of the orange mana temple is the dragon goddess Acha. Orange mana is used commonly by runescribes to endow objects with magical properties but is also used in spells that transmute matter.

Blue Mana

Blue mana manifests in the presence of liquid matter. On Earth, the guardian of the blue mana temple is the dragon god Asmoni. Blue mana is rarely used in healing spells but is commonly used to cast ice-based magic.

Yellow Mana

Yellow mana manifests in the presence of matter in gaseous form, especially where it's windy. On Earth, the guardian of the yellow mana temple is the dragon goddess Dreflasa. Yellow mana is used in many weather-affecting spells and fire magic.

Black Mana

Black mana manifests in the presence of gravitational fields or in cold and dark places. On Earth, the guardian of the black mana temple is the dragon god Sool. Black mana is very rare in nature since most other colors are more likely to manifest, thus it can only be found in empty space in the shadows of moons and planets. Black mana is mostly used in cold and gravity spells, and spells that induce undeath.

Brown Mana

Brown mana manifests in the presence of spacetime. On Earth, the guardian of the brown mana temple is the dragon god Comgarosa. Brown mana has never been found naturally since even though spacetime is ubiquitous, mana will manifest into any other color over brown mana first. It is hypothesized to manifest in intergalactic voids where too little of anything else exists to compete, but it has never been observed. Brown mana is thus quite expensive, and generally can only be found near mana stations that specialize in its production or in crystal form. Brown mana is used mostly for spells that alter space and time, including portals, making it less commonly needed by most mages but very high demand for the Wayfarers' Guild.

Indigo Mana

As stated, indigo mana is mana in its raw state and doesn't manifest in reality. Still, there is a mana temple dedicated to indigo mana on Earth, and it's guardian is the dragon goddess Alasdrexa. Since it can be used in place of any other color, it is used in spells that do not have an obvious color requirement. Most commonly, indigo mana is mined in certain parts of the astral plane as crystals, called astralite. Astralite is used to reinforce weapons and armor, or other items that need to be amplified beyond their material's physical or chemical capabilities. Since even on the astral plane astralite is rare, and mining it is extremely difficult, astralite is believed to be the most expensive material in the universe, and is worth far more than rare metals like gold and platinum.

Type

Metaphysical, Astral