A rare currency that can be used to buy in-game items. Can be exchanged from Ultracubes.
Hypercubes are the only expendable minerals that can help humans withstand "the Calamity". In the Nightfall era, after the Perishing Star descended, Hypercubes became a vital resource to sustain human survival.//
Overview
Hypercubes are extremely valuable as a source of energy and for their anti-Mania properties. The DisCity owes its relative prosperity and stability to the fact that it is the sole manufacturer and exporter of Hypercubes. In order to preserve this position in the new world order, the trade of Hypercubes to OutLand is strictly regulated and it is nigh impossible for private companies to obtain transportation or other rights to Hypercubes. As of N.F. 112, Hypercube transport has been monopolized by Nirvana Transport. Information on them is so strongly protected that even the 9th Agency requires permission from Paradeisos to look into Nirvana's files.
Hypercubes were first discovered by the scientist Keylan in the DisSea, where the Perishing Star meteor made first impact on the earth. All communication was cut off from the expedition team after they entered the death zone in N.F. 23, and Dr. Keylan is the sole survivor who brought the Hypercube out into the world. The DisSea is the only known location where Hypercubes can be found natively.
Before the DisSea Explosion, Hypercubes were mined from the DisSea and processed in the West District. The DisSea Explosion resulted in widespread contamination, ruining the mines within and causing a sharp fall in Hypercube production, leading to the decline of the West District's mining industry. In the modern day, Hypercubes are hard enough to come by that even the FAC must ration them and scavenge them from their fallen soldiers (5-9). Still, many make their livings in Hypercube mines in Syndicate, despite the high risk carried by those jobs.
Hypercube veins also contain the Ultracube, an even rarer and more enigmatic crystal. Some believe the Ultracube to be the source of Hypercubes.
When processed, Hypercubes often come in hyperpyramid form.
Hypercube Production
Hypercubes begin existence as a substance known as Hypercube Monomers, which slowly form within Black Rings. The Ring Research Institute deduces that this phenomenon is akin to the precipitation process of a solute in a super-saturated solution. This process can continue to occur on the site of a Black Ring even after the Ring itself is destroyed, as seen when they begin to precipitate in Keylan Square nearly 5 months after the end of BR-004.
Despite the usage of terms like "mining" and references to Hypercube "veins", the actual process of producing them does not seem to involve any of the usual features of conventional mining. The M-31 Hypercube "mine" in the Inner Bay is a ring-shaped structure that dams the contaminated waters of DisSea to form a hollow tiered cylinder that descends below water-/ground-level. Each tier ranges between a few dozen and a hundred meters high, and bottoms out in a platform a dozen meters wide. Contaminated liquids are allowed to trickle down the walls of the mine, to accumulate in "precipitation pools" in each platform where Hypercubes will form. It is said that the mine's M-value must be kept "relatively low", but it is not clear why this is necessary or how it is accomplished if most mines exist inside of an active Black Ring's contamination field.
Early in DisSea's history, robotics technology was not yet advanced enough to penetrate the Mania fields in DisSea, requiring technicians to manually operate mechs for mine digging and ore excavation. This changed in N.F. 104, when automated mining technology became common.
Uses
The Framework Against Catastrophe is equipped with a variety of Hypercube-powered technologies, including anti-Mania bullets effective against Corruptors and protective fields that prevent Mania contamination. These fields can be projected from enormous, portable towers which are used to contain and clean up major Mania outbreaks, as well as small-size personal blockers. The standard personal blocker consumes 1 unit of Hypercube to create a field that lasts ten hours, although agitated emotional states can deplete it faster. However, even with this blocker, in a highly polluted area the carrier's M-Value will continue to rise slowly. Even then, it will greatly alleviate the holder's mental strain. (5-7)
One of DisCity's methods of combating Mania crises is with Blue Rain, a Hypercube-derived process used to cleanse contamination across large georgraphic areas within the city. Blue Rain is corrosive to physical contaminants and damaging to Mania creatures like Corruptors. Exposure to Blue Rain also causes painful burns to Sinners, although it does not seem to be life-threatening or to have much, if any, effect on the usage of their abilities. The frequency with which DisCity's authorities use Blue Rain varies. Prior to the many crises of N.F. 113, Blue Rain seems to have been a sparsely-used tool mostly employed to clean up the aftermath of major Mania events, such as the two-week Blue Rain purification period that followed the brief appearance of BR-004. During renewed lifespan of BR-002, from April to November of N.F. 113, Blue Rain was used frequently across the entire city to combat the contamination radiating from the Black Ring and to support FAC forces in their many battles. By early N.F. 114, Blue Rain was used (at least over Syndicate) once per month (Ditty Nightsong KLR-303).
There are also many civilian uses of Hypercubes throughout DisCity. Pacassi's interrogation reveals that Hypercubes can also be used to power devices, and she uses one to repair Mayek's nuclear power plant. The Belphegor Art Museum in Eastside has Hypercube mixed into its door, suggesting that they see significant use in construction as well.
Expenditure of Hypercubes also seems to be required in order to fuel uses of the Rules, although the exact relationship between them is not yet clear.
Speculation
The origin of hypercubes is mysterious and there are hints scattered throughout the game that their power is not as benevolent as it appears. The flavor text of Providence implies a sinister origin, which goes unquestioned by the people of DisCity because of their reliance on the Hypercube for their survival and prosperity. Likewise, the flavor text of Blue Rain raises questions about the nature of this procedure, seemingly tying it to the great existence that the Underground serves.
Keylan, the discoverer of Hypercubes, is described as "delving into despair to bring back hope." Given that Hypercubes were originally mined from DisSea, it is possible that this refers to his entering the original Black Ring that appeared during Nightfall and that Hypercubes first arrived on earth within the Perishing Star. Given this, and despite the accretion process through which Hypercubes are produced, there are numerous suggestions that Hypercubes are some sort of organic substance. The in-game description of the Ultracube, which has patterns that "flow and ebb like living, growing organisms". It could also be evidenced by the "Sanity Crystal" which is collected from the Outdoor Activity Area in the MBCC when Sinners are calm and relaxed (Hypercubes in the MBCC's Secret Chamber are produced through a combination of sanity crystals and fear crystals). Given that Sinners are known to grow Mania crystals inside their bodies, it is likely that these sanity crystals (and all the other forms of crystals collected in the MBCC) are also extracted from the Sinners -- furthermore, their connection to calm emotions and their near-identical appearance to Hypercubes strongly suggest a common biological origin. Finally, the description of the Dark Area of the Broken Frontline refers to the Hyperbeast enemy as "the beast with Hypercube on its back." All this taken together suggests that Hypercubes might somehow originating from the same "great existence" that they are used to fight against, as they have such power over Mania and the Mania-based entities that also appeared as a result of the same calamity that created them.