Destruction Factor

**Destruction Factor** or **Extinction Factor**「滅亡因子, *Metsubō Inshi*?」 is a term used by magicians to describe powerful mysterious beings that regularly appear on Earth with the purpose of destroying all life. They are neutralized by a special magician organization, <Knight Order>.

## Information

### Nature

The nature of the Destruction Factors is unknown. Throughout the history of their appearance on the Earth, their striking variety has been noted: in particular, Kuroe noted this fact as follows: "*The fruit of wisdom, capable of creating weapons that crush the stars; anomalies of spiritual lines that cause every conceivable cataclysm to occur simultaneously; invasions of golden locusts that devour everything in their path; the great deadly plague, the calling card of the angels of death; messengers from the future, crossing time to change history; giants shrouded in hellfire that drown everything in fire with their very presence*".

At the time of events of the first volume, there were 15,165 appearances of Destruction Factors in the entire history of the world. According to observations, they appear on the planet on average once every 300 hours to destroy all life in range.

#### Ranking

Each appeared factor gets a code name, a number, and a rank, depending on the expected damage. The number of the factor is directly related to its rank and threat to the world, with a lower number corresponding to a greater danger. They are subdivided into Catastrophe, War, Collapse and Fantasy ranks, and magicians of the corresponding classes deal with their elimination.

### Countermeasure

For each Destruction that appears, there is a time limit in which it can be neutralized. This time period is conventionally called a «Reversible Annihilation». If the neutralization is successful, all the death and destruction will be reversed to normal, as if nothing had happened.

However, if a magician dies during a battle with the Destruction Factor, reversible annihilation will not be able to resurrect them, unlike normal humans.

## List of Destruction Factors

### No. 206: «Dragon»

As the name implies, it is a huge dragon (but much smaller than Fafnir). They have tough skin, sharp claws on its paws, wings and a long horn on its head. According to Kuroe, a single Dragon is strong enough to burn down Japan in a few days. They are also resistant to the weak attacks of magicians. In addition to physical attacks, they are capable of fire breathing.

### No. 302: «Kraken»

A relatively common Destruction Factor out at sea, Kraken is an enormous squid. Two Kraken boasting record-breaking sizes attacked Hollow Ark in volume 3. The first Kraken was fend off by the Azurs while the second was eliminating through Mushiki using Saika's Fourth Manifestation.

### No. 329: «Slime»

A jelly-like substance that can digest everything in its path. Individually, each of the factors is not particularly strong, but in a group they pose a real threat.

### No. 414: «Ghost» (Wraith)

Has the appearance of humanoid shadows. Apparently, they appear and attack as a group.

### No. 511: «Leprechaun»

At the moment, nothing is known, except for the number and name.

## Mythologia

Mythologia are 12 Destruction Factors with the highest ranking (noted ordinally, from 1 to 12), and boast having mythical rank. They are extremely powerful Destruction factors, and only Saika Kuozaki could defeat them in the past. According to Silber, if Future Saika's threat level is properly gauged, she would be included in their ranks and there would be 13 Destruction Factors.

### No. 004: «Leviathan»

Leviathan is a enormous sea monster known as the ruler of the oceans. 200 years ago, Saika needed to team up with Ao Fuyajou in order to slay the beast. However, prior to its demise, it marked Ao with its cursed spell, causing the Magician never-ending pain and forcing her to swap bodies every 10 years for the next two centuries.

In the climax of Volume 3, Leviathan is brought back in an incomplete state, which is described as more skeletal than flesh. Despite not having access to its full powers, its resurrection was still enough to flood the entire world in an instant. In the end, Mushiki nullified the lingering curse on Ao's soul, then Leviathan is slayed once again thanks to the power of Ruri's Fourth Manifestation.

### No. 008: «Ouroboros»

Ouroboros is described as a gigantic serpent eating its own tail. Its special ability, immortality, is classified as a threat for tampering with the balance cycle of life and death.

It is the only Destruction Factor that cannot be killed, instead being split into 24 pieces and sealed in separate places, with guards from various affiliations, including Void Garden and Shadow Tower, watching over the seals.

Currently, its head and heart parts were fused with Kurara Tokishima, who gains its abilities and incorporated them with her own.

### No. 010: «Fortuna»

A material type Destruction Factor that takes the form of a ring. The ring is capable of blessing the user with good fortune and can grant any wish. However, the wishes come at the expense of consuming portions of reality, which is marked by locations in the world disappearing as more wishes are granted. Due to assimilating Sara Svarner 100 years ago, its authority was passed onto her next life.

### «Cupid»

Number classification is currently unknown.

## Trivia

* The Destruction Factors are similar to the *Spirits* from Kōshi Tachibana and Tsunako's previous series, ***Date A Live***, with both being described as "disasters that destroy the world" and characterized by a number.
	+ The difference is that, whereas the Spirits are intelligent beings who were later revealed to actually be ordinary humans turned into Spirits, Destruction Factors are genuinely just mindless monsters.