Zet

Primeverse
The Zet are a race originating from Legend of the Ultimate Sword's Primeverse, on planet Valore. They are a sub-species of the Valore race, with only six living specimens - six fraternal twins; four male and two female. They are the result of genetic engineering performed by Valore's visionary biotech scientist Anima on herself while pregnant. As children of Anima and Taliro both, they are subject to Zan's subconsious influence, but gifted with vast physical and mental abilities as well. They stand as demigods among their Valore predecessors, and are revered as the destiny-manifest rulers of their world. Even in the future, among the high-tech denizens of the galaxy, the Zet are considered awe-inspiring and fearfully powerful. A Zet wielding an Ultimate Sword cannot be withstood by any other single individual in all of Sinon.This appears to be the very purpose for which Anima creates them.

Unfortunately, the Primeverse Zet are never seen in narrative due to the events of the Mazzaroth Disaster. After it occurs, there are three Verses which contain different versions of the Zet. However, Drake reveals in narrative that the Alphaverse Zet are nearly identical to their Primeverse counterparts, so the description of the Zet in the Alphaverse section suffices for both. Once the Zanhoshi Reunion is complete and Omegaverse is created, the Zet become Omega-Class Entities, also known as the Omega Zet or Omegaverse Zet. At this point they become incorporeal, so their traits are only visible when manifested by their Avatars.

Alphaverse
(Identical to Primeverse Zet)

(also known as Alphazet)

General
Alphaverse Zet all have white hair and very pale skin, though each has a different eye color. The Zet of each Verse share the same skin and eye colors as their counterparts. These features become luminescent under certain conditions (e.g. eyes lighting up when excited, body glowing when readying for combat).

A Zet grows hair only on the scalp and eyebrows, though Thanatos sometimes sports facial hair. In addition, interspersed with the hair is a type of fur which grows to a specific length, in a specific style, usually in defiance of the hair. Zetoshin manages this by cutting his hair short and keeping his long fur in a ponytail (at least before cutting it all short), while Thanatos lets both grow out. The other Zet have naturally shorter fur, though its stiffness and thickness lend a wild, gravity-defying look to their hairstyles.

The Zet are extremely strong and durable, with most of their body being made up of porous, metallic crystal lattices. Their composition differs greatly from one individual to the other, with the diminuitive Zetoshin having the greatest density (400 lbs at 4 feet tall!). This does not seem to affect their strength and durability - Thanatos' body is no more dense than a human's, yet he and Zetoshin are evenly matched.

Furnace
While the Zet possess a pair of lung-like sacs, their alveoli are vestigal, and the sacs primarily serve as back-and-forth bellows attached to a third organ. This organ, called the "Furnace", is located between and behind the bellows-sacs, to the right of the heart. It processes inhaled gases before combining them with metal oxides and other ingested fuel to generate heat through chemical reaction. If the Zet inhales water, small amounts can be electrolyzed into combustible components, though other liquids prove more difficult. However, large amounts of any incombustible liquid can interfere with Furnace operation, and must be diverted elsewhere by the body. Most of the heat generated in the Furnace is used to boil waste fluids into dry vapor, rendering them relatively harmless until they can be ejected. A Zet's insides must be kept free of such substances so that they will not short-circuit the nervous system. Because all but a Zet's steamgill sacs are porous, prolonged contact with (or even momentary immersion in) water can prove as hazardous as inhaling it.

Steamgills
Steamgills are two sets of three diagonal slits on either side of a Zet's lumbar region, which allow them to vent excess liquid and gases from their bodies. The waste is collected behind the gills and superheated under extreme pressure by the Zet's natural energy flow and resilient cavities. At opportune moments, a Zet may open the gills, and a gout of dry steam is expelled. The temperature and pressure of these expulsions can rival that of a nuclear reactor coolant breach during meltdown, but they are mercifully small in volume and (usually) nonradioactive.

4D Dynamo
This organ is designed with the express purpose of transforming, storing, and releasing Tachyon Waves of the sort produced by Contact with an Omega-Class Entity or Zanhoshi. It allows the Zet body to handle far more tachyon energy than any other race is capable of handling, without self-destructing. Only part of the Dynamo exists within normal spacetime, with the bulk of it extending into a higher dimension, where it can make direct contact with the probability-axis currents produced during Omega Mode. Even after the tachyon wave subsides, the Dynamo can contain enough energy to extend Omega Mode activity to twice its normal duration.

Wielding A Zanhoshi
(Fucking run.)

When a Zet takes hold of a Zanhoshi, its massive energy surge is absorbed by the 4D Dynamo, preventing the Zet's death. By safely controlling the influx of the Zanhoshi's power with the Dynamo, the Zet gains all the powers associated with Omega Mode for as long as they hold the sword. Unfortunately, the Zet are subject to Zan's influence - if they access Omega Mode powers without making Contact with their actual Omega, they are vulnerable to direct control by Zan. At the original activation of Zanhoshi Prime, Zan takes direct control over one of the Zet, and it takes the combined efforts of the other five just to tear the sword from their grip. However, once a Zet has made Contact and reached Omega Mode at least once (such as during the Mazzaroth Disaster), taking hold of a Zanhoshi only slightly increases Zan's influence.

Negaverse
(also known as Negazet)

General
The Negaverse Zet all have black hair, and in some cases strongly resemble their Alphaverse counterparts. However, their biology is significantly different, with no Furnace, Steamgills, or 4D Dynamo present. Instead, by an unknown means intrinsic to the molecular structure of their genes, the Negaverse Zet body can determine or alter the outcome of collapsing quantum superpositions which occur within it. Because of this, their bodies are immune to the forces of entropy, and can reverse it at will to produce extremely unlikely outcomes. This ability is identical in effect to Alphaverse's Trintian magic, but its operation is purely instinctive to the Zet; no training is required to use it as they see fit.

Tuning
Because of the above-mentioned ability, when in the presence of foreign laws of physics, the Zet will effortlessly adapt to them, maintaining quantum stability and power generation. This makes it possible for the Negaverse Zet to migrate to Alphaverse without suffering any side-effects from vacuum decay.

Wielding A Zanhoshi
Negaverse Zet are immune to the negative side-effects of contact with a Zanhoshi. However, because the Zanhoshi's power is infinite potential energy phenomenon, a Zet may still access its full power.

Sigmaverse
(also known as Sigmazet)

General
Because they remain in Sigmaverse until the Zanhoshi Reunion, the true nature, powers, and appearances of the Sigmaverse Zet are never described in narrative. Here are all known facts:
 * They have a Mazzaroth that isn't powered by a Zanhoshi, which they use to locate Alphaverse.
 * They discover first Alphaverse, then the tachyonic probability-waves of Omega Mode phenomena occuring there.
 * They use the Mazzaroth to bridge their timeline's probability axis across Alphaverse's tachyon phenomena, giving them the ability to possess Avatars in Alphaverse with the same powers as their Omega counterparts.
 * All this is done to manipulate the outcome of Zanhoshi Fusions happening in Alphaverse, such that Sigmaverse's identity will prevail over all others during the final Reunion.
 * In Sigmaverse, Zetomaru is responsible for the creation of Zanhoshi Prime, which in their Verse is known as World of Blades.

Sigma Avatars
Due to the difference in quantum vacuum states between Alphaverse and Sigmaverse, the energy generated by Sigmaverse Avatars grants them magical powers even when not in Omega Mode/State.

Trivia

 * Every "version" of Mezzo is actually the same person. No explanation is given in narrative.
 * Zet is short for "Zetto", the Japanese way of pronouncing the letter Z.
 * The name is also inspired by the Hebrew word sedeq, which means "righteousness". Even Zetictech Games is named for it (Zetic = Sedeq).