Tatsu/Tahotsu/Dak

Long body going to a maximum of 7 kilometres,various blue coloured scales, Short white manes with hair like thin Lionfish tenticles, Several horns, Often has a long moustache the same colour as their scales, several sharp black teeth, a flexible skeletal system and an eel-like nervous system to generate large amounts of electricity. Tatsu also contains long wing-like fins for high-level propulsion where their arms and legs would be, along with gills and lungs to breathe on land and water. The exceptions being Oryu and Seiryu who were born from space and were thus adapted to wander planets. They also produce a sticky substance on their scales at an adult age when their electricity become stronger, to help contain their electricity and prevent it from shocking itself, which is why when they are on land they leave trails of slime in the ocean, which the fish feed of, thus making it a great hunting tool.

The Tatsu will spread large orange eggs within a kelp forest, which, when hatched, are the size of a great white shark.

The Tatsu starts very eel-like without their legs, hair or scales, and at the size of a great white shark with large 1.5-metre fins. Some didn't use to make it to their next stage because they were mistaken for actual eels, but during the isolation period, they would soon grow hind fins as their bodies become longer and their hair starts to grow. As their bodies grow more, their two main, big horns begin to grow, which is where they can finally control their electricity in large bursts which only conduct through a 1 metre radius, compared to smaller bursts in their child years. The Female Tatsu have more horns on their heads and bigger bodies, with two main big ones from their forehead and horns on the side which get smaller as they go down in a curved shape. Thus, despite a male emperor, the system is mainly Matriarcal rather than Patriarcal.

The Tatsu mainly live within the oceans and seas, though some smaller Tatsu live within Nomad's Sea, a large lake. The exceptions were the 2 great dragon beasts, Oryu and Seiryu, though they did not adapt to the ocean and were technically classified aliens whose original forms were Tatsu like, but with legs and wind manipulation.

The Tatsu are omnivorous and thus feed on kelp, but also species of salmon, tuna, krill, and even sharks as their meal. Occasionally a very skilled Tatsu will end up killing a water bird. The Tatsu is very self-reliant, and every age will learn to hunt for their own plentiful fish.

Tatsu starts out as Koi fish along the Kashigyoro (River of Fish Dragon), they cross every Island and go up to a waterfall. Though they do not know the reward they climb the river and turn into Tatsu. Nowadays this process is rare, but now Tatsu lay eggs to make descendants.

Whilst Ryujin or Dakisi is the primary emperor of the society, the so-called pack leaders are almost always females known as Akdwokjang due to their more giant horns and build and better electricity production. A Male, however, could get the same rank as a female if they were struck by lightning, as their slime becomes thicker and their horns become bigger as a split second adaptation.

The Slime often left behind by the Tatsu makes great fishing bait when solidified and made into a ball or used to coat the cloth bait. When it is hardened for a day without water, it becomes a clay-like substance, but when it is is hardened for ten days, it becomes more crystalline and hard, which then can be crushed up into a clear salt and added to Kitusu to increase its effects, but was only discovered after the Peking War when a chef wanted to experiment with the Slime's properties.

At least one is found in each body of water.

While the Tatsu can see perfectly well in the water they adapted to, they are nearsighted on land, making land animals on water like seagulls hard to find and eat, making it a delicacy and a sign of great huntsmanship if one manages to catch it. It was theorised that the Tatsu had mistaked the Helmgar warships as large fish or birds, and thus swam up, wrapped around the ships and sunk or crushed them. The Tatsu also contain the ability of electroreception along their scales and jaw to survive deep or dark water.

The dragons contain a naming system similar to the Nomadic and Eurinid Naming traditions, where the name changed depending on the event one goes through.

Tatsu only sees beauty in how electricity is made. The Tatsu can manipulate their electricity into speech to communicate underwater and create light shows. Each time a female wishes to propose to a male, she will make a dazzling light show to impress the family's female. The most skilled in light making is an Uchukhung or 'Lightning Weaver.'

Despite the Matriarchal system, they still follow a regular hunter-gatherer civilisation where the men hunt and do physical work whilst the women farm kelp, seaweed and coral in large reeflike paddocks and write scholarly articles. Creation in this society is considered more hard work than taking from nature itself.

The Tatsu does not have clothes that one can dress up in. Instead, they adorn their backs and the top of their head with rocks tied tightly with seaweed. The stones contain coral of all species but in a unique colour. Green is used for dinner parties because it is considered the colour of kelp and seaweed. Blue is used in Coming of age parties as they are 'Going into the Ocean' to become a better creature. Red is used in Funerals to signify blood loss. Black is used to signify an important matter that must be discussed, often of something grim, because it is used to represent the deepest parts of the ocean, where no Tatsu can thrive.

Genbu had noticed that many koi fish had swum through a river where his original human form had washed his intestines that connected the The Archipelago of Seasons. At the island of Senshihechi there was a waterfall where many koi fish turned back. Genbu noticed that one fish was trying to climb up the waterfall for several hours. After this, it managed to get up and into the ocean. Genbu rewarded his courage by turning the Koi, named Ryujin, into a Tatsu. Ryujin would build a palace under the ocean and rule the seas. Ryujin would soon be bored after a few years and notice more koi in the ocean. He decided to allow all Koi who climbed the mountain to turn into dragons but didn't inform the koi as a fun challenge and a reward for the persistent, which is where the beasts get the phrase "Becoming a Tatsu," to refer to a person who persevered and were rewarded for reaching her goals. Ryujin would later help Hoori against his brother Hoderi, steal the Imperial Jewels, Give a bell to reward a man who slew a Giant Centipede, and more.

There is an entire Palace under the South China Sea home to Ryujin, God of the Oceans and was once a koi who climbed up a waterfall and was rewarded by Genbu for his Perseverance. Ryujin would live at the bottom of the sea in the Dragon Palace, only visible when a Clam opens along a rock on the Yalong Bay. This clam has become a significant tourist spot for tourists to photograph and wait in front of, but the clam only opens when it detects only a single individual in strife.   The Tatsu also appears in Wasogo and Ainu beliefs, as one was seen shooting from the ice as lightning stuck down on a K'aisi invasion force, thus making him the god of lightning. After a good meal, that specific Tatsu heard praises and would then come back up to see the cheering of Wasogo and Ainu people, revering him as a god of lightning, and soon after his appearance showed, the god of snakes and eels.   The Tatsu would become Itj or Ici in the Wasogo language, and he would quickly help bring relations between the Tatsu and the Wasogo people after the K'aisi had taken Toro. Vouching for independence, he would later get that wish when he burst into the office of the Daimyo in charge of K'aisi occupation and demanded it to him, making sure lightning would scorch his carpets, curtains and spare uniforms. As a gift, he and his Warkwur Tatsu would get special glasses so they could see the world, and a special path was charted known as the 'Takridanosh,' which can be translated as 'Lightning Path', 'Lightning River', 'Dragon Path' or 'Dragon River.'