Aku

"Welcome to the world of deep waters, the waterworld of the Trimeka System, one of the many colonies of Thetis and the twin of Meksis, it's large moon. This planet is known for it's fantastic products: It's algae and fish exported all over the empire. Most notably, Aku is known for being one of the few places where humans freely inhabited and conquered successfully the underwater world. Free spirited people, adventurous and excellent navigators." - Senator, Maes PrimAku is a planet located in the Trimeka System, in the Lewis Galaxy and Herschel Space. It is under the Empire of Mankind. The planet is a complete oceanic world. It is believed that the planet had large icecaps frozen in the poles at some point in it's past, but it's ice melted, covering the already back then, scarsed lands of the planet.
Due to the ties the planet has with it's large moon, Meksis, the planet has massive tides and volcanic activity. Most of this activity takes place underwater and the tides allow for some land to emerge, like the phantom islands of Irenu. This world is a center of the algae farming and obviously fishing.
Most of the world has tremendously deep oceanic floors, up to 15 000 000 km2 deep or more. This had made the planet have it's distinctive dark blue color. Nevertheless, some regions get completely covered and uncovered with the tides. Only 3 tiny archipelagos and a couple territories that come and go with the tides exist in the planet. This means that the population is concentrated either on those archipelagos or lies over the surfaice or under it.
==Geography==
The geography of consist of several permanent archipelagos: The Tielli Archipelago, the Usarlen Archipelago and the Arbakera Archipelago. This three scattered group of islands are the tips of mountains or old volcanic islands formed during the old stages of the planet.
===Archipelagos===
*Tielli Archipelago
A long time dormant archipelago, the vlcanic activity that formed the islands long ceased to exist. Some say it's the oldest formation of visible islands in the entire planet, and has the capital of the planet over them. It is a very nice place to live. The city of Kindal, the name of the capital extends itself over the island of Tonsi and over the nearby bay.
*Ursalen Archipelago
It concentrates a large amount of volcanic activity even to this day, which is contributing to some extend to the islands becoming bigger. Most of the volcanoes here are on the islands themselves, which has made some of the islands extremely dangerous for habitation. Nevertheless some of the islands are still feasable for habitation and thus, large cities exists here.
*Arbakera Archipelago
The islands are rapidly expanding but most of the volcanic activity is happening under the surface. This archipelago holds the second largest city, the city of Emostal. It has an expanding industry and economy.
===Surface and Underwater Complexes===
There are several cities and domes that exist over the planet in it's large oceans, very much in the same fashion as other water worlds like Ishai or Kataria. This complexes might hold billions of people and are definitely centers of research, agriculture or commerce. Other use the heat of the volcanic activity underwater to produce massive quantities of energy to be distributed all over the planet.
====Underwater cities====
*Unerwater city of Luminai
This city is mostly used in for the production of energy an manufacturing. It also is used to mine minerals from the vast oceanic floor. It's located near the Jurdeniri oceanic mountain range, use to mine extensive amounts of minerals and the Hissu Cliffs, a large abrupt break on the oceanic floor that plunges thousands of  meters. It is from here that energy anf heat scapes from the underwater breach. This is harvested by energy farmers, as they are called it and then exported to other cities. It's total population is 3 billion.
*Underwater city of Atalona
Strangely enough, this city is among the largest underwater complexes. It is located near the shallow waters of the Mertatu Archipelago, it is basically base itself in research, high-tech, finance, services, agriculture, food production and tourism. The city has a burstling entertaining life as well. The city is beautifully decorated and is known as well to produce luxury items for the whole planet. Rare specialities of the underwater world. Some of the pearls of Aku are really appreciated in the Empire and one of the main comodities exported. The total population of the city is 4 billion.
*Underwater city of Drisdal
The largest of all the underwater cities, it holds extensive algae farms and fisheries. Located nearby the vanishing Braglus Island, it is a center for commerce, underwater shiprepairement, research and services. Most of it's industry is related to pharmaceutical companies and others. The city is burstling and growing and has nice standars of living for it's citizens. Some wealthy individuals in Aku live this city. Mining is also an important activity, although most of this is done to extract rare minerals. The total population of the city is 5 billion.
*Underwater city of Kolemira
This city, is basing itself on a hanging cliff, on the Naulki Breach, which is leads to the Letarni Plains, a vast plain that covers 3% of the oceanic floor and is more than 10 000 meters deep and extends over millions of kilometers. The Kolemira city is not only a military base but a center of mining, energy production, research and most importantly construction of all sort of underwater materials. It's nicknamed the Factory of the Underworld by many not only in Aku but the system. They are also famous for their architets and engineers. It has a total population of 3 billion.
====Floating cities====
*Floating city of Hansala
This city has been floating over the seas of Aku since the very beginnings of the colonization of the planet. It's structure is completely renovated but it's size is massive. This city floats on the currents and trades with most of the other cities in the archipelagos or the underwater ones. Part of the economy lies in fishing but most notably it produces goods and services and is in charge of exchaning goods and comodities. They produce high rise amount of energy, high-tech, metal appliances and others.  It's famously known for it's entertainment content and the broadcasting and News center of the planet.
*Floating city of Gurgalo
This city wonders the oceans in search of rich mineral deposits to mine. The city underwater has a large machinery complex that allows to process minerals from about 120 000 meters in depth. More than that is usually carried out by robots. For that, the city had to manufacture the robots, making it the most valuable asset of the city for exporting. The city also has a burstling insurance companies, services and industial manufacturing of high value.  
*Floating city of Karemina
Mostly known as the basquet of the floating cities, this city follows the currents to harvest the so much desired krill and to herd their livestock. Many animas live in the pools of Karemina and constant movement is needed to keep the stock alife. At the same time, cosmetics, services, textiles and services are produced in the city. Harvesting the algae on the oceanic floor and ocasional mining also form part of the city life.
*Floating city of Persanos
Persanos is a city mostly famous by it's entertainment, but the city is not only that, it is a place of research and military. The city patrols the oceans in search of runaways or pirates and also and most importantly in biological, sysmic and oceanic research. Many cientists live in the city and work here fulltime. Other products the city offers are high-tech, medical appliances and pharmaceutical processed products.
===Phantom Islands===
There are as well several islands that are discovered when the tides get low: The archipelago of Irenu, The Dacna Archipelago and the Mertatu Archipelago, as well as the Yubepa Island the Braglus Island. Most have signs of early surface-like lifeforms, meaning they were at some point outside of the water completely, including the period of tides. Concerning the fact that Aku has no icecaps, some theories proved that in fact, most of the ice melted away from the planet at some point, submerging many of the island previously inhabited. This island currently are base for many lifeforms, and low seas that a very diverse biology.
*Irenu Archipelago
A set of islands, frequented by many species due to it's rich soils. It serves as a resting place for the Almiris Birds, who pass most of the high tides flying and fishing, and then during low tide, resting in the islands of the archipelago. When the reproducing season begins, they create their nests on the closest land. That is the Arbakera Archipelago which still lies 15 000km away.
*Dacna Archipelago
They formed the sumits of the Nulska Peaks. It has a large fauna and flora around them and is the center of the mining activities carried on by many either underwater or floating cities. Not much more is of interest other than the top of the peaks show out in the surface when the tides are low. It is home to the Kurula, a large predator that preys on the Nadimani, a large innocent creature that lives in herds and frequently eats out of this islands.
*Mertatu Archipelago
A shallow archipelago of submerged island, it is covered by a low sea. It has a large fauna and flora around them and is known for it. Floating cities tend to avoid passing by the archipelago, to not be stuck in the submerged peaks of the islands. When the tides move away, the islands are completely unveiled.
*Yubepa Island
It's an island that emerges from time to time. According to many it is the home to many good fishing grounds and some species of large animals are often seen closeby. Nevertheless, the islands are over a volcanic region which is still on high activity under it. Although not enough yet to form islands that are able to reach the surface for now. A tiny city called Lakrin is on this island and emerges when the tide goes down.
The city of Lakrin is a recent city that has emerged to harvest the energy and minerals of the volcanic activity. This rich sources is latter processed to make fertilizes for the other cities which harvest big amounts of Algae. This city has seen an exponential growth from 300 million to 1 billion is just over three millennia.
*Braglus Island
This islands os knwon to be one of the most filled with fauna. Many species live here and is a common resting place for Amiris birds. The internal volcanic activity is not dangerous nor toxic and seems to be adding kickly new levels of earth which will eventually make the island completely emerged. Braglus currently is a huge island that comes to the surface often.
==History==
The World of Aku it's tightly connected with Meksis, it's twin. It is believed that Meksis in the past gathered a Wreteren colony,thus the nomenclature of the moon. Early exploration missions into the system tend to avoid the Aku-Meksis system but increase pressure from settlers made the military forces get involved, expelling the Wreteren from the planet. This had implications, meaning that the expelled forces formed one of the Wreteren clan-tribes of the Wreteren Syndicate.
The first visit into the world of Aku was amission sent in the year 30 102 CE. During this time, the planet was explored and it's study began. However, it would take more than 150 years to settled the planet. The small war going on in Meksis to drive the Wreteren out seemed to have delayed the process.  
It wasnt until 30 282 CE, that Aku was colonized by the first settlers. The first ones arrived from Thetis. It was considered that as Aku was a water world, Thetisians would be easy to adapt to this enviroment. And they did. They soon were followed by colonist from other watery worlds and a society began to be build in the planet. First, around the islands of the planet, but soon it became clear that they would not be sufficient to hold the entire population. Thus, the first floating cities emerged, cities that would be travelling from one archipelago to the other in what would be called the triple voyage which visited the three only archipelagos inhabited.  
When the surface of the ocean was explored and the settlers began exploring the depths of the oceans, the need for more resources pushed them to live underwater in what would be called underwater cities. This cities quickly flourished and many colonist moved in, making this huge domes explote in life. The technology to substain life kept improving and the cities kept growing. During the wars, this cities became untouchable, as they could be easily be held by the settlers. The Tarkonau Order however tried to visit the planet and launch an assault underwater, with mild success.  
==Fauna and Flora==
*Almiris birds
This birds with a hard body are able to endure large storms that frequently hit the surface of Aku. During this storms, the birds are able to fly high up with their resistant wings. They spend much of the day flying and can do so very quickly. During high tides, who cover up most of the Islands, they live high up in the air and in low tide they sat in the emerged islands to rest and feed on the fish caught by up. In reproducting season they land in the permanent islands to form their nests.
They live in huge groups up to 25 to 50 individuals and use their large numbers to protect themselves from aggresion. In cities they are considered highly molestous and are one of the most prolific air creatures in Aku. The females can lay as much as 20 eggs in a next and carry them in their hard shells although only a quarter reach adulthood. Of these, only half would make it to reproductive age. This bird has predators as well, and thus the offspring, specially young, is subject to be hunted.
*Kurula
A huge predator, roaming the oceans of Aku, it is one of the most known pray. It moslty hunts the Nadimani but aslo other prey like the Almiris bird if they spend too much on the ocean surface or hunting and the Siru, as well. In rare occasions it has been seen hunting the Vangals, which are considered difficult prey for them. Specially for males which are very large for them to hunt and the calves, which are typically the only prey they can get, are well protected by the Vangal families which will defend them.
The Kurula are lowners and do hunt alone, only females carry their offspring which they take with them for over 4 years.  They can live between 50 to 60 years and have about 4 or 6 offspring in their life times. Twins arent rare in the species. They can be very fast but usually avoid the seas where Human cities are located.
*Nadimani
This large hervibores live in groups, large groups of over 100 inividuals an roam the oceans in search of algae, the so called microalgae that flow with the current. They are often seen in the oceans of Aku and are an expectacle to witness. During the large migrations, the skies are covered by dozens of Nadimani, smaller groups concentrate themselves in herds of over 2000 individuals.  
The lifespam of these animals is 20 years and usually they carry offspring for over 1 year, reproducing quite fast. Females get pregnant every single year and deliver one calve. However, about half the calves a female delivers would never reach adulthood. The group offers protection but not as much as to loose calves to predators. Most notably the Kurula.
*Siru
The siru is a low key predator, it feasts on fish, shells and the Almiris birds even. He is quite agile and a good fighter. It's beak-like mouth allows them to access hard food. Of all the animals found in the planet, the Ukorke is his favourite prey and his skin is proved agains electric signals. This means it's completely isolated from electricity and the surrounded electric fields of water around. The siru is however very shy towards humans and ofter runs away. The siru is also hunted sometimes as a delicacy in Aku. The Siru lays 20 eggs, usually in a shallow cave of the rocky areas around. Where it becomes very protective. The Siru usually mate and stay as a couple for about 4 or 5 years when they successfully raise a couple eggs of offspring. Once done this 2 times, they change couple. Otherwise they do everything together.  
*Vangals
This animal of huge size is known as the whales of Aku. Large animals with fluorecense shine in the deep oceans of Aku. Apparently the Vangals were some sort of terrestrial animal that adapted to a life in the oceans millions of years ago, when Aku had larger islands and still had icecaps. Apparently the meltic of the ice accelerated the jump of the proto-Vangals into the oceans. This animals live in small groups of 3 to 7 individuals, usually a Matriach female, her daughters and grandaughters or grandsons (Calves). Males are always on their own.  
They use their fluorescence to communicate and hunt. This animals are appreciative and have formed the emblem of the House Tarvan, on the service of House Lavey, who controls the system.
*Ukorke
This creature is very strange. It is capable of creating energy, electricity fields the Ukorke uses to hunt and fish. This creature's biggest predator is the Siru who is able to resist the electric charges of the Ukorke and to pierce it's shell to get to the soft tissue inside. This creature lives in large groups, when they are young and vulnerable. During this time, which might be the first decade of their lifes, the Ukorke mesure between 10 cm and 50 cm in lenght. They are easy prey for the Siru, so they use their numbers for protection. When they reach 1 meter they leave the groups and become solitary. If they survive 10 years, the Ukorke can reach 3 meters when they become less of a prey for the Siru. They will keep growing all their lifes until reaching sizes of 50 meters in the biggest members of the species, although the usual size is between 20 and 25 meters if adults at least 20 years of age. The older they are the bigger they get. The speciments reaching 50 meters were about 100 years and are rare. It's stimated that 90% of the Ukorke die in the first 10 years of life.  Females lay eggs in a sack and those are broken into the current. The Ukorke launch their eggs in a massive reunion all at the same time, which attracts thousands of creatures. Those eggs float in groups in the current and crack with millions of them being born at the same time. One single Ukorke can have up to 2000 eggs at a time. The shell doesnt grow firmly until they reach 1 year.  
*Tali Rays
Beautiful animals, known to life all their lifes in pairs. The female and the male are slightly different. They live out of microroganic compounds they suck from the current, like the Ukorke eggs among many others. They filter large quantities to get nourrisment. This animals who live in couples reproduce by laying eggs into the current, which in reality might end up canibalized by other Tali Rays without noticing. They are huge in length and might e yo to 10 meters from one point of their fin to the other. They are blind but do communicate through sound and sensors.  
This animals are really unharmful to humans an are rarely included in the diet of main predators although a hungry Kurala may end up eating them if needed. They live up to 20 years and reproduce every year, reaching adulthood after 2 year of age. However, about 90% of the offspring of a couple in one go never makes it into Adulthood.