The solar system of this world is unchanged, however the setting takes place in the far future of mankind. Having achieved interplanetary travel and limited terraforming capability, humanity has just started to reach out into the stars. Currently the only settled celestial body is Earth’s moon or what is now called ‘Luna’. As overpopulation, climate changes, and dwindling resources became a problem on Earth, humanity faced extinction. To combat this, large corporate entities called MegaCorps began to form and were focused on finding a new home away from the dying Earth. Pooling the dwindling resources and focusing heavily on space travel and terraforming these financial powerhouses put the fate of mankind on their backs and singularly focused on escaping the doomed fate of the planet. Spearheaded by efforts from Capital MegaCorp and Juxing Qiye MegaCorp they were moderately successful. Originally titled Lunar Evacuation Action Plan (L.E.A.P.) the eventual departure from Earth was kept a highly guarded secret. However as spacecraft were being constructed and resources continued to dwindle, the 8 MegaCorps involved realized they couldn’t keep things a secret forever, so the plan went public with what was called the ‘Lunar Exodus Project’, and was sold to the rest of the world as the saving miracle for mankind.
The Lunar Exodus project was never intended to save all of humanity however. It was in truth only meant for the corporations to preserve their respective interests and escape Earth. Vast amounts of money, technology, and labor went into the project and it was initially supported by governments worldwide. All of mankind was united in solving the challenges of traveling long distances in space and terraforming new worlds. A race against time before Earth was exhausted of resources completely, the Lunar Exodus Project was humanity’s finest example of what the collective efforts of all humans could achieve. However it was also mankind’s greatest tragedy. Towards the final stages of the plan, governments started doing the math, cultures began to clash, and wars started breaking out. Forced to hold out as best they could against the chaos of a dying world the MegaCorps started construction on the moon and finalized the atmospheric processors and gravity wells needed to make Luna habitable. During this time several of the project’s spacecraft were sabotaged, resources were stolen, and a whole slew of problems on Earth were delaying the progress. In response to this the MegaCorps began to form their own armies and security forces. Forcing anyone not an employee at gunpoint to vacate the corporate holdings and essentially cutting off humanity from the very project that was supposed to save them. Earth had reached almost 200 billion people by this point but there was only room enough for 1 billion people on the Exodus Ships at a time. And unbeknownst to Earth, the construction on the moon was only capable of housing 50 billion total. In a place the MegaCorps called ‘Luna City’. The MegaCorps kept this a secret until the last possible minute. They finished their terraforming efforts on the moon and loaded their Exodus Ships and departed for the moon. Taking with them their leadership, key personnel, brightest scientists and engineers, and their families on the first trip.
Because of all the infighting on Earth, the MegaCorps were only able to make two total trips. Relocating roughly 2 billion people from Earth to the moon. On the second trip the MegaCorps brought the rest of their employees and important people that could contribute towards sustaining efforts on the moon. Earth tensions reached a boiling point. The Earth governments and people were outraged at having lost total control of the Project, cultural infighting over who would travel next was to the point where hatreds threatened efforts on the moon itself. Corporate security started clashing with Earth’s armed forces trying to keep people out of the launch areas. In response to this the Moshchnyy MegaCorp made a decision that was not sanctioned by the other 7 MegaCorps. When the Exodus Ships were sent back to Earth for a fated third trip, the Moshchnyy security forces secreted nuclear bombs onto each of the ships. Then while they were on Earth loading the next round of passengers, many of whom were Earth's government leaders, they detonated them all simultaneously. Coordinated with a series of strategic orbital nuclear strikes on key Earth government nuclear facilities worldwide, in a span of a few hours, humanity saw the single most loss of life in human history. Hundreds of billions died in nuclear holocaust and those that didn’t, eventually died in the resulting nuclear winter. This coupled with the loss of all of the Exodus ships marked the end of the Lunar Exodus Project and sealed Luna off. What remains of Earth now is an irradiated wasteland incapable of supporting any life, and is unable to be re-terraformed for several millennia to come. Which was originally in the plan.
With humans being the dominant race in Luna City many of the languages and cultures throughout the world are parallel to real-world nations and countries. British, Spanish, French, German, Japanese, and Chinese language and cultures are referenced to help provide uniqueness to the various people and provide easier descriptive use of those motifs. All races who grow up within the various MegaCorp districts will speak the native tongue of their corporation. Essentially the world is designed to be a sandbox of cyberpunk human life, and technological sub species such as AI, robots, or synthetic humans. By keeping them closer to the usual sci-fi stereotypes, it allows for easy understanding of each of the races and cultures, without having to get heavy into the lore. To ensure all races and cultures can easily communicate with each other, for the purposes of language in the story, all races can speak “Common” (English) in addition to their native language. However when they speak in "Common" it will have a distinct accent reflective of their native language.
Luna City is mankind’s largest city ever built and their new home. A high tech marvel with roughly 5 billion people living there. It covers roughly 1/3 of the surface of the moon. Around 1,200km across it is a massive urban sprawl. Picture a cyberpunk dystopia with towering skyscrapers, rain-soaked neon, and perpetual fog. The atmospheric processors that make the moon sustainable to life are not world altering type facilities. They simply make local planetary conditions habitable. Because of this, the city and surrounding areas take on a lot of the gray and blackness of the Lunar surface. The sky is naturally light gray or white colored, making everything seem cloudy during the day. At night Earth can be seen in the sky, but instead of the blue color it used to be, it instead looks more like Venus and is now yellowish-brown colored. A constant reminder of the mistakes of the past. The moon itself is mostly fully terraformed on the other 2/3rds of the surface. Trees growing in the unsettled mountainous areas and plains have soot colored bark and dark forest green leaves. The grass naturally grows white, and must be genetically altered to take on any green color in city landscapes. The oceans and lakes are filled with clear pure water but look like black glossy voids. There are no wild animals apart from stray dogs and cats brought from earth and abandoned. Rats, pigeons, and cockroaches also managed to hitch a ride on the Exodus ships, so those exist in this world as well. Livestock have all been replaced by lab grown meats that negated the need to bring any to the moon. Unlike with Earth, mankind learned from their mistakes and do not use up the resources that are on the moon, treating it like a protected natural preserve. Instead they send out robotic mining and resource ships that travel to the asteroid belt and beyond to collect resources like water, metals, silicones, gasses, and soils. These trips can take years and subject the robotic resource gathers to hostile environments, so a vast majority of them are automated and controlled remotely.
A feat of advanced engineering and construction the megabuilding is a testament to futuristic design. Each taking up roughly 40km by 40km blocks of space, these towering behemoths can extend up to 60km into the sky. These colossal structures are self-contained cities of their own and can house roughly 850,000 residents each. Everything from shopping malls, residential housing, commercial businesses, hospitals, movie theaters, schools, corporate security police stations, restaurants, and everything in between are all contained inside. The higher levels tend to be reserved for the wealthier residents and there are scores of maintainers and corporate service workers that keep the building operational. It is not uncommon for people to live their entire lives inside these buildings and never set foot outside. Travel around the building is a mix of elevators, monorails, escalators, and walkway bridges. Lighting depends entirely on what floor you are on, the maintenance upkeep at the time, and how much money is spent on a building sector. Some areas actually mirror a 24 hour day and night cycle, while others do not. Every entry and exit to the megabuilding, to include arial landing pads are heavily guarded by the corporation that owns the building. The people living inside subject to whatever laws and customs that corporation has in place as the entire space is considered private property for that corporation.