Airlandian

Airlandians are a sapient humanoid species native to Airlandia, a once Earth-like planet whose atmosphere was rendered inhospitable after a comet tore away most of the oxygen in its atmosphere and replaced it with toxic alien gases.

Biology
Airlandians are externally identical to Humans, and require oxygen to breathe, able to be poisoned by the alien gases brought by the comet.

Culture and society
Airlandians, prior to the comet cataclysm, were ruled by a monarchy and protected by a military force known as the Air Guard. However, after the cataclysm, the Air Guard were turned into the Tyrants of Wind, with the monarchy converted into a military dictatorship under a new emperor. Under the new dictatorship, ruled from Central Airlandia City, the Tyrants of Wind were organized into the Air Lancers, an air force division, and the Enforcers, who wore purple and grey armor and patrolled the streets, brutalizing and incarcerating any civilian they pleased. General Airlandian clothing and architecture, at least in some areas, bears a medieval aesthetic, and due to the effects on the atmosphere, breathable air became an incredibly valuable resource. The Tyrants of Wind are in near-complete control of the planet's air supply, rationing it in amounts too small for most to survive on and forcing small communities to surrender their reserves, although certain holidays, such as market days, prompt Airlandian noblemen to fill entire cities with breathable air to allow the general populace to breathe freely.

While air is the most valuable commodity in Airlandian society, Airlandians also utilize a currency referred to as credits. There are Airlandian professions known as "air farmers" and "air miners," with the former presumably gathering what oxygen remains in the atmosphere into air tanks, while the latter presumably mines ice that can be used to get oxygen. There is also a type of Airlandian food known as "Air Burgers," but it is unknown if these somehow contain air within them or if it is just a brand name. Large Airlandian cities utilize a public transit system known as Sky Glider monorails, and are covered in surveillance systems, including two-way televisions known as vapor lenses, with civilians arrested for merely being suspected of being dissidents. As a part of their control system, the government constantly feeds the populace with propaganda, portraying the emperor and the Tyrants of Wind as heroes, while the Air Raiders, a faction of dissidents that worked to give free air to the populace, are portrayed as terrorists.

Technology
Airlandian technology is more advanced than that of Humans, although they are unable to achieve space travel due to the fierce turbulence of Airlandia's upper atmosphere. Airlandian cities are filled with advanced technology, from high-speed monorails to sophisticated surveillance systems, and breathable air is created in refineries and circulated throughout the cities to households and individuals. For travel in places without breathable air, Airlandians utilize air tanks attached to respirators, whether these respirators be simple masks or parts of armor. Airlandian Enforcer armor, equipped with a 2 day air supply, are durable enough to withstand indirect concussive blasts, are thermo-insulated, and carry a built-in computer system.