This is the first world in a series for use with Dark Heresy. These worlds lie outside the Calixis Sector and may be incorporated into any other sector desired by the Game Master. Plots that link these worlds may appear in other posts in future.
Hive Saelex-3 - The third moon of the gas giant Saelex is a hive world that thrives on the riches of the gas mines orbiting Saelex; the gas is used to fuel the hive-city built on any available surface of the cast mines where the core of Saelex-3 was drilled out by the miners to create the gas mines. The other two moons are small rocks without atmosphere used as relay stations for the communications networks between the orbital mines, spaceships and the hive.
The surface of Saelex-3 is a sea of antennae, crevasses leading into interior tunnels (known to the natives as Cuniculi), solar cell domes and outward-facing docking towers (known as the Clavi Imperialis) where spaceships land. Atmosphere on Saelex-3 is sparse and tainted by pollutants that exact a toll (10 minutes x Toughness bonus before you take a Fatigue level) on those without fresh air. Rebreather refill sales are brisk (such canisters are Easy to obtain).
The Clavi Imperialis are decorated with plasteel icons praising long-dead heroes of the Empire where Saelexian mining ships pump their gas cargo in return for payment. Open flames of any kind are prohibited by law in case of gas leaks - Arbitrators, workers and tech-priests who work the Clavi are keen to extinguish fires at source. Gas leaks are not commonplace but the resulting inferno makes everyone suitably edgy and means that a loss has been made.
The interior tunnels (Cuniculi) are wide enough to navigate a guncutter or Aquila lander through (Ordinary; +10 to Pilot checks) but landing without designated points is Hard (-20 to Pilot tests) due to antennae, cables and relays around hive-towers. Gas is pumped via plascrete-shielded, pressure-sealed arterial canals (fossae) into manufactoria and storage tanks. The fossae are a platform for a grav-rail transit system handled by tech-priests used to transport materials.
Those who live here (about 200,000) are hive dregs labouring to orders from Saelexian tech-priests under vigilant Arbitrator patrols and clerics. The healthy market constrasts with the street air (1 hour x Toughness bonus or take a Fatigue level) . Gangs will often incorporate gas masks into their colours and the sound of respirators often presage a mugging or gang war. Internal buildings have hydroponic domes and biofiltration systems that yield clean air.
The heart of the moon (Cor Cavum) is studded with noble towers and biodomes similar to the surface yet the atmosphere is better here (6 hours x Toughness bonus or take a level of Fatigue - fainting spells are sometimes known among the nobility). The triumvirate of nobles here are protected by retinues and nasal filters; the bare faced nobility and retinue broadcast edicts to the hive who aspire to these clean-living leaders of humanity.
The triumvirate of noble families oversee different functions; House Klayntire command the core of military forces on Saelex-3. House Lukiver manage the monorail and fossae operations while House Ignale manage the manufactoria through two trading houses who are rivals arising out of a deep-seated family conflict. The triumvirate makes use of neonate psykers but binds all those who serve the nobles with explosive collars - just in case.