Tired of mastering nature and thinking, all I got was two lousy districts? Well now you don't have to stop at flattening mountains and filling in the sea, you can create underground cities or even build islands in the sky. These new decisions are more expensive, but they will give you far more than just a district or two, they come with unique jobs, event chains, and planet modifiers. The goal is to flush out one of the best perks in the game with more choices, trade offs, and depth.


Building a subterranean or floating city takes time. Starting a project takes upfront influence and energy, but mineral and alloy costs will be spread over the 5 years it takes to complete. Once you decree that a project will begin, an event screen allows you to choose what kind of sky island or subterranean city you have in mind. Each one offers both powerful bonuses and balancing maluses that will appear as a new planet modifier once construction is complete.


If you have the ascension perk, Sky Islands and Subterranean cities grant an extra district each. The perk also lets you repeated the decisions for additional jobs and districts (up to 9), for higher costs and diminishing returns. You only get the first Subterranean and Sky modifiers per planet however. The vanilla Mastery of Nature decision now grants +10% habitability instead of districts, since you can get plenty from the mod.

Subterranean cities grant 1-3 districts based on larger planet sizes, with breakpoints at size 16, 20, and 24.They are slightly cheaper, but provide less jobs/pop. It is unlocked either by the ascension perk, or Mineral Isolation (Mining tech 3.) Sky Islands grant 1-3 districts based on smaller planet sizes with breakpoints at size 20, 16, and 12. (In lore this is due to lower gravity on smaller planets, but it is also a game balance mechanic) Sky Islands are unlocked by Anti-Gravity Engineering (Housing Tech 2) or the Mastery of Nature ascension perk.

Each decision has its own background and lore, and can trigger follow up event chains that may add additional bonuses or risks. The Subterranean Foundry event chain is the most extensive, with several possible outcomes. It is essentially a backend nerf to the over powered alloys modifier, so don’t worry if that seems too good to be true. It is. This is Fine.





Subterranean Fortress: -20% Orbital Damage, +50% Defense Army Damage

Subterranean Soldiers:
-1% Leader Cost
+4 Naval Cap
+4 Defense Armies

Subterranean Foundry: +50% Alloys, -20% Habitability *Event Chain Triggered

Subterranean Forge Workers:
+5 Alloys
-8 Minerals
-0.2 Motes

Subterranean Refinery: -20% Building Strategic Resource Upkeep, +5% Housing Usage

Subterranean Refiners:
+1 Volatile Motes
+1 Rare Crystals
+1 Exotic Gases
-6 Minerals
-6 Energy

Subterranean Research Lab: +1 Physics/Engineering from Researchers, +20% Researcher Upkeep

Subterranean Researchers:
+8 Engineering Research
+8 Physics Research
-3 Consumer goods or -6 Minerals (Gestalts)





Sky Mall: +25% Trade Value, +5% Consumer Goods Upkeep (Non-Gestalt Only)

Sky Clerks:
+1% Pop Happiness
+4 Amenities
+6 Trade Value
-2 Consumer Goods

Sky Green: +10% Unity, +10 Stability

Sky Rangers:
+1% Worker Output
+8 Unity
+5 Amenities
-4 Energy


Sky Maintenance Drones (Gestalts):
+1% Simple Drone Output
+6 Unity
+8 Amenities
-3 Energy

Sky Roost: +15% Amenities (Hive Minds Only)

Sky Rookery Drone:
+10% Pop Growth Speed
+5 Amenities
+5 Unity
-5 Food

Sky Factory: +25% Pop Assembly Speed, +10% Assembly Cost

Sky Replicator:
+2 Pop Assembly
+5 Engineering Research
-8 Minerals

Sky Estate: +50% Ruler Happiness, -20% Worker Happiness (Empire Unique, Non-Gestalt Only)

High Noble: (1 per 100 pops)
+1 Leader Pool Size
+1 Influence
-5 Unity
-5 Consumer Goods


Few vanilla files were harmed in the making of this mod. In theory that means it is compatible with everything. It may be installed mid save, the decisions will appear if you meet the requirements. If you have already taken Mastery of Nature the effect will change, but you will not loose any districts already built. Overwrites mastery_of_nature static modifier. If any mod uses clear_deposits, it will temporarily remove the District/Job deposits, but they should be restored within a month or so. If its feeling frisky, sometimes the AI might use these decisions itself.

Built in compatibility with Ecology Mod New jobs will produce pollution if enabled.

If you have Mastery of Districts you will not be able to build Sky Islands on planets that already have Low Orbit Urbanisation or Subterranean Cities if they already have Subterranean Urbanisation.


Images adapted from:

• Noba
  
• JJasso
  
• nkabuto
  
• Denjoo
  
• RhexFiremind
  
• Alex Andreyev
  
• Andree Wallin
  
• Eric Spray
  
• Francesco Lorenzetti
  
• Vadim Sadovski

Language Support
German translation by Lucanoria
Russian translation by Dimonius, CrazyZombie
Japanese translation by tomezo
French localisation by Wolf of Darkness


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Local Production Planet diversification bonuses
Objective Complete GameMaster tools