The achievement states "Build every Improvement in your home system" but what exactly does it mean by "every". Some improvements are not possible as they require a planet type that may not be in your home system.



Is this possible for example if your home system does not have an asteroid belt - as without that you can't build a "Deep Space Facility"?



Also do you also need to build an "Invulnerable Empire" improvement?

It's indeed all the improvements possible, depending on your system. And yes, "Invulnerable Empire" is required too.

Many thanks - I made a list and checked it over and realised I was missing Compact Refrigeration.



For any one else attempting this - the Sowers should have 62 improvements on your home system without an asteroid belt:



Invunerable Empire

Revenue Zen

S2S Countermeasures

Cis-Oort Satellites

Collaborator Networks

Entangled Sensor Array

Permanent Vacation

Colonial Base

Heavy Isotope Refineries

Public-Private Partnerships

Xenotourism Agencies

Endothermic Structures

Interplanetary Transport Network

Extreme Option Exchange

Borer's Guild Bourse

Hardened Framing

Infinite Supermarkets

Magnetic Field Generators

Extreme Infrastructures

Elegant Networks

Unlimited Information Highways

Space Elevators

Optics Research Labs

Quantum Info Exchange

Signal Lenser Array

Self-Organizing Cities

Adaptive Industrial Systems

Non-Baryonic Shell

Self-Replicating Habitats

Psychological Insulation

Careful Sweeping

Living Habitats

Predictive Logistics

Graviton-Shielded Laboratories

Anomalies Institute

Adaptive Taxation Systems

Sustainable Farms

Epigenetic Crop Seeding

Inorganic Cultivation

Wasteless Supply Chain

AI Labor

Abundant Luxuries

Duty Free Spaceports

Uniform Shielding

Monohull Constuction

Stealth Construction

Impervious Bunkers

Community Defense

Dark Energy Rifle

Damage Control Centre

W/P Reflectors

Planetary Institute

Hydrosequencing

Permanent Perennials

Automated Investment Intelligence

Alien Communications

Corporeal Freedom

Inert Hulls

Massively Parallel Countermeasures

Cloudrippers

Starstrikers

and Compact Refrigeration



If you have an asteroid belt add Deep Space Facility.



Intensive Cultivation Logistics is replaced by Inorganic Cultivation for Sowers

Colonial Rights is replaced by Elegant Networks for Sowers

Localized Apocalypse mentioned on Wiki does not seem to exist?

I just completed this as the Automatons lacking an asteroid belt, so to clarify that it is all improvements for your system.