Full list of all 102 Galactic Civilizations III achievements. It takes around 200 hours to unlock all of the achievements in the base game on Windows.
The base game contains 62 achievements, and there are 7 DLC packs containing 40 achievements.
Win as Snathi
Complete the Snathi Campaign
Win as Arceans
Win as Torians
Complete the Mercenaries campaign
Create a commonwealth
Form a government
Change your government type
Change your tax slider for one turn
Lower your taxes to 0% for one turn
Raise your taxes to 100% for one turn
Buy at least one resource on the marketplace
Sell at least one resource on the marketplace
Buy at least 10 resources at once
Sell at least 10 resources at once
Buy at least 30 resources at once
Sell at least 30 resources at once
Successfully complete a Crisis
Assign a Crisis manager
Win an Election
Win an Election with a landslide majority
Complete "Apophis" Crisis
Complete "Rogue General" Crisis
Complete "Secession" Crisis
Complete "Space Monster" Crisis
Complete "The Revolution" Crisis
Complete "The Simulation" Crisis
Complete "Brain Parasites" Crisis
Complete "Brain Trust" Crisis
Win Game playing the Terran Resistance.
Win Game playing the Onyx Hive.
Win Game playing the Slyne.
Complete the Crusade Tutorial.
Train your first Citizen.
Promote your first Specialist.
Place a spy on a foreign colony.
Conquer a planet defended by enemy Legions.
Unleash a custom Civilization on the Galaxy.
Complete the Altarian Prophecy Campaign
Complete the Rise of the Terrans campaign