Here is the full list of all 54 Distant Worlds: Universe achievements.
Eliminate 10 Pirate Factions
Eliminate 5 Pirate Factions
Start 20 Wars
Eliminate 10 Enemy Empires
Conquer 100 Enemy Colonies
Destroy 1000 Enemy Troops
Defeat the Ancient Guardians
Conquer 50 Enemy Colonies
Spend at least 90% of time at War
Destroy 1000 Enemy Civilian Ships and Bases
100 Successful Espionage and Sabotage Missions
100 Successful Raids against enemy colonies and bases
Capture 100 Enemy Ships and Bases
50 Successful Raids against enemy colonies and bases
10 Successful Raids against enemy colonies and bases
Defeat the Legendary Pirates
Own an operational Planet Destroyer
Defeat the Shakturi
Build 10 Galactic Wonders
Eliminate 5 Enemy Empires
Change Government to Way of the Ancients
Capture 50 Enemy Ships and Bases
Capture 10 Enemy Ships and Bases
Change Government to Way of Darkness
25 Successful Espionage and Sabotage Missions
Eliminate 100 Enemy Characters
Build 5 Galactic Wonders
Destroy 1000 Enemy Military Ships and Bases
Destroy 100 Space Monsters
Eliminate 50 Enemy Characters
Eliminate 1 Enemy Empires
Empire Splits (Civil War)
Destroy 50 Space Monsters
Destroy 100 Enemy Troops
Destroy 50 Enemy Troops
Destroy 100 Enemy Military Ships and Bases
Conquer 10 Enemy Colonies
Eliminate 20 Enemy Characters
Destroy 100 Enemy Civilian Ships and Bases
Highest Trade Volume
Destroy 50 Enemy Civilian Ships and Bases
Destroy 50 Enemy Military Ships and Bases
Build 1 Galactic Wonders
Spend 0% of time at War
Mine Most Resources
Destroy 20 Space Monsters
Break 20 Treaties
Destroy 10 SilverMists
Destroy 50 SilverMists
Destroy 100 SilverMists
Eliminate 20 Pirate Factions
Join the Freedom Alliance
Join the Shakturi (Mutual Defense Pact)
1000 Successful Espionage and Sabotage Missions