Here is the full list of all 20 Cliff Empire achievements.
The explosion of the nuclear power plant
More agrarian drones count than ordinary
Save 20 buildings from fire
Critically low ecology
Destroy 10 buildings in a row
Fully load trading barge
Build 10 buildings at once
The moment when two warehouses arrive at once
Earn 50000¢
Complete 25% of all researches
Complete 50% of all researches
Complete 100% of all researches
Get up by elevator of entertainment center
Fly by personal transport when all your cities have a 1000000¢ in total
Reach 200 newborn on Earth
Defrost 2000 people
Survive 20 waves of Marauders
Reach 7000 population on Earth