Here is the full list of all 20 Cliff Empire achievements.
Save 20 buildings from fire
Build 10 buildings at once
The moment when two warehouses arrive at once
Critically low ecology
More agrarian drones count than ordinary
Earn 50000¢
Complete 25% of all researches
Complete 50% of all researches
Complete 100% of all researches
Fully load trading barge
Get up by elevator of entertainment center
The explosion of the nuclear power plant
Destroy 10 buildings in a row
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