Here is the full list of all 42 Rebuild 3: Gangs of Deadsville achievements.
Complete the final scenario city
Get any survivor to defense level 20 (includes equipment)
Have 365 food at once
Complete the Return to New York questline
Complete every research project
Repair an airplane and fly away
Fix a Power Plant
Generate a surplus of 50 food per day from farms
Kill 10,000 zombies cumulatively
Find 100 items while scavenging cumulatively
Destroy every faction on the map
Destroy any faction
Be allies with every faction in the city
Become allies with any faction
Reclaim the entire city
Produce 100 items in the workshop cumulatively
Kill 1000 zombies cumulatively
Finish any city on any difficulty
Complete scenario city 1
Get any survivor to level 10 in some skill
Build a City Hall
Kill 100 zombies cumulatively
Finish any city on Hard difficulty
Finish any city on Impossible difficulty
Finish any city by day 50
Use 50 bath salts in one game
Have a survivor with 10 in every skill
Equip a Rocket Launcher
Light off Fireworks
Equip every survivor with a gun
Equip 10 animals
Have 5 hospitals, 10 medkits, and 100 medicine at once
Have 100 survivors at once
Kill 100,000 zombies cumulatively
Become Gustav's friend and get his special deals
Declare peace with a faction
Eat enough people to be considered evil cannibals
Complete the Gangs of Deadsville questline
Have 50% of survivors become cultists
Fully infect the Dahlias with your cultists
Complete the Pig Farmer questline
Discover the true origin of the disease