Here is the full list of all 50 Citizens of Earth achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Defeat Colonel Cookie.
Defeat the Hippie Guru.
Recruit 25 citizens.
Receive 2,500 damage in combat.
Use 25 items.
Find 100 treasures.
Earn $10,000.
Defeat 250 enemies.
Spend $3,000.
Ambush 10 enemies in a row.
Defeat the Puppet President.
Deal 10,000 damage in combat.
Collect 100 items.
Get one citizen to Lv 20.
Find 45 treasures.
Spend $1,000.
Get one citizen to Talent Lv 3.
Earn $3,000.
Discover 30 locations.
Discover 20 locations.
Defeat Mr. Mocha.
Collect 30 items.
Deal 2,500 damage in combat.
Receive 500 damage in combat.
Find 15 treasures.
Defeat 50 enemies.
Deal 500 damage in combat.
Recruit 5 citizens.
Earn $1,000.
Discover 10 locations.
Defeat the Opposition Leader.
Defeat 1,000 enemies.
Receive 10,000 damage in combat.
Recruit all 40 citizens.
Spend $10,000.
Collect 300 items.
Use 75 items.
Use 150 items.
Defeat Agent D.O.O.M.
Defeat DJ Voodoo.
Defeat Honcho Villa.
Defeat the Mishmasher.
Defeat the Alien Commander.
Defeat the Secretary Supreme.
Earn $100,000 in the Casino.
Enroll 9 citizens simultaneously in School.
Get all citizens to Lv 30.
Complete all Wanted Poster quests.
Complete all Extermination quests.
Complete all Photography quests.