Here is the full list of all 31 Happy Empire achievements.
Speed up your workers movement speed
Craft your first boat
Cut or collect 10 units of wood!
Finish the level without spending half of your time
Find one secret key
Choose any level on your map
Use your key to open the chest
Finish the level without spending all of your resources
Find one gold bag
Get five units of food for your workers
Find the secret chest
Cut or collect 40 units of wood!
Find the way to the secret cave
Repair 10 bridges using power ups
Collect many units of gold
Read all tips in the game
Gather 40 units of stone
Set the new time record on all levels
Don't miss any resources on each level
Command 5 workers
Complete all levels with 3 stars
Use the switch to open the gates 3 times
Gather 40 units of wood for 5 mins
Collect 40 units of frozen food
Speed up your worker's labor 10 times
Kick Moramor out from the Empire
Bring 40 units of wood to the Barracks
Cut or collect 30 units of wood!
Cut or collect 20 units of wood!
Collect 40 diamonds
Collect 80 diamonds