Here is the full list of all 29 Kingdom Defense achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Level 12 completed
Level 10 completed
Level 11 completed
Level 5 completed
Level 6 completed
Level 7 completed
Level 8 completed
Level 9 completed
Sell tower
Set fire shells
Russian language
Exit the game
Level 1 completed
Level 2 completed
Level 3 completed
Level 4 completed
English language
Improve damage
Improve hp
Build knights tower
Use mini knights help
Improve accurancy
Improve speed
Build archers tower
Set trap
Build magician tower
Exit the main menu
Enable sounds
Disable sounds