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 11 completed
Level 12 completed
Level 9 completed
Level 10 completed
Level 8 completed
Improve accurancy
Improve speed
Level 4 completed
Level 5 completed
Level 6 completed
Level 7 completed
Improve damage
Improve hp
Set fire shells
Level 1 completed
Level 2 completed
Level 3 completed
English language
Sell tower
Build knights tower
Use mini knights help
Build archers tower
Set trap
Build magician tower
Exit the main menu
Russian language
Exit the game
Enable sounds
Disable sounds