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