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