Here is the full list of all 10 Unlock The King achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Finish 100 levels
Finish 90 levels
Finish 80 levels
Finish 70 levels
Finish 60 levels
Finish 50 levels
Finish 40 levels
Finish 30 levels
FInish 20 levels
Finish 10 levels