Here is the full list of all 18 Monster Tiles TD achievements.
Pass wave 35 on Normal difficulty.
Pass wave 50 on Normal difficulty.
Pass wave 100 on Normal difficulty.
Pass wave 35 on Hard difficulty.
Pass wave 50 on Hard difficulty.
Pass wave 100 on Hard difficulty.
Pass wave 35 on Extreme difficulty.
Pass wave 50 on Extreme difficulty.
Pass wave 100 on Extreme difficulty.
Pass wave 35 on Challenge difficulty.
Pass wave 50 on Challenge difficulty.
Pass wave 100 on Challenge difficulty.
Pass wave 35 on Impossible difficulty.
Pass wave 50 on Impossible difficulty.
Pass wave 100 on Impossible difficulty.
Reach player level 10.
Reach player level 20.
Reach player level 30.