Here is the full list of all 10 Mouse Dreams achievements.
You completed the first level.
You have completed 5 levels.
You have solved 10 levels!
You have completed 20 levels!
You have completed 50 levels.
You have found a hidden red cheese!
You've munched 10 red cheeses!
You've found ALL the hidden red cheese!
Completed the game!
You've found a new hat.