Here is the full list of all 11 Shadow Mist achievements.
The first fall
First contact with a thorn
First contact with a monster
Clear all stages with less than 20 deaths
Clear all the mist for the first time
Clear all of the mist
Don't forget the rouge
Music and Visual has no boundary
Bread will have of, the milk will also have of
Jump on the bed 500 times
Clear all stages