Here is the full list of all 18 Mossy Pixels achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Uncover 150 patterns.
Uncover 140 patterns.
Uncover 130 patterns.
Uncover 120 patterns.
Uncover 110 patterns.
Uncover 100 patterns.
Uncover 90 patterns.
Uncover 80 patterns.
Uncover 70 patterns.
Uncover 60 patterns.
Uncover 50 patterns.
Uncover 40 patterns.
Uncover 30 patterns.
Uncover 20 patterns.
Uncover 10 patterns.
Change the color palette.
Uncover your first pattern.
Let the game pick a random level for you.