Here is the full list of all 12 Symmetry Lines achievements.
Line 2 unlocked
Line 3 unlocked
Line 4 unlocked
Line 5 unlocked
Line 6 unlocked
Solved all puzzles
sum of wasted moves in 36 levels ≤ 100
sum of wasted moves in 36 levels ≤ 50
sum of wasted moves in 36 levels ≤ 10
sum of wasted moves in 36 levels ≤ 5
sum of wasted moves in 36 levels ≤ 1
sum of wasted moves in 36 levels = 0