Here is the full list of all 94 Mega Mosaic achievements.
Complete 72%
Complete Region 45
Complete Region 41
Complete 69%
Complete Region 35
Complete Region 29
Complete 67%
Complete Region 37
Complete Region 34
Complete Region 30
Complete 62%
Complete 58%
Complete Region 50
Complete 55%
Complete 52%
Complete Region 47
Complete the entire western border
Complete 50%
Complete 48%
Complete Region 33
Complete Region 43
Complete 45%
Complete Region 40
Complete Region 38
Complete 42%
Complete 40%
Complete Region 31
Complete 37%
Complete 35%
Complete Region 23
Complete 32%
Complete Region 21
Complete Region 24
Complete 30%
Complete Region 25
Complete Region 18
Complete Region 27
Complete 27%
Complete 25%
Complete Region 32
Complete Region 26
Complete 22%
Complete Region 17
Complete Region 14
Complete 20%
Complete Region 20
Complete Region 22
Complete Region 28
Complete Region 9
Complete the entire southern border
Complete Region 8
Complete Region 19
Complete 17%
Complete Region 12
Complete Region 15
Complete Region 16
Complete 14%
Complete 13%
Complete Region 10
Complete Region 13
Complete 12%
Complete Region 11
Complete 11%
Complete 10%
Complete 9%
Complete 8%
Complete 6%
Complete 7%
Complete 5%
Complete Region 5
Complete Region 7
Complete 4%
Complete Region 4
Complete Region 3
Complete 3%
Complete Region 6
Complete 2%
Complete Region 2
Complete 1%
Complete Region 1
Complete 78%
Complete 83%
Complete 88%
Complete 96%
Complete 100%
Complete Region 36
Complete Region 39
Complete Region 42
Complete Region 44
Complete Region 46
Complete Region 48
Complete Region 49
Complete the entire northern border
Complete the entire eastern border