Here is the full list of all 16 Slither Link achievements.
150 levels has finished.
10X10 levels has finished.
100 levels has finished.
7X7 levels has finished.
50 levels has finished.
5X5 levels has finished.
25 levels has finished.
10 levels has finished.
5 levels has finished.
The tutorial(1-2 level in 5x5) has finished
200 levels has finished.
250 levels has finished.
300 levels(All levels) has finished.
15X15 levels has finished.
20X20 levels has finished.
30X25 levels has finished.