Notes on this puzzle
Mine Finder #5204 hides 40 mines in a 16×16 field of 256 cells, a density of 15.6%. Every safe cell here can be decided by looking at one number at a time.
The board starts with 73 cells already uncovered, 34% of the safe ground, so the first deduction is waiting for you. Under the cover, 60 safe cells touch no mine at all, 90 show a 1 and 45 show a 2; 21 cells carry 3 or more, and the highest number in the field is 4. 10 of the mines lie along the border of the field.
Where to beginWhen two numbers share most of their neighbours, subtract one from the other.