Monthly Masyu
A 20×20 Hard marathon — 400 cells and a loop that winds across the whole board. Chip away at it all month; every line is saved.
Masyu hard
Tips for big boards
- Work in quadrants: finish the forced pearl moves in one area before moving on.
- Track loose ends carefully — premature loops are the most common mistake on large boards.
- Use the Check button to confirm a region before building on it.
Ready for even bigger? Try 25×25 Masyu.