About the game
Nine boxes of 3 x 3 cells make up the field in Sudoku - Number Games. Digits 1 through 9 have to land in every horizontal line, every vertical line and every box, and a digit can show up just once inside each of them.
Pick an empty cell, look at what already sits in its line and its box, then tap a digit that breaks nothing. Climbing to a higher level means heavier boards; older levels stay reachable for a calmer round. Counting and memory do the work here, and a single grid can eat a whole break.