Sudoku-ku

Sudoku, made for people who actually want to think. Five difficulty levels, from a relaxed Easy warm-up to a true Extreme mode built on genuine 17-clue puzzles — the mathematically-proven minimum for a uniquely solvable grid, not just a harder shuffle of the same generator. Every puzzle is checked to require real technique, not luck. SOLVE YOUR WAY Pencil marks with one-tap auto-notes, and notes clear themselves automatically as you fill cells in Unlimited undo and redo Mistake highlighting checks your entries against the actual solution, not just row/column/box duplicates Stuck? Hints explain the technique — naked single, hidden single, or the logical deduction that applies — and why that cell has to be that digit, so you learn something instead of just getting the answer DAILY CHALLENGE One shared puzzle every day, the same for everyone, with its own streak tracked separately from…