Co-op Sudoku is a free two-player cooperative sudoku game. Both players solve one puzzle together with asymmetric information: the clues are split between you, and each player can see only their own. Enter a value and it becomes visible to both — you progress by deducing cells from your clues and revealing them, which unlocks new deductions for your partner. Neither player's clues alone are enough to finish, so the puzzle is only solvable by cooperating.
Co-op Sudoku requires JavaScript to play.