Sudoku Puzzles by SudokuPuzzFillin the blank cells using numbers 1 - 9. Each number can appear only once in each row, column and block. A "block" is 9 cells, three cells across and three cells down. There are 9 "blocks" on the game grid. Detailed instructions are found in the "How To" link on the upper right of puzzle. Choose your difficulty level: "Very Easy", "Easy", "Medium", "Hard", and "Fiendish" by clicking on "New Puzzle" link. This game is run from the SudokuPuzz server. and will work only so long as that server does.