*** JAVA plugin is NOT required (fully compatible with Chrome OS). *** The rules of Sudoku are simple. Enter digits from 1 to 9 into the blank spaces. Every row must contain one of each digit. So must every column, as must every 3x3 square. Each Sudoku has a unique solution that can be reached logically without guessing. Game Features: - 10 different tables with 4 levels of difficulty - Create your own Xudoku - Print out your games and play them with a pen and paper - Play with different symbols - Sudoku solver included