In this game there will be a grid of 9 x 9 blocks, this grid is further divided into 9 subgroups of 3 x 3 blocks, in addition to that, the blocks will be grouped by red clue lines marked with a number. The object of this game is to fill in all the blocks with 1 - 9 without repeat within either the rows or columns or the subgroups or the clue groups. Moreover, the numbers in a clue group must add up to the number given in the clue. This game is similar to sudoku but more challenging.
How to play sudoku games:
There is really only one rule to Sudoku: Fill in the game board so that the numbers 1 through 9 occur exactly once in each row, column, and 3x3 box. The numbers can appear in any order and diagonals are not considered. Your initial game board will consist of several numbers that are already placed. Those numbers cannot be changed. Your goal is to fill in the empty squares following the simple rule above.