Sudoku Chain

Rules of Sudoku Chain

The Sudoku Chain is similar to the Jigsaw Sudoku, each one have regions of irregular shapes. The Sudoku Chain is composed  many groups of circles linked  together. The goal is to fill the grid with number 1 to 4 for a grid of size 4X4 up to 1 to 9 for a grid of size 9x9, so that at the end each row, column and group have each number exactly once.  To better understang, this is a puzzle with the solution.

 

So don't wait and try this puzzle.