Daily Kaodoku

Difficult Sudoku game with Smiley faces. Each of the unique 9 smileys has to appear only once in every 3x3 box, row and column. Every smiley is a combination of 3 different mouths and 3 different shapes. This way you have also other solving techniques then unique smileys. For example: every row, column and 3x3 box has exact 3 square shapes.