Sudoku - mittel 1

Most volumes in this series are characterized by world-class Sudokus of high or extreme difficulty. Full concentration, fierce determination, and pure effort: whether difficult, extreme, or ultra - those who seek a challenge that is never too great have always turned to Heine's puzzle library. Here comes relaxation and variety. Here comes rejuvenation. Here come 500 medium-difficulty puzzles in four levels, finely graded and of the highest quality. Escape from everyday life with maximum enjoyment for short breaks!.