Count down to Christmas with the ultimate daily brain challenge! From December 1st to December 24th, the Sudoku Advent Calendar 2026 (Hard Edition) offers six new puzzles every day – 144 challenging Sudokus in total. Each daily set features three demanding difficulty levels: Hard, Very Hard, and Extreme. Designed to test logic, concentration, and problem-solving skills, these puzzles provide a rewarding mental workout during the busy holiday season. The clear, easy-to-read layout and festive design make this Christmas Sudoku book ideal for experienced players, ambitious puzzle fans, and seniors looking for a real challenge. Features: • 144 challenging Sudoku puzzles • 6 new puzzles every single day of Advent • Difficulty levels: Hard, Very Hard & Extreme • Large, easy-to-read format with solutions included • Festive Christmas layout • Perfect holiday gift for adults and seniors Give the gift of daily puzzle fun or challenge yourself this December. Grab your copy today and start your countdown to Christmas!