Looking for a great sudoku pen that can write small, not smudge, and still be legible. If anyone has any suggestion. I started doing these 25x25 sudoku puzzles and it's really hard
25x25 Sudoku Puzzle Book Medium: Irregular Sudoku Variations Brain Logic Games For Adults: Amazon.co.uk: Edward Sevensam: 9798835185924: Books
25x25 Sudoku Puzzle Book
Sudoku Puzzle 25X25, Volume 1 eBook by YobiTech Consulting - EPUB Book | Rakuten Kobo United States
Sudoku 25x25 on the App Store
25x25 Sudoku: 100 sudoku puzzles complete with solutions (Paperback) | Little Shop of Stories
25x25 Sudoku: Keep Your Brain Active And Engaged With 100 Giant Hard Puzzles, Ultimate Sudoku Puzzle Book With Complete Solutions, Vol 01 by Suzanna Tahlia | Goodreads
Jacob James Sudoku 25x25 50 Giant Medium Sudoku Puzzles (Paperback) | eBay