Tridoku is a fun and addicting logic puzzle game. Tridoku is the triangular version of Sudoku. This book is ideal for you if you love to solve difficult Tridoku puzzles. You do not need to wade through tons of easy Tridoku puzzles before getting to the real brain teasers. Once you pick up this book, you won't be able to put it back down. You have been warned! Tridoku - Hard is a collection of 276 puzzles: 216 hard Tridoku puzzles 60 extra logic puzzles Tridoku consists of nine large triangles. The numbers 1-9 must be placed into the triangular cells of each large triangle. The numbers 1-9 must also be placed in the three legs of the inner shaded triangle and in the three legs of the outer shaded triangle. No two neighboring cells may contain the same number. I guarantee that every logic puzzle in this Tridoku puzzle book has been carefully checked to ensure that each puzzle has only 1 solution. None of the puzzles in this book will appear in any of the other English PuzzleBooks.net books. Tridoku is also known as Triangular Sudoku.