Will Shortz Presents Double Shot Sudoku: 200 Challenging PuzzlesPaperback, 16 August 2016

It's time to jump start your mind with this shot of Sudoku! Test your skills and knowledge with these challenging puzzles found in Double Shot Sudoku.

This volume features:
-200 hard puzzles
-Big grids for easy solving
-Introduction by legendary puzzlemaster, Will Shortz!