The New York Times' crossword editor and NPR's puzzlemaster invites
you to try your hand and mind at solving some incredible brainteasers in
Will Shortz Presents Ferocious Sudoku: 200 Hard Puzzles.
Perfectly sized for traveling with big grids for easy solving, discover
if you are tough enough to take on the challenge of this collection of
200 devilishly difficult sudoku puzzles!