Dan Croker has two obsessions - Sudoku and frogs. So he just had to combine his loves and make the Famous Frog Sudoku books. This Take A Break Series Book contains 500 very hard puzzles. There are 4 puzzles per page and a fun and colorful cover that is sure to brighten your day. Solutions are given at the end of the book. More Famous Frog Sudoku series - Beach Bum Series, Bathroom Sudoku, Brain Yoga, Sharper Pencil Series and Travel Series.