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Train your brain with a mega-mind workout that lasts for a full year! This big book of Sudoku contains 365 of the wildly popular puzzles, designed to take solvers from novice to expert. Start off easy, with medium-level Sudoku, move on to the harder grids, and finally try your luck with the tear-your-hair-out very, very HARD conundrums. Even though you're filling in the boxes with numbers, there's no math skill required; just pure logic. The introduction provides basic strategies, explaining how to exclude possibilities and leading you through a sample puzzle in great detail. By the time you've made it through this collection, you'll have sharpened that gray matter and built those mental muscles.