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The book is obviously aimed at the less experienced Sudoku players, and it's excellent in that regard, but make no mistake about it- these puzzles definitely offer players a challenge! I admittedly was expecting to breeze through many of the puzzles, but thankfully that hasn't proven to be the case so far, and so I expect to get many more hours of use out of the book.
I must also say that the puzzles are presented in a very 'clean' way, each puzzle has its own page and the overall feel of the book is of a very high quality. As well as this, there are solutions for each puzzle at the back of the book - which is perfect for beginners such as myself. Overall, I'm left more than satisfied and I hope to see more Sudoku puzzle collections from the author in the future (maybe at a harder, more intermediary-level). I highly recommend it!