Love doing Sudoku, especially the 12 square ones and this second book is as good as the first one was. Some are quite easy, lulling you into thinking that they're not taxing you at all and then you see it - the one square that's wrong - sometimes you can work it out without having to start again but more often than not its easier to erase it and start over. For all Sudoku fans these Daily Mail Super Sudoku books are superb - you can carry them in a pocket or bag, if you use a pencil they erase well allowing you to start over without the numbers or squares fading, there are loads to do so you can 'pick and mix' or, if like me you're more methodical you can work through consecutively. Great value for money and I can't wait for Book 3.