Second-Degree Black Belt Sudoku(r)

My own big mouth got me in trouble and now I'm absolutely compulsive about solving the puzzles in this book. I had complained to my daughter that a friend and I were tired of not being able to find any hard sudoku puzzles. For Christmas, I received this book. Let the games begin! I have been solving these puzzles for about 10 years but at that time they were called Number Place and were contained in the Dell monthly puzzle magazines. I routinely solved all the puzzles in ink. They were very good puzzles but not nearly as hard as this Second Degree Black Belt. I even ordered special books of Number Place puzzles directly from Dell. Then I began to hear about this whiz-bang puzzle from Japan. Of course, I had to try it. Imagine my surprise when it was just my old friend the Number Place, only dressed up. Now on to this particular book. I absolutely love it. The puzzles are, for the most part, quite challenging. I have never heard of any of the techniques mentioned here by other reviewers. I just use dogged determination (and a pencil, now) and work at it until I'm done. I was beginning to wonder why they seemed so much harder than usual puzzles. I'm glad I read the other reviews posted here so that now I understand that these are different from the average sudoku. I suppose if people must use all those unusual solving techniques that would explain why I am having to re-grid some of the time. If you want to move beyond the basic sudoku puzzle level, and past what others call "hard" or "challenging" this book will be a great find for you. I tend to be very stubborn. I don't immediately "see" numbers revealed - as my friend does - but I have a huge amount of patience and even work with a separate eraser which I need - often. One little quirk about this book actually caused me to pass it over while shopping in a bookstore. I picked up the book and while leafing through it could immediately come up with quite a few numbers for spaces. I thought it would be too easy so I put it down. Once I received this as a gift I began to solve the first puzzle and learned the secret. You may get lots of numbers at first but then -- watch out, here comes the brick wall. I am going to look for more information on the solving techniques mentioned by others here. It may be just the thing I am looking for to keep me from having to erase and start over, or worse yet, re-grid the puzzle. A super good book. Be prepared to be challenged and love it!

A previous reviewer suggested the Dell montly publication for solving tips. I found it online at www.dellmagazines.com. It was very helpful, and gave me a clue to the last step for solving I haven't found on my own. If you are bored with the usual sudoku, this is the book for you, but be forewarned, it is tough, and most puzzles can't be solved without penciling in possible answers.

I wizzed throught the first Black Belt Sudoku book by another author and was getting bored toward the end. But Second Degree Black Belt by Frank Longo is awesome. These are real tough puzzles requiring an understanding of the X Wing, Unique Rectangles, Swordfish, XY Wing, XYZ Wing and other advanced strategies. Many puzzles use multiple strategies. I really liked #28 with a double X Wing based in 1's. So if you really want to dig into the more difficult strategies and avoid guessing then this is a good book to consider.

This is the most challenging classic Sudoku book I've found. It's a pleasure to spot the solution--some of which require tracing patterns in multiple dimensions. Frank Longo knows a beautiful puzzle.

These are tough Sudokus. I think these are even tougher than the "Beware! Very Challenging" sudokus from the Will Shortz series. I don't know how they compare to the ones designated "Diabolical," I haven't attempted those yet. I'm working my way through this book and solving the puzzles successfully about 70% of the time. This seems to be just right to create tension and challenge me without overly discouraging me (again I refer you to Bandura's Self Efficacy theory). But these are puzzles where you have to plug in numbers at some point and just see what happens. Here's what I do: I start off with a pen, doing all the numbers that can be deduced through logic alone. Then, I switch to a pencil. I find a box with only two options, and guess, write in a small 'A', and then follow it out to see where it goes, labelling the boxes with consecutive letters as I go so I can follow my steps backwards in retreat if necessary. Let me know if you've got a better idea. The problem with these sudokus is knowing when to abandon logic and start muscling through. It's for this reason that I think I prefer sudokus that can be solved with logic alone (although some make the case that the trial-and-error guessing is just an extension of the logical steps you are taking in your head when solving simpler puzzles). But I got this book as a gift, a little retribution for all my tough Sudoku talk, and I will not back down. Nice puzzles, well constructed for those of you into symmetry (I'm not sure why you care, but I've seen your critiques of other sudoku books). These books are also a good illustration of the fact that the number of clues filled in to start with is not directly correlated to the difficulty level of the puzzle. These look like easy puzzles at first glance, lots of numbers filled in to start with. But there is very little redundancy in the clues. I always start off hot and then hit a wall. I like the martial arts metaphor of this series. I'm flattered to be at the second degree black belt level of something I've been at for about eight months. But I saw that he has a book called second degree white belt. What is that? Some kind of veteran neophyte? Or do you have to actively unlearn something to be a second degree white belt?