Beyond Black Belt Sudoku: If you have to ask, it's too hard for you. (Martial Arts Puzzles Series)

I gave it as a gift to my husband and he likes it. Says doable but it is a little harder (he does well with everything, which tells me this version of sodoku is good

I bought 2 of these books so my coworker and I can have matches of who's the better player, and MAN! It is a challenge!

I am an advanced solver but also use online solvers if I just can't finish. All of these puzzles are solvable with one correct outcome. I have learned an immense amount by working through each puzzle step by step. If you really want to learn strategies this book is for you. I have purchased other books that appear to be just random numbers, unsolvable even with the calculator or they have many solutions. No one needs that. I am halfway through and these are well done.

This book is not for sissies. I’ve been a Sudoku fan for years and have purchased the 3 successive easier versions prior to this one.! I love a challenge and these definitely are greater difficulty than what I’ve experienced before. If you are wanting to advance your Sudoku solving skills up to becoming a grand master level…I highly recommend this book!!!!!

I got this for my Father in Law. He loves it! He lives a hard Sudoku puzzle and this one hits that nail on the head. It’s a challenge. Definitely a buy!

I'm purchasing this puzzle book for the third time. There are 300 puzzles, and there's no way I could remember the solutions, so it was a no-brainer. It's definitely a challenge, If you're not up to a very difficult level, the Third Degree Black Belt version is a good way to transition to this level. Two puzzles to a page, so no problem with print size. I highly recommend this product.

Since I way back 8 ½ years ago, in the weekly Danish engineering newspaper, one day received a double-sided writing about Sudoku, with 3 Sudoku puzzles, and there read that research had found the Sudoku to be the best training for the brain, I then started on Sudoku’s.Each day since then, I have solved at least one Sudoku puzzle, among other for getting some brain relax after all of the other hard brainwork during the day. Later it has been written that there has come another brain puzzle which should be a little bit better than Sudoku, but I like Sudoku.The first Sudoku books which I bought was the “Mensa Absolutely Nasty Sudoku”, level 2, 3, and 4, all written by Frank Long. The actual “Beyond Black Belt Sudoku”, is a bit more difficult than the Mensa level 4. But in the engineering newspaper the 3 Sudoku puzzles which then was put in were made by participants in and international Sudoku competition, and there are extremely difficult to solve, and I have newer yet in any book found Sudoku puzzles just close to these.But all together this book is a nice book, with fine difficult Sudoku’s.

I really like this book of Sudoko puzzles. Having solved so many over the years, I wanted a really hard book and this one is very, very challenging. Many times I go back and erase the errorred or unsolved puzzles and try again until I get it right. This book is NOT for the inexperienced!

Great puzzles and nicely crafted. Picks up where Mensa's Absolutely Nasty Sudoku range stops, so you should have a number of advanced solving techniques (wings, colouring, ...) in the bag before buying this! Starts with two or three advanced techniques per puzzle and gently adds more techniques/combinations. 300 puzzles in all, with two per page. Paper is good quality and there's reasonable space to make notes.

At 60-page steps through the book, plus a couple more, 26 puzzles took 800mins to average 30mins/puzzle. The quickest took 15min. but others took over 60mins, especially when I made silly mistakes or tried to see how quickly I could go.....which was another stupid mistake. I like it.

good book

Excellent

Person I bought it for is very pleased