The Law of Leftovers (LOL)

I promised to explain this technique, which applies to Jigsaw Sudoku (aka irregular blocks) puzzles, a while ago, so it’s time to keep the promise. You can find the same technique explained on various other sites, too. This technique is…

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Butterfly Killer Samurai

You knew this was coming – surely the largest Killer Sudoku puzzle ever! It’s a Butterfly Samurai Killer puzzle! It consists of 20 (twenty) 9×9 Sudoku sub-puzzles. There are 5 groups of 4 puzzles. Each group of 4 is arranged…

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KILLER Samurai

At long last, I just uploaded my first ever Killer Samurai Sudoku. As all our other puzzles – it’s PERFECT ;). Why: 1. It has one and only one solution. If you claim differently – triple check all the rules…

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Welcome new visitors!

Yesterday there was a post at blogs.guardian.co.uk about Killer Sudokus and a link to our site was posted. As a consequence, we’ve had some 600 referrals from that post within 12 hours (and overnight too)! I’d like to welcome our…

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Puzzle difficulty

First of all, I posted a Killer X puzzle rated THINKER for today. I would like to know how difficult you find this one. Regarding the INSANE puzzle posted on Friday – I see that there has been a lot…

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You Asked For It!

As promised, I just posted a puzzle with the rating that is currently in the lead in our poll. And that, apparently, is INSANE. This puzzle requires all Killer techniques + it requires some advanced classic Sudoku techniques (match subsets…

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Complex innies/outies – part two

I saw two comments (by Graham and David) for the puzzle posted on October 25, and I think there’s a little clarification on “complext innies/outies” that should be made here. You should look for innies/outies in more than just one…

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