Samurai 8X puzzle

When I was making Sudoku Xtra 10 I wanted to put in a really big Samurai Sudoku puzzle. In the end because I had a square page area available beneath the instructions I went with a 13-grid one (just as a one-off to see what sort of reaction it got!) but I had started off intending to use an 8-grid one. It seemed a shame to let it go to waste, so I’m posting it here.

• Place 1 to 9 into each row, column, main diagonal and 3×3 box of each of the eight 9×9 grids.
• Note that, as in a regular Sudoku, only the rows, columns and main diagonals within the eight underlying 9×9 grids are guaranteed to contain all of 1-9. Any row, column or diagonal not entirely within a single 9×9 grid has no restriction on its content.

So best of luck – you don’t need it, but it might help anyway!

Killer Plus Minus Samurai puzzle

If you’re a Sudoku Xtra reader you’ll have seen these in their regular 9×9 form in both issues 5 and 6, but this is the first time I’ve made a Samurai one, and the first time I’ve posted one here I think.

This is essentially a regular Killer Sudoku puzzle, except that instead of placing 1 to 9 you must place -4, -3, -2, -1, 0, 1, 2, 3 and 4 into each row, column and bold-lined 3×3 box.  There are also two overlapping 9×9 grids to solve simultaneously.

As in regular Killer, the values in each dashed-line cage must sum to the given total, and you cannot repeat the same number within any one cage.

Good luck!

Killer Sudoku Pro 6×6 Samurai puzzle

It’s been quiet here recently – much of my effort has been going on my UK General Election site, How To Vote, although Sudoku Xtra 6 was out on Saturday too.  Anyway, there are still 10 days to go to the election but after that I’ll get some time back!

However I thought I should finally post another puzzle – so here one is.  Place 1 to 6 in each row, column and 2×3 box (rows and columns are defined by the three underlying 6×6 grids, which you have to infer from the stepping).  Also place numbers so that the value at the top-left of each dashed-line cage results from applying the operation between all the value in that cage. For subtraction and division start with the largest value.

Have fun!

Samurai 3-grid Calcudoku 6×6 puzzle

I’ve been posting a few new varieties of Sudoku puzzle in the daily puzzle section of PuzzleMix (i.e. the subscription section, which costs less than £1 a month for well over 1,000 puzzles a year). These aren’t especially unusual variations, but I’ve done a few different mixes (e.g. Sudoku-X 12×12 and Wraparound Sudoku 6×6), and I thought it was about time I posted a new mix here too.

So here’s a 3-grid Samurai Calcudoku puzzle.  You must place 1-6 in each of the 3 underlying 6×6 grids – I’m afraid these aren’t marked explicitly so you might want to draw in where the grid borders go so you don’t forget whilst solving.  Other than that, also place numbers so that the number given in each bold-lined cage results from applying the given operator between the numbers in that cage. Start with the highest number for division and subtraction. There is no restriction on repeating numbers in cages.

Good luck!

Samurai Star XXXXX puzzle

I haven’t posted a puzzle for a week (it’s been a busy week, mind!) so it’s time to make up for that, just in time for the weekend.

In this puzzle the aim is pretty simple: place 1 to 9 in each set of 9 squares starting and ending with a bold line, whether in a row or column, and similarly for each set of 9 squares starting and ending with a bold line in any of the shaded diagonals.

Good luck!

Samurai-2 Odd Pair Sudoku puzzle

One of the brand new puzzles in Sudoku Xtra issue 4 is Odd-Pair Sudoku, which I wrote about last week here on my puzzle blog. As well as some regular 9×9 puzzles I also included a large 5-grid Odd-Pair Samurai puzzle, and to illustrate how the puzzle worked I included a small solved example alongside. A full 5-grid Samurai was too big to fit sensibly in the example box, so I made a 2-grid Samurai version just for that little solution area. So that’s the solution used, but what about the puzzle itself? Well, here it is! (And so if you want to check your solution – yes, it’s printed in Sudoku Xtra issue 4! Page 19, to be precise).

The rules, in case you missed them, are really simple:

• Place 1 to 9 in each row, column and bold-lined 3×3 box of the two 9×9 Sudoku grids
• Every pair of squares with an ‘o’ circle between them must sum to an odd value. (’o’ for odd). So for example you could have “3 o 6″, but not “3 o 5″ (since that would sum to 8, an even number).

This variant is fun because it eliminates lots of possibilities from squares relatively quickly, so you’re left with more deductive logic and less pencil-mark housekeeping.

Good luck!

Samurai 8-grid Calcudoku puzzle

Here’s probably the largest Calcudoku puzzle you’ve ever seen!  It’s made up of 8 underlying 9×9 grids, each of which must have 1 to 9 placed into each row and column, and then on top of this I’ve added the familiar Calcudoku regions.

For each Calcudoku region just place numbers such that the total after applying the stated operation between the numbers in the region is the one given.  For example, 7+ could be solved by 3 and 4 (3+4). For subtraction and division start with the largest number in the region, so 1- could also be solved with 3 and 4 (4-3).

Just to make it really clear, there are no 3×3 Sudoku box regions in this puzzle – just the 8 sets of rows and columns.

Good luck!

Samurai Killer Calcudoku puzzle

I haven’t posted much here recently because I’ve been spending my time on Sudoku Xtra, so here’s a large puzzle to fill the void a bit.

This is a five-grid Samurai Killer Calcudoku:

• Place 1 to 9 into each row, column and 3×3 box of the five underlying 9×9 Sudoku grids
• Place numbers into the Calcudoku dashed-line cages to fulfil the results at the top-left of each cage.  The given operator when applied between all of the numbers must give the stated result, e.g. the solution to “5+” could be “2+1+2″. For subtraction and division start with the largest number, so for example “3-” could be “6-3″.
• Numbers can be repeated in Calcudoku cages, subject to the row, column and 3×3 box constraints.

Unlike my other puzzles I haven’t used any symmetry in this one, but I’m not sure it’s really that obvious on a puzzle like this one.  It’s not especially hard, but with so many places to potentially go it might take you a little while.

Good luck!

Samurai Star Inequality puzzle

I’m tempted to just say “good luck”, because frankly I think you’ll need it!  Not of course in the literal sense, since this is an entirely logical problem, which requires absolutely no guess work, but in terms of finding the right areas to make progress quickly.

So having started at the end, let me introduce you to this Samurai Star Inequality puzzle.  In all cases the “<” and “>” arrows point to the smaller number of each pair.  Other than that it’s a regular Samurai Star – place 1 to 9 into each row, column and marked 3×3 box of each of the 5 underlying 9×9 grids (including the one in the centre).

And now back to the beginning: Good luck!

Inequality 2-grid Samurai Sudoku

Inequality jigsaw 6×6 Sudoku puzzle

On the Sudoku Xtra forums Marilyn suggested the great idea of an inequality Samurai puzzle for issue 2, so I’ve been having a look at doing this. And here’s the first result!

I’ve started off with a regular 6×6 jigsaw Sudoku, but have added inequalities, just to get you warmed up, then I’ve included my first ever Samurai Inequality Sudoku puzzle, albeit a 2-grid one for now.

You’ll notice in both puzzles here that I have included all inequality arrows, so you have far more information than you need – this is deliberate, to make them easier! On the 6×6 puzzle there are five really nice diamond shapes in the centre area, but in general I think having all the arrows is ugly (or lazy!) so I don’t plan to include them again in future (just as I’ve never included them in past published inequality/Futoshiki puzzles).

The rules of Inequality Sudoku are pretty simple – just place the numbers as you would in a regular Sudoku (or regular Jigsaw Sudoku in the 6×6 case), but obey the less-than (”<”) and greater-than (”>”) signs between squares.  These indicate that the value of the number in a square is either less than or greater than its neighbour. And that’s it!

Good luck!

Two-away Samurai Jigsaw puzzle

Here’s a puzzle for the weekend – it’s a 5-grid samurai sudoku where in the corner grids a couple of the 3×3 regions have had their outlines tweaked to turn them into jigsaw sudoku puzzles, with full 8-way symmetry.  There are very few givens, which means you’ll need to take full advantage of the two-away markers that are also in the grid.  The grey rectangles indicate all neighbouring squares where the difference is 2 (e.g. 1&3 or 6&8) – even without precise values they can also be useful for quickly indicating where a chain of squares are all odd or all even.

Good luck!

Two-away Samurai Star puzzle

I made this puzzle yesterday but then went and forgot to post it (oops) so I’m making up for that now! It’s a Samurai Star with two-away markers, just as per the previous two puzzles I posted.

Place 1 to 9 into each of the rows, columns and 3×3 boxes of the 5 underlying Sudoku grids (including the one in the centre), whilst obeying the two-away grey bars.  Squares with a grey bar between have a difference of 2 (e.g. 1&3 or 2&4), and those without a grey bar have a difference which is not 2.

There are only 4 givens to get you going, so good luck!

Wrap-around Consecutive Samurai Star puzzle

I seem to be posting more infrequently than I intend, so I thought I’d compensate with a puzzle that would take somewhat longer to complete!  Here, then, is a wrap-around consecutive samurai star.  All squares with consecutive values (a difference of 1) are marked with white bars, including those at opposite ends of rows and columns – wherever there isn’t a bar, the values are not consecutive.

The Sudoku logic takes a few twists here and there – in fact at one point near the end you will need to spot a particularly nasty hidden set in one region.

To solve the puzzle place 1 to 9 into each row, column and 3×3 box of each of the underlying 5 Sudoku grids (including the one in the centre).  You’re only given 4 givens to get going, but with the consecutive information that’s all you need to find a unique solution.

Good luck!

Skyscraper Shuriken Samurai Sudoku puzzle

I’m glad yesterday’s Shuriken Samurai went down well, so today I’ve upgraded it to a Skyscraper puzzle (following Christine’s request for more Skyscrapers!).  This is, I think it’s fair to say, quite a bit harder than the basic Samurai yesterday was – but then any puzzle with a title this hard to say quickly really shouldn’t be able to be solved quickly either…

The rules are the same as yesterday (place 1-6 into each row, column and 2×3 box of the 13 underlying 6×6 Sudoku grids) but with the addition of Skyscraper constraints: place numbers so that the given number of digits can be ’seen’ from each external Skyscraper clue outside the grid.  From the vantage point of each Skyscraper clue look along the adjacent row/column – with higher numbers obscuring all lower numbers (or those of the same value), the clue tells you how many numbers are visible.  Check back to older puzzles I’ve posted for more detailed help.

Good luck!

Shuriken Samurai puzzle

Here’s a fun little puzzle.  A say ‘little’ because it revolves around 6×6 grids and some easy logic, although it actually involves 13 of them so it’s not exactly small either.  But I think it looks quite fun – the X shape and the X of givens makes it look a Japanese Shuriken weapon (or perhaps that’s just me), but anyway here it is.

Simply place 1-6 into each row, column and bold-lined 2×3 box of each of the 13 underlying 6×6 Sudoku grids.

Good luck!

Double Samurai Star puzzle

Following Spittledung’s comment on the Samura-i puzzle about it being nearly a double samurai star / flower samurai, I thought it would be fun to try out what exactly that would really look like – and so here is the result!

All of the 11 possible 9×9 grids are present, and you must place 1-9 into each row, column and 3×3 box of each of these underlying grids.

Good luck!

Samurai Square 9 easy puzzle

I was thinking about the tight overlay of grids in the (improved) Samura-I puzzles, and wondered what it would be like if you made a 15×15 puzzle simply by overlaying 9 Sudoku grids at all possible offsets.  The answer is attached.  This is definitely rated easy – there are lots of possible eliminations at all stages, and you shouldn’t need pencilmarks to solve it.

Of course, this principle can be extended to any arbitrary size of puzzle, but I imagine it would get a bit tedious if it was much larger…

So – can you place 1 to 9 into each row, column and 3×3 bold-lined box of each of the 9 underlying Sudoku grids in this puzzle?  You’ll need to solve all 9 grids simultaneously to reach the solution.

Good luck!

Sudoku Samura-i 9 puzzle

I decided that I didn’t like the inelegance of having 3 grids across the top  and bottom but not 3 grids down the centre column in yesterday’s Samurai-I, so I’ve fixed this for today’s puzzle – it’s pretty much the same except that now there are 9 grids here, at all possible bold-line offsets.

So can you place 1 to 9 into each of the rows, columns and bold-lined 3×3 boxes of the 9 grids in this Samurai-I puzzle?

Good luck!

Sudoku Samura-i puzzle

Here’s a new layout of Samurai Sudoku – a Samura-i, or Samurai I if you prefer! There are 7 grids here – 3 each at the top and bottom and then one in the middle too. Place 1 to 9 into each row and column of these 7 grids, as well as 1 to 9 into each bold-lined 3×3 box.

Just to re-emphasise this, there are no grids with top-left corner at offset 3 across, 3 down or at 3 across, 9 down.  There’s just the absolute centre grid and then the top row and bottom row of 3 grids each.  (Maybe this is a bit confusing – feel free to comment if you think so!)

Good luck!

Samurai Star puzzle

You might be pleased to know that today’s puzzle is somewhat easier, despite being a lot bigger!  It’s actually possible to comfortably solve this without making a single pencilmark, if you fancy an extra challenge.

It’s a Samurai Star / Flower Samurai puzzle.  Just place 1 to 9 into each row, column and 3×3 box of the 5 underlying grids (there’s one in the centre too).

Good luck!