Just like for my previous test Copy Paste, I have gathered a few links to more practise material. The following puzzles appeared either in the puzzle portal of Logic Masters Germany or in a German Sudoku Championship.
If you have any question about one of these puzzles or regarding ‘V2V’, please do not hesitate to ask; I’ll be happy to answer.
Greater than Consecutive: Hard Hard
Clone: Medium
Primes: Easy (Different notation of the primes!)
Thermometers: Medium
Rank: Medium
Even Sandwich: Medium
Sum Sandwich: Hard
1~9: Medium
Frame 1~9: Hard

1~9:
WPF Grand Prix German round (Instruction booklet) puzzle 9
WPF Grand Prix German round (Contest) puzzle 9 Password: MzrM65W1fdE2NKiR
Sudoku Cup 4: Link

Even Sandwich, Rank and Clone were inspired by:
LMI sudoku test Classics vs Innovatives

GT Consecutive was inspired by:
LMI sudoku test Sudoku 8x8

For Thermometers there are many examples available, I think.

I have planned to publish a few more practice puzzles on the website of LM Germany before the test.
I will keep you all informed after I have done so.

Have fun!

A question about rules:
For the hot/cold thermometers, does the choice of hot or cold have to be consistent within a given thermometer?
This didn't happen in the practice puzzle, but in principle would "1234(5)6789" have been a valid thermometer for that puzzle?

Yes, the choice of increasing/decreasing has to be consistent within a given thermometer.
The example of 1234(5)6789 is not a valid thermometer.

I have added two more practise puzzles on my user page at Logic Masters Germany:

Shaken Clones and Hot/Cold Thermometers

The rules for Hot/Cold Thermometers raised questions, here as well as in the puzzle portal, so I have added a sentence to clearify things. A new IB will be uploaded, meanwhile the full instructions for Hot/Cold Thermometers are written here:

From the bulb to both ends the digits in each thermometer-shaped region should be either in increasing or decreasing order. This increasing or decreasing order has to be the same in both directions.

Two rules question:

*) Clones: The rules say: "Cloned shapes may be rotated (not reflected!)." What happens in the case that a clone shape is a 1xn rectangle?
Let us assume that two corresponding clone shapes are I-shaped pentominos. For simplicity, both shall be horizontal. Is it allowed that one shapes contains the numbers 12345 and the other contains 54321.
By the rules this is allowed (may be rotated) and forbidden (not reflected). Please clarify (or tell us, that such shapes will not occur). :-)

*) Sum Sandwich: Here the rules seem perfectly clear to me but I would appreciate a confirmation...
Let us assume that two numbers are given outside the same row/column of the puzzle, say 3 6. Then 3 must be sandwiched by 1 and 2 and 6 must be sandwiched by 1/5 or 2/4. Those sandwiches may overlap, i.e. 23165 is valid.
The sequence 1 3 6 8 is not valid for this example (with the wrong thinking that the numbers 1 and 8 equal 9 and sandwich the numbers 3 and 6 equaling 9 also).

CLONES: If a clone shape is a 1xn-rectangle, reflection gives the same result as rotation, so in this case reflection is also allowed. In the practise puzzle (link also in my thread above) 1x2 and 1x3-shapes occur.

SUM SANDWICH: 23165 is a valid, partly overlapping solution for 3 and 6 both being sandwiched in the same row/column. I have written this example puzzle (link also in my thread above) on purpose with a long chain of overlapping sums in column 2.

New practise puzzle added in the portal of LM Germany:
Perfect Squares. Enjoy!

Last practise puzzle will be published coming friday at noon (22 March).

In the SHAKEN CLONES, the rule is "Each shape is cloned one or more times."
Are all same shapes clones to each others or is it allowed to have 2 different pairs of clones for 4 same shapes, for example?

I look forward to this test. Some interesting new variations here !

Fred

IB has this clarification now.

Hi Fred,

No, this is not allowed.

Selected examples can be solved online now.

As promised I have uploaded the last practise puzzle in the puzzle portal of LM Germany:

Rank Killer

With this last one I hope all participants can have a decent preparation to the test.

Good luck to all, and more important: Have fun!

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Many puzzles were worth too much or too little
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Many puzzles were worth too much or too little
What was your opinion of the booklet formatting and printing?	Just right

Thanks for an interesting set of puzzles.

I will be interested to see the answer for Rank Killer as I think I must have misunderstood the rules. I got stuck three times in the bottom left corner (a delay which later meant that I missed out on typing the answer for Holt/Cold Thermometer by about five seconds ). In case there is a problem with Rank Killer, I'll explain my logic.

r9c1 was the 5 of 1/2/3/5. The vertical 1/2/3 meant r5c2 had to be 4 rather than 3 with r7c1 as 8 to be third and r5c1/r6c1 as 6/9. r9c6 had to be 4 because r9c1 was already 5, which also gave 7/8/9 from r9c7 onwards. On r9, that left 1/2/3/6 to place. r9c4 had to be at least 3 to be third but could not be 6 because 6 plus a higher number in r7c4 would be too much for a four-cage total of 14. So, r9c4 is 3. That makes r8c4 and r9c5 1/2. 1+2+3+8=14 making r7c4 8 which clashes with r7c1.

Hope that made sense. Thanks again, David.

Hi David,

Sorry to read that you had a lot of problems with the rank killer.

I have planned to write some lines about each puzzle as soon as the test is over, with at least the first important steps in the solving process. I hope that will help.

Thanks Richard. I enjoyed the puzzles - thank you for all the work you have put into creating them. David.

I think you'll find you eliminated another possibility here itself, for R5C2 :)

Oh, now I see - thank you !

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Can I get a Mulligan? Really nice puzzles, except my brain wasn't in the mood. Broke both the Clones and Greather than X 3 times. Knew my submission for the second one would be wrong, but had no time left, so thought. you never know.

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Too many hard puzzles
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

A beautiful test.Many thnks to the author for this wonderful test.I had great fun solving the test.
Got a deja vu of the masyu puzzle in puzzle marathon after seeing the primes without any dots.It is a good way to take the players by surpise.The conventional thinking gets disrupted totally.I was hoping to tackle this puzzle by making pencil marks of 1379 at the end of the dots. Because of the surprise factor this puzzle took me more time to solve than the hot/cold thermometer!
Hope to solve the remaining puzzles some time later.
One thing i would love to add here is the practise puzzles that the author posted before the test laying the foundation for the test beautifully.
Excellent test!!!I really enjoyed it!!

Thanks a lot for your kind words!

I will be happy to post full feedback on (practise) puzzles after the test is over.

What do the instructions mean, in Perfects Squares and Primes, when they say "This constraint is not valid for vertically adjacent cells"?

Does it mean vertically adjacent cells aren't constrained, so they can even have or not have the pattern? (square or prime)

Or does it mean no two vertically adjacent cells can have the pattern? If the latter, kropki-like puzzles usually handle that by the presence or absence of a square or diamond, without a confusingly worded rule.

...without a confusingly worded rule...

Of course I don't want to confuse solvers, but I thought this was the best way to clarify the rules. Sorry if it's not...

What I mean is that it doesn't matter what digit combination appears in the columns, primes, squares, doesn't matter, so your first interpretation Does it mean vertically adjacent cells aren't constrained, so they can even have or not have the pattern? (square or prime) is correct.

Thanks, that was my guess. Perhaps "constraint does not apply" instead of "constraint is not valid"?

Also, working the IB examples clarifies the question. Thanks!

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Thanks for this great test. I really enjoyed solving it.

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount

Thank you for this wonderful test !

The set was really enjoying, well balanced, and all sudokus were perfectly constructed.

On a personal note, I broke the thermo-sudoku 2 times and hadn't enough time the 3rd time (there was 3 minutes left). It's a pity, because without these mistakes, I think it was within my reach to solve all sudokus in 120 minutes.

Fred

P.S.: and I forgot to say that I look forward to solve more of your sudokus during the next DSM (and I hope without mistake)

Edited by Fred76 2013-03-24 7:36 PM

That is interesting co-incidence.

Phew !

I didn't remember that ! Perhaps next time I'll skip the thermo until I solved all other puzzles !

Fred

I went straight for the Greater Than X and systematically tried X=1,2,3,4,5. None worked for me. Can't wait for the answers and the intended solving path.
Basically this was a 100 minute test for me because that first puzzle took away 20 minutes with no points. :(

Great sudokus from Richard as usual. I liked how there's plenty of practise puzzles that are available before the test.

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Too many hard puzzles
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

I hesitated to write that the Greater than X was overvalued, because I found it not so hard...

Here is a way you can find X:

-box 4: there are 4 pairs: the only possibilities are 1,2,4 or 5.
-you can eliminate the 2 with the 4 and 6 in Row 9 (4 cannot be next to the 6). It remains 1,4 or 5
-you can eliminate the 5, because in box 8, 1 has to be "X-consecutive" and it cannot with the 6, already present in the box. ->1,4
-It's a bit more difficult to eliminate the 1: If you place the 2 in R1C6, then you have 1 and 2 in R78C4, then it's impossible to place the 3 in box 8 (cannot be next to 2 or 4, and it cannot be consecutive to another digit).

So X=4 !

Hope that helps !

Fred

Actually, I got X=4 very easily, but found the remaining Sudoku very difficult.

I have written a full walk through for this puzzle, that will be published immediately after the test is over. The puzzle has a perfectly logical solve if you know the way.

But I like to publish the notes to all puzzles at once, so I ask for a little bit of patience...

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Me too, getting X was really quick. The rest was a big problem and I still kept breaking it.

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Thanks Richard! Nice puzzles!

What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Richard, thanks for excellent test (nothing less expected).

Branko

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Yes I got X=4 as well. I had the 1-5, 2-6, 3-7, 4-8 pair laid out quickly and it didnt work.
Then I found out that 5-9 was also a pair and it still didnt work... :(

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Delightful puzzles! Thanks for a great contest!

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

With me also the same problem. I got X=4 easily but still not able to solve this puzzle. Looking forward to logical steps to solve it from author once the test is over.

How balanced do you think the puzzle types of this test were?	A bit skewed
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	A bit too many puzzles
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Results show some puzzle ratings. Where can puzzles be rated?

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

On the submissions page, under the puzzle name, you'll see 10 gray stars. Just drag mouse over and click at the number you want to give for the puzzle and they'll turn yellow.

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

This test started off great for me, started at the bottom and was flying until I got to rank killer and then I broke it twice which cost me a lot of time... looking forward to seeing the answer/result on it.

Thanks for a fun test though!

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

I wish I hadn't made a typo, and I wish I'd learn that I always get stuck on Odd Even type variants and done the Frame 1~9 instead of getting stuck for a long time on the Even Sandwich. Otherwise, it was a fun test. Thanks Richard! :)

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	All puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

V2V is over. Congratulations to deu for winning this one, surprisingly his first LMI sudoku test win.

Congratulations to deu, kota and TiiT for taking the top positions.
That was really a photo-finish, with less than half a minute difference between the first and second position!

For me it has been an exciting (extended) weekend again, eagerly looking to all the performances 'behind the screens'.

Almost 300 players participated in this test. I was very happy to see a lot of 'new' players, who participated in the Grand Prix for the first time at LMI, and now returned to participate again. Thanks for that to all those players, and let's hope they keep coming back for future tests!

Like I did after my previous tests, I want to write some lines again here in the forum.

The idea for this Variations to Variants came in augus, right after Classics vs. Innovatives.

Here is a quote from me in the forum thread of Classics vs. Innovatives:


Since my main hobby is creating puzzles in general and sudokus in particular, I am often busy thinking about new variations to this theme, so the idea of V2V was born in august last year.

While creating the set, I first looked back to Copy-Paste; no less than 16 players solved all puzzles (some with mistakes, but still), so the new test could become a bit harder. With 5 finishers now, that goal is achieved, although my expectations were that the fastest players could finish in less than 100 minutes.

I had some reservations about putting so many new or 'newish' things in a single test; it might scare off players when there is not a fair share of well known stuff. So in that way I am really delighted to see a massive number of participants.

Some of the variants in the test require a bit different approach than we are used to, so I have written notes to all puzzles in the test, including the first steps in the solving process. I will post them in the forum today, one after another.
I would be very happy when players learn from that, but I would also be very much interested to read if the way I went through the puzzle is the most efficient way. From that perspective I can learn from (top) players as well, so you are all invited to response!

Notes to V2V (I)

I will write the notes for two paired puzzles per thread, so the forum is not spoiled with a single thread of 3 pages.
I am considering putting all the notes in some kind of 'solution booklet', if it fullfills a need. Please let me know.

So here are the notes to the first two puzzles:

V: GT Consecutive
Normally in consecutive sudokus not so much givens are necessary, let alone in a consecutive in which you know what is the greater and what the smaller digit.
For this test I was in the mood for working with digits 1 to 9 as givens, especially since you can make a relative easy puzzle as a start of the test; besides, not many GT signs are necessary in that case.
Of course the start of the puzzle is {46} in R4C6 and R6C4. 123 and 789 can be placed in the middle block as wel as 4 in R4C6 and 6 in R6C4. Next column 7 can be filled completely: R6C7 = 4; R4C7 = 1, R89C7 = 78, 2 in R1 and 5 in R2.
No further problems or tricks in this puzzle.

V2V: Greater than X
Obviously a puzzle that a lot of people skipped, or had problems with, although some people didn’t encounter any problems at all.
Here we go:
Two of the few given digits in the grid are placed in box 8, so the puzzle is pinpointing in this direction for the first clue(s).
First the value of X:
Because of the 6 with the greater sign, X has a maximum of 5 and is not 2. It is also not 5, because of the 1 with smaller sign in row 1. The 1 in Block 8 is placed in R7C4 [Note: 1 can’t be in R8C6 because it conflicts with the smaller sign in row 1] below a GT-sign, so X is also not 3. So there are still only 1 and 4 left as possibility for X.
Try X = 1: R7C4 = 1; R8C4 = 2; 3 cannot be placed in any of the 3 remaining cells.
So: X = 4.
[Note: determining X is not 3 can be done straight away: Block 4 contains 4 GT-signs, covering 8 cells, so X is not 3.]

Let’s start solving.
R5C2 = 1
Explanation: With X being 4, 1 or 9 is not used in the four different ‘pairs’ in 3x3-Block 4.
With 1 or 9 being unused, 5 is placed in one of the ‘corner’ cells of Block 4. Since all these ‘corner’ cells are the smallest of the ‘pair’, 5 goes together with 9 and 1 is unused, placed in the middle of the block.
R1C6 = 5; R9C7 = 2; R7C4 = 1; R8C4 = 5; R8C6 = 3; R7C6 = 7
R8C2 = 4; R9C2 = 8 (Only possible combination that is left here)
R7C5 = 8 (Only possibility for 8 in row 7)
R8C5 = 2; R9C5 = 9; R2C5 = 4; R2C6 = 8
3 in row 9 in R9C89:=> 7 in Block 7 locked in R9C13.
And then a very mean naked single: R8C3 = 6.
R7C1 = 2 (Only possibility in Block 7)
5 in Block 7 in R9C13 :=> R9C13 is {57}
R8C1 = 1; R7C3 = 9
R6C2 = 6; R6C3 = 2; R6C9 = 1; R7C9 = 5; R9C9 = 3; R9C8 = 1; R8C8 = 7; R4C6 = 1
R2C3 = 1 [If 1 is placed in R3C3, there is also a ‘pair’ in R12C3, but there is no GT-sign.]
R3C2 = 5; R4C2 = 7; R4C1 = 3
And the rest shouldn’t be any difficult at all.

Notes to V2V (II)

V: Clones
I like to work with diagonal symmetry, but it is not often used in sudokus. For this clones sudoku I thougt this type of symmetry was very suitable.
The first step in solving is to realise that R6C9 = R9C7 & R7C9 = R9C6.
R7C7 = 6; R8C8 = 5; R6C8 = 2
6 is not in tetris-shape in C12 :=> R2C4 = 6 & R5C3 = 6
All 6's can be placed now
R6C2 & R2C6 = 3
Rest should go easy from here

V2V: Shaken Clones
After I constructed a Clone sudoku for the advent calender at LM Germany, I thought it would be a nice idea too to work with shapes containing the same digits, but without the restriction of fixed position of digits. By keeping the shapes inside 3x3-boxes, I had a good way keeping the number of givens to a minimum, without getting too hard.
The triomino clone contains digits 237, so R4C8 = 2; R45C9 = {37}
The 5 in the 3x3-block bottom left goes into the square clone, so R3C8 cannot be 5 :=> R3C5 = 5; R2C5 = 8; R2C4 = 4
The pentomino clone contains 4 (Block 5) and 1 (Block 1), so in column 1 the 4 goes into R4C1.
1 in row 9 must be in R9C8.
R6C9 = 1; R2C9 = 5; R8C1 = 5;
8 is not in pentomino shape:=> R9C9 = 8
4 is not in square shape:=> R8C9 = 4; R7C9 = 6; R1C9 = 9
6 is not in pentomino shape:=>R8C5 = 6; R8C6 = 1; R7C5 = 9
9 must be in pentomino shape:=> R5C4 = 9
6 must be in square shape:=> R2C8 = 6
The rest should be pretty much straight forward

Notes to V2V (III)

V: Perfect Squares
One of the two 'joke'-puzzles in the set. I thought it would be fun to include the longest possible chain of consecutive squares as a starting point (81649 in row 5).
This puzzle doesn't contain difficult steps, although you have to realise that no perfect square may be formed when there is no dot. A lot of players found solutions that contained one or more perfect squares where it wasn't allowed, so the successrating for this puzzle is not so high.
In most tests, the puzzle that is submitted the most is either the first puzzle or the one with the least points. Perfect Squares isn't one of those, but it is submitted the most, and also the most number of times with errors.

V2V: Primes
This is the other 'joke'-puzzle in the set. There are multiple examples of puzzles where a constraint doesn't appear at all in a puzzle. For that reason I created this 'primeless primes'. It wasn't easy to find a solution for the grid, but after that a nice, easy puzzle came out. It's important to realise the key role for the 3. Only 63 and 93 have a 3 as second digit without being a prime.

Notes to V2V (IV)

V: Thermometers
A lot of thermometers are built on a few given digits and long thermometer shapes. Not much have diagonal lines. Thermometers had to be one of the easier puzzles, since it is a well known variant, so I used pretty much givens and a straight forward route through the puzzle.
R46C5 = {78}
R3C3 = 8; R2C4 = 9; R7C2 = 3
R2C6 = 8; R1C7 = 9
R8C4 = 8; R9C3 = 9
R7C8 = 1; R3C5 = 5; R2C5 = 2; R8C5 = 3; R7C5 = 6; R3C8 = 2

V2V: Hot/Cold Thermometers
I had the idea for this puzzle type already for a long time, it just didn’t happen to make a few puzzles out of it. In fact the type is a blend of Increasing and Thermometers, with the bulb in the middle of the line.
There are a few specific moves/conclusions in this puzzle:
R7C5 = 9; R5C7 = 9; R2C7 = 7; R2C8 = 8;
R2C4 = 3; R2C3 = 5; R2C5 = 2;
R5C8 = 1; R4C6 = 1
9 in row 3 in Block 1; 9 in C3 in Block 1 :=> R3C3 = 9; R1C3 = 2; R3C1 = 6
R5C2 = 2; R7C2 = 5;
R3C79 = {12}; R3C8 = 3; R1C7 = 5; R6C8 = 5; R7C8 = 4
4 in Block 7 locked in R89C3 :=> R5C3 = 7/8; R4C2 = 6/7; R4C3 = 7/8; R4C4 = 8/9;
R4C2 = 6; R6C3 = 3
R7C3 = 1; R4C5 = 5
4 in R5 locked in R5C46; R8C5 = 4
Not much troubles to be expected after this stage.

Notes to V2V (V)

V: Rank
Rank was one of my favourite puzzles in Classics vs Innovatives, so I deliberately wanted to include such a puzzle in one of my own tests.
Towards the end it contains a bit of a tricky step, that can be overseen easily.
R9C8 = 7; R2C5 = 9; R3C5 = 1; R3C8 = 3; R3C4 = 6; R3C7 = 5;
R3C2 = 8; R3C3 = 2; R2C6 = 8; R4C6 = 9; R9C4 = 9; R8C5 = 8;
R9C5 = 4; R7C3 = 5; R9C6 = 5; R8C13 = {34}; R7C2 = 9; R8C9 = 9;
R5C3 = 9; R6C8 = 9; R9C9 = 6;
R1C8 + R2C7 = {46}; R2C9 = 1; R1C9 = 8; R2C3 = 7; R7C8 = 1; R8C4 =1
Towards the end, placing the 7 in Block 4 is a crucial step in getting the solution logically. By that time you know that R6C4 = either 7 or 8. That means that the 7 in block 4 can’t go in R4C2, since R4C1 must be 8 and no possibility is left for R6C4 in that case.

V2V: Rank killer
As soon as I saw the Rank sudoku for the first time, with the dotted outlined boxes, I realised that this puzzle type could be combined with killer in a beautiful way, so that variation to a variant was settled early in the puzzle creating process for this test.
R9C1 = 5; R789C2 = {123}; R9C6 = 4; R9C789 = {789}; R9C3 = 6
R9C4 = 3; R8C4 + R9C5 = {12}; R7C4 = 8; R7C56 = {56}; R5C6 = 1; R6C6 = 2;
R7C1 = 7; R7C3 = 9;
Maximum for R7C89 = 7 (3+4); maximum of R8C9 = 6; R6C8 = 9; R7C8 = 3; R7C9 = 4; R8C9 = 6
R8C2 = 3; R5C1 = 9; R3C5 = 8; R4C6 = 8; R5C2 = 5; R6C1 = 6; R5C4 = 4; R34C4 = {79};
R2C45 = {12};
1 in Block 3 locked in R13C8; R6C9 = 1; R3C6 = 3; R1C5 = 4; R1C4 = 6; R6C4 = 5;
R1C6 = 9; R2C6 = 5
R8C5 = 9; R8C6 = 7
From here no problems can be expected...

Notes to V2V (VI)

V: Even Sandwich
I like to explore the possibilities that certain types offer. In the case of Even Sandwich there are some interesting steps during the solve that make it a lot easier to proceed, one of them very early in the process. Also: by knowing there is an even digit and no sandwiched digit in the respective row or column there must be odd digits two cells away from the even digit.
R5C3 = 2; 9 in row 4 in R4C45; R4C6 = 2; R4C4 = 9; R4C57 = {46}
R35C4 = {48}
3 in C5 in R23C5; R3C6 = 1; R1C4 = 5; 5 in C6 in R56C6; R6C5 = 7; R6C4 = 3
R1C36 = {68}; R1C2 = 9; 9 in R9 only in R9C3 :=> R9C4 = 2; R9C2 = 8; R9C6 = 7
R9C78 = {16}
1 in R8 in R8C3; R8C2 = 2; 7 in Block 7 in R8C1
R5C1 = 3; R46C1 = {19}
…

V2V: Sum Sandwich
Thinking about a variation to Even Sandwich, more ideas crossed my mind. I used two of those ideas for the Advent Calender at Logic Masters Germany, namely Consecutive Sandwich and Next to Nine. I thought the third idea would be suitable for this test: Sum Sandwich. I realised quite a lot of puzzles for the test were already on the hard side, so I decided to make this one very easy. The sums of 3 and 4 provide easy starts for this puzzle.

Notes to V2V (VII)

Here are the final notes to the test puzzles.
Please feel free to respond, ask more clarifications, point me to other solving strategies (or typo's).

1~9
Playing with sums in sudokus is one of my favourite habits. I really liked the idea of a ‘floating sum’ somewhere in the row/column immediately when I saw it once at a Sudoku Cup. Deriving information from the grid, limiting the positions of 1 and 9, it’s all in here.
R2C3 = 4; R2C4 = 9
In row 8 the digit outside the sum is 2 (33 +1+9=43), so: R8C1 = 2; R8C2 = 9; R8C9 = 9
Column 2: digits in R19C2 must be {68}
Column 4: since R8C4 <>1; R9C4 = 1; R1C4 = 6
Column 3: digits outside the sum add to 8; 1 or 2 cells. Since R89C3 <>1 and 9: R1C3 = 9; R7C3 = 1; R89C3 = {35}
…

Frame 1~9
I had little reservations towards this type. I am not too fond of sudokus with complicated rules and I was a bit afraid that the large number of clues outside the grid would be confusing.
I liked the fact that on one side you give more information about each row and column, but on the other side, by giving the clues in an increasing order, you take away information as well. So all in all, I gave it a go.
Important information: no zero outside the grid means no 1 or 9 in the first and last cell, and no neighbouring 1 and 9 as well.
Wheather people found all those outside clues confusing during solving or not I can’t tell, but it’s the puzzle with the highest percentage of correct entries.
R28C5 = {19}
R6C9 = 2; R5C9 = 1; R7C9 = 9; R9C8 = 1; R9C9 = 7; R8C9 = 3; R78C8 = {25}
R9C7 = 4; R8C7 = 6; R8C8 = 5; R7C8 = 2; R9C1 = 9
9 in R4 must go in R4C4; R4C13 = {78}
…

Hi Richard, thanks for the contest, nice Sudokus as expected. My performance felt like average for me, and had no luck too with the timing, missed the Sum Sandwich by maybe 30 seconds (but thats only 30 points). I felt I needed a break after the last contest, so I had some more or less puzzle-free weeks and no preparation, otherwise I think I would have felt "overpuzzled" in the upcoming WPF Grand Prix' and of course the German Championships. Now it's time to start training again ;-)

After solving the remaining half, I'm happy I didn't do the Greater than X. Nice path and my favourite in the set, but would have cost much too much time in the contest.

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

Enjoyed the test, albeit I had to do it in something of a rush. Thanks Richard!

How balanced do you think the puzzle types of this test were?	Perfectly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Way too many puzzles (too little time)
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

When I say "too little time" means I need much more to solve all puzzles. However, the contests shouldn't be any longer (I even would prefer shorter, but I understand that it is than more difficult to have a balanced choice of puzzles). So the time is really ok.

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Just right
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right

How balanced do you think the puzzle types of this test were?	Fairly balanced
What was your opinion of the distribution of easy/hard puzzles?	A bit hard
What did you think about the puzzle quality of the test?	Very nice
How did you feel about the length / time limit for this test?	Way too many puzzles (too little time)
Of the puzzles you solved/attempted, how well did their point values reflect the difficulty/time spent?	Most puzzles were worth the right amount
What was your opinion of the booklet formatting and printing?	Just right