22 days to restore the colours


Welcome to Colour Restore!
For the first time ever, you will get a glimpse at what happens when colours are introduced to logic puzzles! Colour Restore will feature 8 vibrant puzzles!

Don’t get too excited just now, the creator is yet to be convinced that we are ready for coloured-puzzles. So you will have to please him first. The first 3 puzzles will still be the old-fashioned black and white shading puzzles.

After that… see for yourself!

The prize for the winner is the 2014 Mindbenders and Brainteasers Calendar from Workman Publishing. A great new year’s gift for any puzzler!

Click at the “About” page to see more details at how colour puzzles work. This event will last 22 days, one week earlier than my usual events. This is solely because the prize is a puzzle calendar and it is best received before 2014. I hope you enjoy this event as much as I enjoyed making it.

One further reminder, I ran a poll asking for puzzle suggestions for a future event.
[Edit: 12/12/2013 – Poll Closed]

This poll closes in less than 2 weeks, you can pick up to 5 puzzles. I am thankful for all votes thus far, keep them coming!

Bring in the colour pencils!

Ever wondered why our puzzles are in black and white?

Before the dawn of human logicsmiths, our puzzles were actually in colour. Then one day, the creator decided the world isn’t ready to handle the chromatic effects it would bring. So he grabbed a huge cloth and wiped the colours away…


Explore a whole new dimension when puzzles are splashed with colours.

Coming soon

Ending 2013

2013 is nearly over.

For the past month I’ve been fighting with Sony about my broken laptop. All my puzzle files are there, it is certain that there is no hope of getting them back. I backup my files regularly so I’ll have to wait and see how much is actually missing.

The WSC/WPC ended a long while ago but I just got my report up. I wrote some of it while in China, when my mind was still fresh, so the slightest details are there. You can see the Semifinals and Finals coverage below. I still have some photos left so those will be sprinkled in the preliminaries excerpt, which I’ll eventually get around to do.

Now onto the events. One event is planned before the end of 2013.
Also, Nikoli Hurdles 2 will be held early 2014. You can find the results of the first edition here.
Some Nikoli puzzles are obviously more popular than others. Nikoli Hurdles 2 will feature more obscure types.
In fact, I haven’t even written any familiar types for Nikoli Hurdles 2!

As much fun as it sounds but that won’t be good for newcomers. I have no idea what common Nikoli type people like these days. Perhaps, you can help me. Below are 12 types that come up a lot in the world wide web. I’ve omitted Nurikabe, Numberlink and Yajilin because they already appeared in Nikoli Hurdles 1. Please tick the types you personally like, you can choose up to 5 answers.
Oh and no one gets to see the results just yet. Poll closes in one month from now.

I appreciate your votes. Thank you!

[Edit: 12/12/2013 – Poll Closed]

WSC Semifinals + Finals Coverage


Half the room was taped off by two large screens separating the semi-finalists and the audience. China is a great host with access to a lot of high tech gadgets: fancy cameras, professional lightings and what have you but unfortunately they had Mickey Mouse running them.

Instead of close action of speed solvers we got something like one screen showing a reflection of the audience while the fire of the semis was ever blazing. Most the time you also wonder why would we be interested in looking at an extreme close-up of Jakub’s pencil case or Jan Novotny’s hat? Show us the puzzles!!

Two screens were erected for the audience

Two screens were erected for the audience

Eventually we did get ‘some’ action. By ‘some’ I meant a shuffling of close-ups from a random competitor’s progress. Even when that competitor is in last place – far from the heat of the competition.

Here’s a rough run down:
The preliminaries were dominated by Tiit Vunk who was rewarded with about an 8 minute head start over Bastien. After every three puzzles, the field is trimmed down by 2-3 players.

The first puzzle was a classic, I think Tiit finished it before anyone else even started. The second puzzle was a Killer sudoku, which provided a break for the rest of the field as neither Tiit nor Bastien seem to have made any progress on it. Also: Tiit uses twink! (In America, you might know it as “white-out”). Pen/twink in the semi-finals!?

Killer Sudoku that stumped Tiit and Bastien

Killer Sudoku that stumped Tiit and Bastien

The third puzzle was an Anti-diagonal sudoku. The first seven solvers to cross this mark proceeds, eliminating the last three. Jan (M) and Kota emerged from the field and were the first to move onto the second phase.
One by one, the rest of the field took a vacant spot, leaving the top 2 seeds Tiit and Bastien eliminated in the first bout! Hideaki took the last spot and 10th place Jan Novotny couldn’t make up for his handicap.

The 4th puzzle, another classic, was followed by Antiknight sudoku. Jan and Kota were closely followed by Jin Ce. At this point, Jakub (with crutches) lagged behind and was on the verge of being eliminated with Hideaki. The real shuffling was done by the 6th puzzle – Product Star sudoku. This really impeded Jan and produced a new leader in Jin Ce.

Kota and Jin Ce were first to the second checkpoint. China’s young star Sun Cheran (can anyone make me feel worse about my solving ability by telling me how old she is?), passed Jan at this point and joined Jin Ce in chasing Kota. Jakub somehow made up for his lost time and was literally limping to secure a spot in the top 5. Jan eventually finished and eliminated Hideaki and Seungjae.

And we're down to five

And we’re down to five

The 7th puzzle was a third classic sudoku which didn’t produce any drama, unlike the 8th puzzle – a scary-looking Irregular Sudoku.
Kota had about a minute lead over Jin Ce going into this puzzle, but he made quick work and left for the final puzzle – Pyramid Sudoku (an extra-regions sudoku with a different name).

So it was Kota leading by a slight margin with two young Chinese solvers breathing down the back of his neck. When things got really close, disaster struck one of the two pursuers — Sun Cheran erased her entire Irregular sudoku puzzle.

The audience gasped as Sun Cheran erases her entire Irregular Sudoku

The audience gasped as Sun Cheran erases her entire Irregular Sudoku

This window of opportunity provided Jakub with a much-needed break as he quickly passes Sun. The audience held their breaths to see whether it was Kota or Jin who would be the first to submit. A wild applause broke when it was Kota who secured the first ticket to the finals.

Kota taking a well-deserved drink after securing the first spot in the finals

Kota taking a well-deserved drink after securing the first spot in the finals

Another moment of suspense to see if Jakub would be able to pass Jin. About a minute later, Jin raised his hand – during the one minute verification period Jakub submitted! Jin’s 30 second lead kicked Jakub out of the finals.

Jin takes the last spot to the finals

Jin takes the last spot to the finals


The final showdown was a best of five match done on giant boards for all to see. I assume this was televised since the emcee looked more formal than usual and speaking in Chinese before translating himself in English.

Puzzle 1 – Hard Classic won by Kota.

Puzzle 2 – Easy Classic won by Jin.

The match was tied 1-1. It was funny looking at Kota performing some sort of tennis manoeuvre and cheekily smiling every time he lost. He did this again after the third puzzle.


Kota VS. Jin on stage

Puzzle 3 – Consecutive Sudoku won by Jin.
When puzzle 3 began, Kota immediately shoved a run of 1-2-3-4 into the grid. Me and Sinchai were astonished at how the deduction was done. About a minute in, Kota erased them and we realized he was just bifurcating – probably a logical approach given the speedy format of the play-offs.
Jin takes the lead 1-2.

Puzzle 4 – Ratio Sudoku won by Kota.
A nail-biter. Kota needs to win to force a 5th puzzle. And he delivered.

Final Puzzle – Medium Classic.
Interesting to see all the Classics being selected in the finals. Everyone knows that Chinese players produce stunning results in the Classics, I thought Kota would’ve chosen some weird variants to drag Jin out of his comfort zone. This final puzzle was pure excitement to the last cell.
We saw Jin filling in his last square and raising his hand only to turn our eyes to Kota doing his tennis swing in thin air. What does that mean? The gap separating them was only about 3 seconds!

I can’t help but think that the crowd was cheering on Kota. The post-competition atmosphere wasn’t as lively as I anticipated. Is it because the winner being from the host nation raises eyebrows?

A full reception witnessing the finals

A full reception witnessing the finals

Kota, clearly with energy left, gathered a small crowd when he joined a group of Nikoli members race-solving Kakuro. I’m not too bad at Kakuro myself, yet I didn’t have enough audacity to challenge anyone there at that time. Hope to see everyone at future World Kaku- er, I mean World Sudoku Championships again soon.

World Kakuro Championship?

World Kakuro Championship?