Medusa has arrived


Argus Panoptes has been defeated!
In just over a week, 31 solvers defeated Argus Panoptes. Here is the list of solvers in order of their submission times:

  1. Yuhei Kusui
  2. Ivan Koswara
  3. Alex Pei
  4. Ken Levine
  5. Prasanna Seshadri
  6. Zbigniew Laskowski
  7. Antonis Lalatsas
  8. Nick Brady
  9. Robert Vollmert
  10. Andrew Brecher
  11. Walker Anderson
  12. Jakub Hrazdira
  13. Edison He
  14. Matt Lahut
  15. Alan O’Donnell
  16. Tom Collyer
  17. Michael Deluca
  18. Thomas Powell
  19. Jack Bross
  20. Willy Petrenko
  21. Maja Gribajcevic
  22. Giovanni Pagano
  23. Stefan Tomlins
  24. Logan Dymond
  25. Branko Ceranic
  26. Matej Uher
  27. Nikola Zivanovic
  28. Andrey Bogdanov
  29. Neil Zussman
  30. John Reid
  31. James McGowan

The giant Masyu seemed to be really easy in comparison to Hydra’s Tapa two weeks ago. Fret not!
You will spend the next 8 days surviving in Medusa’s Snake Pit!
Can you slither your way to victory? Get the puzzle at the menu above.
There are a lot of rules to swallow in this one, so if you’re unsure about the instructions, feel free to leave a comment and I’ll get back to you as soon as possible.


Kota retains BRANDS Sudoku title

The 2014 BRANDS Thailand Sudoku Open concluded today. The usual 2-day format was increased by one day since in Thailand; it’s a 4-day weekend. The tournament started on Friday and the venue shifted from Siam Paragon to Central Ladprao, both are department stores in Bangkok.

Three to a table in the middle of a department store? Come on.  [Photo: Thailand Crossword Association]

Three to a table in the middle of a department store? Come on.
[Photo: Thailand Crossword Association]

From what I see, the conditions were awful. The instruction booklet was very sloppy and an unhealthy fraction of the puzzles were clearly computer-generated. Really the only thing this event is still attracting both local stars and international participants is the money. The winner gets to pocket a nice $5000 US.

This year saw an all-time low of international names. Just Jan and Kota returned. Yuhei was busy and the entire Indian team had to cancel their visit because the dates clashed with their hastily-organized Times Championship. Last year’s finalists Farhan Hassin (Malaysia) and Tung Yi Wu (Taiwan) were also absent. My friend, Gabriel Gan (Singapore) usually turns up as with a handful of Chinese players but none came this year. The only country to consistently field in a team every year is the Philippines. But ever since variants start to make more appearance than classic sudokus, none of them managed to leave any impressive results for the last 6 years.

Poramet didn't actually turn up. [Photo: Thailand Crossword Association]

Two funny things: 1. The logo has been re-used for the last 4 years (note “2011″) and 2. Poramet didn’t even sign up.
[Photo: Thailand Crossword Association]

Let alone solvers from overseas, Thailand fielded an even less impressive roster. Only two members of our national team turned up. Sinchai Rungsangrattanakul, who recently entered to world’s top 10, was our nation’s favourite. College had me and Poramet occupied for the weekend so only rising star Supachai Thongsawang join Sinchai as our front-runners.

Given the many absences, the final five was somewhat predictable. Sinchai collected the most points in the preliminaries so he earned the stage’s centre. Sandwiching him was Jan and Takuya Sugimoto, a newcomer to the event. Kota was placed 4th and I understood there was a tight race for the last spot which was narrowly won by Supachai.

Close race a spot in the finals. [Photo: Thananon Boonkrong]

Close race for a spot in the finals.
[Photo: Thananon Boonkrong]

The finals must have been a nail-biter as Kota became the first person in this event’s 8-year history to successfully defend his title. Jan finished second again and the revelation of the tournament goes to 18-year old Supachai who squeezed out a third place win.

Finals on stage [Photo: Thananon Boonkrong]

Finalists on stage from left to right: Kota, Jan, Sinchai, Takuya and Supachai
[Photo: Thananon Boonkrong]

Here is the puzzle that was used in the finals. Print out a large copy and try solving it standing up on a wonky board to get the real simulation of the finals.

Final puzzle [Photo: Supachai Thongsawang]

Final puzzle
[Photo: Supachai Thongsawang]

You can compare your times with the finalists, here:
#1: Kota Morinishi (JPN) 8.43
#2: Jan Mrozowski (POL) 11.39
#3: Supachai Thongsawang (THA) 12.13
#4: Takuya Sugimoto (JPN) 14.03
#5: Sinchai Rungsangrattanakul (THA) 20.00 – DNF

I would love to welcome international solvers to this event, but I still think there are too many things this tournament can improve on. Our national association is not very energetic at addressing them so do come along but don’t expect the best hospitality cause you’ll probably be disappointed. Lastly, can I ask again who wrote the few handmade puzzles for this event? A lot of people want to know who our national association has ties with and why they are making it so secretive.

Hydra defeated, Argus appears


Entries for Hydra have now been closed. When you submit an answer I will normally take no more than 3 days to reply. I have replied to every submission I’ve received so if you think you’ve entered and haven’t heard from me yet, contact me immediately.

As for Hydra, 23 warriors took a shot in the last 8 days. I asked for the number of black squares in the central Tapa, the correct answer to Hydra was 35.
Here is the list of solvers in the order of submission:

  1. Edison He
  2. James McGowan
  3. Prasanna Seshadri
  4. Andrey Bogdanov
  5. Antonis Lalatsas
  6. Jack Bross*
  7. Serkan Yurekli
  8. Alex Pei
  9. Ivan Koswara
  10. Andrew Brecher
  11. Nick Brady*
  12. Nikola Zivanovic
  13. Tamas Antal
  14. Ken Levine
  15. Stefan Tomlins
  16. Willy Petrenko
  17. Yuhei Kusui
  18. Matt Lahut
  19. Michael Deluca
  20. Jakub Hrazdira
  21. Thomas Powell
  22. Robert Vollmert
  23. John Reid

*Alas! Hydra claimed two victims!
Jack and Nick (both submitted 34 and were one cell off from the right answer) will have to be excluded from the tournament bracket. Sorry! Try again!

As for the remaining 21, I won’t reveal the results just yet. You’ll have to be patient. Why not increase your odds of winning by slaying a few more giants?

Argus Panoptes is now the current giant on this blog, he is a lot tamer than Hydra. Click on his name at the menu above to see what you’re up against this week. You have until the 18th July to solve the puzzle before Medusa arrives.

Have fun!

Four giants approaching!



Throughout July Giants 2014, one monster of a puzzle will be released every 8 days. There will be 4 puzzles in total. You have 8 days to solve each puzzle before the monster departs and the next monster appears.

One winner is selected from each monster and they will face each other at the end to determine one winner.

The monsters appearing are:
1. Hydra [3rd July-10th July]
2. Argus Panoptes [11th July-18th July]
3. Medusa [19th July-26th July]
4. Cerberus [27th July-3rd August]

The puzzles and further details and be found in the menu above.
Without further ado, here comes Hydra, a nine-headed Mastermind Tapa puzzle!

Solutions to Anchors Aweigh – 4/4

Puzzle 6 – Double Battleships

I first saw this type at the 2013 WPC in Thomas Snyder’s round. The puzzle above was easily the hardest out of all the puzzles in Anchors Aweigh, to which solver James McGowan rightly agrees: trying to keep track of what’s happening in each cell. I did it in MSPaint, so had 6 colours in action.

The reason this last part of the solutions took so long was that I intended to write up a full solving guideline. As much as I wanted to do so, my study timetable disagreed, so we will have to just make do for now. My starting point was at the 4th column with 5 and 3 adding up to 8 (leaving two cells blank). I remembered vaguely how the puzzle solves from left to right but since a couple of months has elapsed, I have very little memory about it.


Puzzle 7 – Classic Battleships (Hard)


Despite the label, I don’t think this puzzle was that difficult at all. You have to try out horizontal/vertical orientations of the long ships to get through the first part of the puzzle.
Then you should have a few ships left at the end to satisfy the two 3s in the 9th and 10th row.

And that’s all the puzzles covered in Anchors Aweigh. Thomas, Antonis and Walker had all received their prizes.
Want to be the next winner?
Well, I’ve already cooked up more puzzles for future events and it looks promising from here.
Come back in a few days for…



I got my regular dose of Nikoli Puzzle Communication books last night. Last year I complained to myself about the repetitive nature of their puzzles that slowly bored me overtime, I stopped my subscription to their online puzzles and stuck to their magazines instead.

What I look forward to in each Nikoli Puzzle Communication is everything but the pages stuffed to the gills with your usual Masyu, Slitherlink, Fillomino and what not. I only solve them on auto-pilot cause most of the time, those puzzles aren’t memorable. They had to be darn impressive to even warrant a grin.

Sometimes I raise a few eyebrows at how constructors manage to pull off beautiful givens in their puzzles. And that’s it. But the latest issue, No.147, had one page that made my eyes pop out.


Shimacharo managed to shove an entire Sudoku into this beast of a Ripple Effect puzzle!! Imagine how long that took!
I eagerly wait for the day when our puzzle community is large enough to have more magazines like Nikoli’s.

If you want your share of Nikoli’s goodies, hover all the way down to the links below where I’ve linked Nikoli’s website since the beginning of this blog. Another hard way to get Nikoli magazines is to win my next event which will start next month. More about that soon.

Long live Nikoli!

Solutions to Anchors Aweigh – 3/4

 Puzzle 4 – Battleship Sudoku

puz5dokuInvented by Thomas Snyder, Battleship Sudoku was one of the early puzzle types I discovered a few years back. The givens in this puzzle form an anchor which was later asked as the final question at Yubotu Island.

As with most Battleships, you start by locating the longest ship, here it is the 6587-battleship. Scanning column to column, row to row, you can see that there is only one available row for the Battleship. Conveniently, only one exact location.

aapuz5ansaThe next step is to look at the 8th column. There are 4 vacant squares for three ships. If the lone cell (R7C8, shaded red in the diagram below) is occupied, it will eliminate 2 cells in the 6th row which will force all 4 remaining cells to be occupied.Should this happen, the 4th column cannot take 3 ship parts (it can only take 2), so we can deduce that R7C8 will be empty, and that the 3 remaining cells of the 8th column will be occupied by a 3-cell long destroyer.

aapuz5ansbFrom here several ships force itself into the grid.

aapuz5anscThe last part of the puzzle is fitting the three submarines into the upper-left portion of the puzzle and all is done!



National Qualifiers

With college workload increasing, things are going to slow down from here. Two final parts of Anchors Aweigh solutions are still to come. In the meantime, why not check out some national championship puzzles recently? I use to enjoy comparing my results to other countries’ qualifying scores to see if I’d make the team if I was an official participant. With the WSC/WPC looming near, several countries are already forming their teams using online tests.


USSC and USPC were the first to finish. The USSC looked a bit incomplete without Thomas Snyder writing his share of puzzles with Wei-Hwa Huang. The lack of notifications certainly didn’t help increase the number of participants either. On the other hand, the USPC is like a yearly tradition for me and having to sit out this year was a shame. As always, the puzzles are top-notch and I am looking forward to solve them later.

UKSC and UKPC followed trend a week later. UKSC is already finished but nothing’s stopping you from trying out the puzzles if you haven’t done so. Tom Collyer’s sudokus are usually clean, fair difficulty level and visually-appealing, which is just how I like sudokus. The UKPC started yesterday and will end on Monday. I have the vibe that UKPC looks better and better every year. And yes, I’m being bias because some of my puzzles are in it :)
You can see three of my puzzles mixed in with other great puzzles so dive in and see if you can beat Neil Zussman.

JNPC and JPC took place just a few hours ago. I remembered digging for Tetsuya Nishio Cup Number Place Championship (or something like that) and enjoyed it so much that I had to reprint the whole lot and redo it. The puzzles are bound to be awesome. Some Japanese puzzle fans generously translated these contests for us since last year so the JPC won’t be an instructionless test for foreigners anymore. Too bad the contest didn’t open for the whole weekend unlike…

IPC and ISC. The puzzle test takes place right now as I’m typing this and will open for 2 more days. The ISC will be on next weekend. I like the way LMI standardized the IPC/ISC sets throughout the years. You get a certain puzzle type and one of its variants to solve in 150 minutes. I also like the first puzzle of the IPC each year. It’s usually some fun match-ups or short puzzle questions you don’t see often in normal online tests. I’ve never took part in IPC/ISC because somehow each year I won’t have access to a printer during that particular weekend. This is 2014 and history is repeating itself. I guess I’ll compare my performance afterwards.

Back to my blog.
This morning I received a parcel in the mail.


Extra copies of Battleship Sudoku had just arrived!
I’ll be mailing this off to the 3 lucky winners of Anchors Aweigh as soon as I can.
Want to be as lucky as they are?
Well, you’ll have to enter!
Currently, I have new events drawn up for July and October. If my productivity improves maybe I’ll start early. Check this space for more announcements, or even better, subscribe to my blog updates to ensure you will not miss an event!

Solutions to Anchors Aweigh – 2/4

Puzzle 3 – Hexagon Battleships

This is the first time I tried constructing puzzles on a hexagonal grid. I Googled some hexagonal grid paper and printed them out just for the occasion. I made several Hexagon Battleships and all they turned out to be too difficult. I find that this one (which isn’t that easy either) was the most suitable. The intended opening was the 3 crossing the 1. You will find the right cell that needs to be omitted from housing a ship.

Fascinatingly, the large Battleship doesn’t come in play until half way through the puzzle.


Puzzle 4 – Classic Battleships (medium)

First of all, let’s begin filling in the obvious:


One destroyer and several ship segments (blue cells) are already discovered. It is useful to know that in a standard set of Battleships, 20 cells are used. The bottom clues add up to 15 (6+5+4), so only 5 cells that are not in those 3 columns can afford to hold a ship. You can see that 4 out of those 5 are already found which means only one cell in the 7 remaining columns contains a ship.

The next step here is a little tricky. Look at the “3” clue (the top one). You can no longer put 3 ship parts in the 3 clued columns – this means at least one ship-containing cell will belong somewhere in the remaining 7 columns. If you noticed this, you can eliminate all remaining unclued rows that do not overlap the 3 clued columns.


Wow! Now that’s a short cut! You now fill the remaining ships in like the commanding captain you are!


Solutions to Anchors Aweigh – 1/4

fleetaaPuzzle 1 – Classic Battleships [Easy]puz1clase Anchors Aweigh included 3 classics. The first classic is straightforward and shouldn’t pose any significant problems. All deductions were easy. Almost everything was forced. The Battleship and two submarines were left in the end. These only fit one way at the bottom right quadrant of the grid. aapuz1ansPuzzle 2 – Chess Battleshipspuz2mate In all Chess Battleships, the deduction usually starts at the King. All four corners of the King must be used by different ships, so you can cross out the four cells that are adjacent to the King. aapuz2ansaIn this particular puzzle, there are two possible locations for the Battleship where every piece can attack it. If you tried the blue location, you will notice that the Knight will not be able to attack 4 ships. So we can be certain that the Battleship has to be at the orange position. aapuz2ansb In the diagram above, “?” represent cells that will be occupied by a ship. The green cells are attacked by the Knight, and the Bishop attacks the remaining blue cells. Working with long ships, we now locate the 2 cruisers. One cruiser will be near the King, away from the Rook. So the remaining cruiser will have to be looming near the Rook. The next thing to note is that none of the green cells will be attacked by the Rook. This means the cruiser that the Knight attacks will be shared with the King, incidentally there is only one spot for that. aapuz2anscThe remaining cruiser has to be attacked by three remaining pieces; Queen, Rook and Bishop. Again, only one position that meets all the criteria. At this point, keep tracker of the Rook and Queen’s directions. They must attack only four ships. The Rook has to attack a ship at all sides. The Queen already strikes twice diagonally and twice vertically so there shouldn’t be any ships horizontal to the Queen. You can determine one destroyer right away where it is attacked by the Bishop and King. The remaining corner of the King has to be a submarine. Now the remaining ships shouldn’t be too hard to fiddle in. aapuz2ansd