Puzzle 034 – Unknown Shikaku

This is a 3.5-star Shikaku puzzle, with the Unknown twist. That is, some numbers have been replaced by question marks. Each question mark stands for a number other than zero.

034 - Unknown Shikaku

There, a new puzzle. Guess the theme. Hint: Convert the numbers to letters.

As I said in Puzzle 033, I will post more Unknown puzzles. This is one of them.

Tomorrow I will be back to school. That means, wasted time at schoolΒ will might be used to make puzzles.

However, I also have some bad news. In September, I have a math competition that is very important to me, so I need to study/learn/practice more often. This means I might not be able to update this blog at the same rate as before. Moreover, at 11th grade, things start to get serious; I might need to dedicate more time to school. So…sorry for the inconvenience due to the irregularity of my (upcoming) schedule.

Posted in Deduction Puzzles, Shikaku, Unknown, [Extra Variations] | Leave a comment

Special Puzzle 004 – Abstract Exact Cover

Inspired from this Wikipedia article.

Choose some sets such that the intersection between any two of the sets is an empty set and the union of them is {1, 2, …, 10}. In other (less mathematical) words, choose some groups so each number from 1 to 10 appears exactly once among the chosen groups.

A = {2, 6, 7, 9}
B = {1, 2, 4, 6}
C = {1, 3, 5, 8}
D = {3, 5, 6, 10}
E = {2, 7, 9, 10}
F = {4, 8, 9}
G = {4, 10}

Posted in Abstract, Deduction Puzzles | 6 Comments

J-tris Puzzle

EDIT: Some things.

Yeah, sorry for the lack of update. I have various things to do. Including making this.

I know you like puzzles that are more towards Sudoku family (logical, deductive, unique solution, etc), and not necessarily Sokoban family (not-really-logical, non-unique solution, usually record-based, etc), but I inform you of the thing that I’m making that I suspend the updates to this blog: J-tris Puzzle.

J-tris Puzzle is a puzzle game inspired from Tetris. The matrix is smaller, to allow more strategy. Clean up the blocks in a puzzle to complete that puzzle. Do it in the minimum possible moves and compete with the whole world to be the record holder!

It’s v1.1.0b. Even after the launch version, I still need comments/suggestions/feedback from as many people as possible; that’s why I post this. Later, I might actually post a “true advertisement” of J-tris Puzzle.

And for some final words for this post, this blog will feature both deduction puzzles (nikoli-style like Sudoku etc) and optimization puzzles (like Sokoban, J-tris Puzzle above, etc). Though the latter one will appear much, much less often.

Posted in Optimization Puzzles | Leave a comment

Puzzle 033 – Puzzle Collection

This is a Puzzle Collection. That is, this puzzle contains a lot of small puzzles. The first three puzzles are Shikaku puzzles; the third one has an Unknown twist. The next three puzzles are Fillomino puzzles. The next three puzzles are Hebi-Ichigo puzzles; the third one has an Unknown twist. The last puzzle is a Block Puzzle puzzle. The Unknown twist is that a question mark only indicates that it is a given cell, but the number is unknown (but not zero).

The difficulties for each puzzle is the following:

  • Left Shikaku: 1.0-star
  • Middle Shikaku: 3.0-star
  • Right Unknown Shikaku: 2.0-star
  • Left Fillomino: 2.5-star
  • Middle Fillomino: 2.5-star
  • Right Fillomino: 1.0-star
  • Left Hebi-Ichigo: 1.5-star
  • Middle Hebi-Ichigo: 2.0-star
  • Right Unknown Hebi-Ichigo: 2.5-star
  • Block Puzzle: 1.5-star

Ignore the light shadings in some puzzles.

033 - Puzzle Collection

First of all, sorry for the very late update. I have some business for the last few days…very busy that I can’t make too much puzzles. I think I won’t update this blog too often in this summer holiday. (You know, I make the puzzles when I have free time at school. πŸ˜› ) Moreover, I even failed to match the deadline I set myself five days ago that I will finish it at Tuesday.

For that reason, I present this batch of ten puzzles. I tried to make some different things, and see what happened… For all except Hebi-Ichigo, for each (light-)shaded cell, shade all cells which are in the same region with that cell. For Hebi-Ichigo, simply shade all cells which belong to the snake. See what happens, and you might probably know why this blog’s address is chaoticiak492 and not any other number… For that reason, this puzzle batch is a difficult thing to create (though probably very easy to solve).

Some comments on the puzzles (counting the Shikaku puzzles 1-3, Fillomino puzzles 4-6, Hebi-Ichigo puzzles 7-9, and Block Puzzle puzzle 10)…

1: It is very easy. VERY easy. But making it is quite a difficulty, with the designed theme.
2: Hey, I just realized that that puzzle has only 3s and 4s! It’s funny. And now it’s the most difficult puzzle after difficulty edits. Wow.
3: Yep, all except three givens are question marks. Down-rated to 2.0 stars…
4: Should be quite standard with a technique used repeatedly.
5: A Nurikabe-like technique is used once here. That is, if you solve it in the same way as mine.
6: Very basic. The only puzzle with vertical symmetry.
7: First Hebi-Ichigo constructed. Before solving any. And with the very constrained theme, this is quite a challenge for me, but apparently it succeeded to be this puzzle with a horizontal symmetry.
8: Like 7. Some funny approach that I never encountered in the puzzles I have ever solved exist here.
9: Large blank area. Guess how many snakes are in the puzzle.
10: First Block Puzzle constructed. Yeah, before solving any either. I had a very difficult time to decide which puzzle genre will I use in this final puzzle, before finally go with Block Puzzle.

That wraps this batch of ten puzzles. I challenge you to solve them all in under three minutes, just like a normal 10×10 puzzle will usually take to solve.

Next, I think I will have some small puzzles with the Unknown twist, or some medium/large puzzles like usual (no twist). Just stay tuned.

Posted in Block Puzzle, Deduction Puzzles, Fillomino, Fillomino (Family), Hebi-Ichigo, Shikaku, Unknown, [Extra Variations] | 4 Comments

Puzzle 032 – Tapa

This is a 2.5-star Tapa puzzle.


032 - Tapa

And there we have a new puzzle type, along with the completion of another of my self-assigned task of posting Puzzle 032 before or at Sunday this week.

A nicely made puzzle, if I must say to myself. The 1-8 clues around the grid, along with the all double-clue in the middle ring, and the question marks in the middlemost, display a (fairly) good artistic design. And solving it is quite fun, though quite easy. (Remember that I say this to myself, so I might be biased. πŸ˜› )

Posted in Deduction Puzzles, Tapa | Leave a comment

Puzzle 031 – Warp Fillomino

This is a 4.5-star Warp Fillomino puzzle; that is, a Fillomino puzzle with a Warp twist. Any edge that is not black are connected with another edge, either directly (as in usual grid) or by warping (as indicated by the lines). (Click the image to enlarge it.)

031 - Warp Fillomino

If you don’t get how the warp works, let’s get an example; R5C1 (the cell above the leftmost 3) is adjacent to R5C2 to the right, R6C1 to the bottom, R5C16 (the 6) by warping to the left, and R1C12 (the cell above the topmost 1).

And this blog officially enters the third dimension!

Inspired from making a funny but still enjoyable figure, I decided to make a cube-shaped Fillomino. And there we have it. Since symmetry doesn’t work nicely here, I decided to do something else: when you fold the cube, every pair of opposing sides have their numbers stacked on each other.

Good luck solving this one. You might want to get some real 4x4x4 cube and solve this puzzle on it. If you do, beware of copying; you must copy them correctly or you will have a trouble. πŸ™‚ And if you solve this in 2D, beware of counting the sizes correctly and to get each cell’s neighbors correctly. No one said that it’s impossible to solve this on other instruments; mathgrant said that he solved this with MS Paint.

I might have some more Warp-twist puzzles later, stay with me. πŸ™‚

Posted in Deduction Puzzles, Fillomino, Fillomino (Family), Warp, [Extra Variations] | 2 Comments

Special Puzzle 003 – Unknown Nurikabe II

This is a 1.5-star Unknown Nurikabe II; that is, a Nurikabe II puzzle with the Unknown twist. Some objects have less meaning than it should be. In this puzzle, one given is not placed, and it’s value is unknown. It’s up to you to determine where the given would be placed, and what value it should be. The solution is not necessarily unique...or is it?

S003 - Nurikabe II (Hidden)

Whoa?! An unknown clue in Nurikabe?! What could that be? And why the rating is only 1.5 stars? Something is suspicious here…

Posted in Deduction Puzzles, Nurikabe (Family), Nurikabe II, Unknown, [Extra Variations] | 5 Comments

Puzzle 030 – Hidato

This is a 3.5-star Hidato puzzle.

There are 62 white cells in this puzzle.

030 - Hidato

Edit as of 2011/06/09: Fixed multiple solutions.

This man is hanged because he didn’t manage to guess the three-letter word. You will also be hanged by not completing this puzzle. Just kidding.

This puzzle is quite a little difficult. Black cells are very effective to force some paths. And do you expect the 62 to be there instead of anywhere else that seems more “obvious”? πŸ˜›

Posted in Deduction Puzzles, Hidato | 4 Comments

Special Puzzle 002 – Multitype

This is a 1.5-star puzzle. However, the puzzle genre is unknown…read on.

S002 - Multitype

There are at least three puzzle types on which this grid has a unique solution using their respective rules. Guess the three puzzle types first, but highlight this paragraph if you give up. The puzzle types on which I found this grid has a unique solution using their respective rules are Slitherlink, Fillomino, and Latin Squares.

These are extremely easy. I thought of this while I don’t have access to my computer or my puzzle book. However, this puzzle shows the ability of combining various puzzle types into one.

And the reason of giving this 1.5 stars? It’s three puzzles of 0.5 stars each. Just add ’em up! πŸ˜›

Posted in Deduction Puzzles, Fillomino, Fillomino (Family), Slitherlink, Slitherlink (Family), Sudoku (Family) | 2 Comments


I want to know you, my readers, and what do you think about the puzzles posted in this blog so far. Please allocate about five minutes to answer this survey, either by comment or e-mail.


  1. Do you often check my blog (or subscribe to my blog)?
  2. How do you know this blog?
  3. What do you think I should do to get more readers to this blog?


  1. Do you think the puzzles should be harder? Easier? Or even more variety of difficulty?
  2. Do you think I should allocate more to either symmetry and pattern or difficulty? Or are they okay?
  3. Are you more interested in some puzzle type(s) (and want me to make more)? Are you less interested in some puzzle type(s) (and want me to make less)? Are you interested on seeing some puzzle type(s) in this blog that this blog hasn’t had?


  1. Do you think I should post more frequently?
  2. Do you think I should post more regularly?
  3. Do you think my descriptions of the puzzle types need improvement?

Thank you for reading my blog and answering the above survey.

Posted in Non-Puzzles | 6 Comments