Puzzle #9

This is a Masyu puzzle.



Difficulty: trivial

Theme: Diagonal... Symmetry?!


Alright, so I took my Shindanmaker result a little too literally with "must have one line of symmetry". But it never said the line of symmetry had to go through the centre!

An alternate theme name I could have gone with is "Mostly-White Spade". But I think this current theme stands out best. :P

Puzzle #8

This is a Masyu puzzle.



Difficulty: trivial

Theme: Diagonal Antisymmetry


What's this? A simple Masyu puzzle for my first post in ages? Yes.

On Twitter right now, a few Japanese puzzlemakers are using a Shindanmaker to decide what puzzles to create. My task was to create an 8-by-8 Masyu that had givens with linear symmetry. Naturally, I decided to make one with antisymmetry because antisymmetric Masyus are considered beautiful.

And of course, I forgot about the size of the grid when making it. And it also turned out way easier than I'd have liked it. Ugh.

Oh well, I'm still posting it here for content because I still think it's a nice theme. Thanks go to mathgrant for helping me place a pair of givens to give a unique solution when I thought I'd run into something unfixable.

Hmm, the word "run" in "I thought I'd run into" could be in either past perfect tense or present conditional tense. Interesting.

Anyway, I think I'll post the 8x8 Masyu if I construct it. Which I hopefully will.

Hunt Puzzle #1

This is not a logic puzzle. Yes, I've jumped the shark (just for this one post). The final answer is a single word.

Difficulty: Medium

Theme: Anything Puzzler Media can do, I can do better!

PDF download here.


  • A cure, mixed for a rocket
  • Accidental smart
  • Add two to ice container
  • Against a part of a poem
  • Aged eccentric's exclamation
  • An algebra falsehood
  • Attempt street meeting
  • Be angry with half of triangle
  • Be next to one; however...
  • Copper search going from 2 to 8
  • Crossdresser's "opposite part"
  • Detailed tree confusion
  • Endlessly diddled about!
  • Endlessly walk through water glob
  • Erodes alternative pass
  • Even Seymour's bird
  • Fail a second time? Careless!
  • Grace, confused, entering A&E area
  • Hash mag'd ENE e.g. KPvK
  • Healing and processing, I calmed
  • Hostile leaders of Iraq, Cambodia, and Yemen
  • Imaginary friend put Al in distress
  • Includes irritated dads
  • Lunatic's ole' cat
  • Make a mistake and boo Caesar
  • Middle-Eastern whaling ship captain switches out head of harpoon, for reals
  • Parasite digested leaf
  • Pee jumps back; strange
  • Planning and including partner
  • Pod #12 rots sandwich
  • Rear's after front part
  • Recited poetry overdue
  • Recruit's partially tan
  • River cove opens up beginnings
  • Ruth et al.'s sample letter
  • Scientist's endless test lab
  • Skins masks
  • Sledge-hammered windowsills
  • Soaked tweeds, ruined
  • Study at regional advisory headquarters
  • Uzi 'n' cannon to hide copper's partner for battery
  • Walked around setter in street
  • Weasley character goes back to a gate
  • Wheeze in big aspen 
  • Whole-some, I hear
  • Without sex, start to cum with speed
  • Wrecks head half and tail of common bird

Exams are coming up in a month, so expect what little output there is now to dwindle. Hopefully I can get back to making more puzzles afterwards (but don't count on it).

Puzzle #7

This is a Deformable Total Masyu puzzle, a variant of Masyu. In addition to the rules of Masyu, all possible circles have been given; i.e. it is not possible to add any more circles to the grid so that it is consistent with the solution. Further, any white circle may instead behave as a black circle.



Difficulty: Evil Zinger

Theme: The most evil Deformable Total Masyu ever!

Puz-PRE link. (Note: Puz-PRE has neither the "total" nor "deformable" constraints programmed in. The solver may incorrectly mark incorrect answers as correct, and may mark a valid answer as incorrect.)

This is truly the most evil puzzle on my blog so far. Expect to use every single constraint in the rules, along with a bunch of techniques you may have not encountered before. I honestly don't blame you if you stop trying after 10 seconds.

And remember, you have to prove uniqueness!

Puzzle #6

This is a Hashiwokakero puzzle.


Difficulty: medium

Theme: Clue overload and logic.


This puzzle is dedicated to my friend Akira, who hates Hashiwokakero puzzles after he was forced to speedsolve them in a ridiculously short amount of time.

How ridiculous? 100 puzzles in 20 minutes.

That equates to 12 seconds per puzzle. Maybe Ulrich Voigt might be able to do that on one puzzle or two. But I doubt even he could keep up that pace for a full 20 minutes.

Anyway, the 3-2-3-2 pattern in the centre is surprisingly common in Japanese-made Hashiwokakero puzzles. In any case, enjoy.

Rules of Hashiwokakero

Draw horizontal and vertical lines (bridges) connecting circles (islands) such that:

1. Between any two islands, there are at most two such bridges connecting them.
2. Bridges may not cross each other or pass over an island.
3. A number on an island indicates how many bridges connect it to some other island.
4. All islands are bridge-connected; i.e. it is possible to move from any island to any other island by only moving across bridges and islands.

Below is an example and its answer.

Puzzle #5

This is a Total Masyu puzzle, a variant of Masyu. In addition to the rules of Masyu, all possible circles have been given; i.e. it is not possible to add any more circles to the grid so that it is consistent with the solution.


Difficulty: hard

Theme: Clue minimalism and logic.

Puz-PRE link. (Note: While a valid solution to this puzzle will be marked as correct, Puz-PRE does not have the "total" constraint programmed in. The solver may incorrectly mark incorrect answers as correct.)

This is one of the most stunning puzzles I've ever made, I think. The break-in is almost completely original (in that I came up with it and then found that it was already used by someone else, like two other break-ins I've "discovered"). While this puzzle still isn't MellowMelon-difficulty (it'll take a long while before I get there!), and it doesn't require excessive trial and error, it's definitely not a Total Masyu for the uninitiated.

EDIT: Twitter user @That_Scar has asked the following question:
@edderiofer Am I stupid or is this pretty easy? [SOLUTION IMAGE REDACTED]
— ThatScar (@That_Scar) September 16, 2016
To this, I respond that I don't consider a logic puzzle to be solved unless one has proven uniqueness of solution. Finding a solution may be easy, but proving that it's unique is the hard part.

Rules of Masyu

Draw a single loop through the centres of some cells according to the following rules:

1. The loop may only travel horizontally or vertically, never diagonally; all turns are right-angled turns. The loop may only turn at the centers of grid cells. The loop may not cross itself or branch off; that is, from any cell centre, there can be only 0 or 2 loop segments extending from it.
2. The loop must pass through every circle.
3. The loop may not turn at a white circle, but must turn at at least one of the adjacent cells in the loop.
4. The loop must turn at a black circle, but may not turn at either of the adjacent cells in the loop.

Below is an example and its answer.

Puzzle #4

This is an Akari puzzle.



Difficulty: medium

Theme: Tribute.

Puz-PRE link.

Today is the 29th birthday of Grant Fikes, the person who expanded my knowledge of the different genres of logic puzzles out there and thus got me hooked on them in the first place. This puzzle is dedicated to him.

Puzzle #3

This is an Akari puzzle.



Difficulty: medium

Theme: Few givens

Puz-PRE link.

This tweet refers to the previous puzzle, which I did say was trivial. So have a harder Akari, if you think Akari in general is boring and useful only for eye-candy.

Meanwhile, here's what my father said about it:
Congratulations for your new puzzle! I looked at it, and to be honest, I have no idea how to start. I just wonder how many people in this planet could solve this puzzle? How long will they take?
Answer: Many people, and 3 minutes.