Puzzle #24

This is The Terrifying Torus, an original mashup puzzle. Rules are given below the image.

Difficulty: hard

Theme: Secret Santa Gift for TheGreatEscaper

PDF

Swaroop Penpa (To have the answer checker confirm your solution, all lines, and only those lines, that lie in the centre 16x16 grid must be drawn.)

Rules: The puzzle is the centre 16x16 grid. It is divided into four 8x8 quadrants, and is toroidal, so the left and right sides connect to one another, as do the top and bottom sides. Faint copies of the adjacent grids are added for convenience.

Draw a single loop, whose vertices are grid vertices, that doesn't branch, and whose segments may travel in any direction, not just compass directions. Each visit of the loop to a region must contain a turn. Additionally, if any segment lies in a quadrant, then it must obey the rules of that quadrant:

• The top left quadrant is Kouchoku: Every loop vertex in this quadrant must be at a clue. Every visit to this quadrant must begin and end on a dot. All copies of the same letter must be connected by a path passing through no other dots or letters, and different letters may not be connected. All dots and letters must be used by the loop. A 180° angle at a vertex is allowed in this quadrant. The loop may intersect itself in this quadrant, but ONLY at right angles. (Colouring is for cosmetic purposes only.)
• The top right quadrant is Keima Loop: Every loop vertex in this quadrant must be at a star. Pass through all stars, using only edges that are knight moves. A 180° angle at a vertex is allowed in this quadrant, but the loop may not intersect itself in this quadrant. Note that any loop segment going into or out of this region must be a knight move as well.
• Bottom left quadrant is Total Omnidirectional Midloop: Pass through all dots, such that each dot is the midpoint of an edge. All dots are given. The loop is not allowed to have a 180° angle in this quadrant, nor may it intersect itself in this quadrant. (Note that any loop segment going into or out of this region must be clued with a dot.)
• Bottom right quadrant is Angle Loop: Every loop vertex in this quadrant must be at a clue and vice versa. A triangle indicates that the angle at that vertex is acute; a square, right; a pentagon, obtuse. The loop is not allowed to have a 180° angle in this quadrant, nor may it intersect itself in this quadrant.

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Another Secret Solver puzzle from Puzzlers Club; this time for 2020 and TheGreatEscaper. No solution or example is provided this time, because frankly I can't be bothered.

As with the previous one, I'm giving this a "hard" simply because two of these genres are novel, and non-orthogonal loops are generally not a thing people are fine with dealing with.

Special thanks to SoftFro for typesetting this in Tikz, and to montelucci, rand_yosh314, jkittykitkat, Jamie Hargrove, boboquack, Deusovi, and SoftFro once again for testing this.

Puzzle #23

   This is a Kurodoko puzzle.

Difficulty: hard

Theme: logical

Puzz.link link. 

Found this one deduction in a different puzzle, made a puzzle to properly exploit it. If you know what you're looking for, though, this is a breeze.

Puzzle #20

This is an Numbered Arrows Mashup Loop puzzle, an original mashup genre. Rules are given below the image.

Difficulty: hard

Theme: Secret Santa Gift for IHNN

PDF

Puzz.link (Note that the answer checking and clue colouring are nonexistent here, since this merely uses the Yajilin interface.)

Rules: Draw a loop through non-clue cells and shade the unused cells. Shaded cells may not be orthogonally adjacent (as in Yajilin). Each arrowed clue has a “line of sight” in the given direction, up until the edge of the grid. In addition, each quadrant's clues behave differently:

• Clues in the top-left quadrant are Yajilin clues; they indicate the number of shaded cells in the clue's line of sight.
• Clues in the top-right are Castle Wall clues; they indicate the total length of the loop segments along that clue's line of sight.
• Clues in the bottom-left quadrant are Slalom Count clues; they indicate the number of times the loop passes straight across the line of sight of the clue without turning. (Note that this type of clue does NOT count occurrences of the loop passing through the line of sight when turning, and that the loop is allowed to behave in this way regardless.)
• Clues in the bottom-right quadrant are First Seen Geradeweg clues; they indicate the length of the first-seen loop segment; if the first-seen cell used by the loop is a corner, both segments incident to that corner must be of that length.

(The small images around the puzzle are to remind you what each clue does.)

Below is an example and its solution:

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I actually constructed this one for Puzzlers Club's annual Secret Solver event last year and only just got around to posting it now. Secret Solver is our version of Secret Santa, wherein everyone participating writes a puzzle for someone else. In this case, I had to write a puzzle for IHNN.

A full walkthrough and writeup can be seen here (but please don't read it until you've at least had a good crack at the puzzle). Many thanks to SoftFro for creating the images and PDF.

Even though, having constructed it, I think it's a medium, I'm rating it as "hard" just in case, and in part due to the fact that two of these genres are novel.

Anyway, I should probably get around to porting most of my puzzles to this blog (except maybe the ones I'm submitting elsewhere?). I've been constructing puzzles occasionally for the last 6 or so years, so I *should* have a pretty reasonable backlog. (Then again, a ton of them are "easy" by my standards and I don't necessarily want to flood the blog with them...)

Puzzle #14

This is a Double Choco puzzle. I can't be bothered to write rules pages for every single genre that I come across any more, so the rules are below.

Difficulty: hard

Theme: Valentine's Day

Puzz.link link.

Divide the grid along the grid lines into orthogonally-connected regions. Each region should have exactly one grey half and exactly one white half; each half-region should be orthogonally connected, and the two halves should be exactly congruent. Numbers indicate the size of the half-region containing them; a region can have zero, one, two, or more numbers inside it.

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Apparently Japanese Puzzle Twitter is making a bunch of these for Valentine's Day, so I thought I'd join in the fun. However, the latter half of the puzzle was difficult to finish off and I ended up enlisting the help of Puzzlers Club. Thanks to ManyPinkHats for coming up with a good end. It's still quite casebashy, though, so you have been warned.

Puzzle #13

This is a Go puzzle.

Oh wait no, it's actually a Masyu. (Click on image to get a Masyu grid. With hope, this will work, though I'm not immediately sure as Blogspot's "Preview" option doesn't allow you to click on links.)

Difficulty: hard

Theme: White Wins

Puz-PRE link.

I made a joke when watching someone stream Go (aka Baduk, aka Weiqi), about Go positions actually being Masyu positions. Several weeks later, the idea was still bobbing around in my head, so I made this weird puzzle to go in a post on /r/badukshitposting. It also involves repeated application of a trick that should be known to all intermediate/advanced Masyu solvers.

(To save you unnecessary checking, there are no "3-white-circles-in-a-row" configurations in this position.)

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.