Kropki

These digits are not just good friends, not even just best friends. That’s a relative term, after all, not an absolute term. These digit pairs aren’t just best friend, they’re inseparable. Just try it: you’ll break the puzzle!

Bonus puzzle! SudokuBank is brand-new, just two days old, and has a lot of appeal for both puzzle setters and puzzle solvers. I was invited to set a puzzle for the launch, and this is the result. As a setter, SudokuBank includes many constraints for which I normally would use custom code, like “Ambiguous Kropki Dots,” which are new to the blog. Each dot is either a white or black Kropki dot, but which? That’s up to you to determine!

Hands / Touching hands / Reaching out // Touching me, touching you // This is a Touchy Sudoku, which is a challenge to set and this version of this puzzle is a bit of a challenge to solve.

Keep smiling, keep shining / Knowing you can always count on me for sure // That’s what friends are for // In good times, in bad times / I’ll be on your side forevermore // Oh, that’s what friends are for // – Dionne Warwick

I don’t know what the punch line to this joke would be. Not a newspaper, not a penguin. Well, penguins are a bit odd, I guess. Could still be a penguin. I mean, literally the answer is this puzzle, right? Except I color odd and even cells, undermining the whole “black and white” part.

Some have guidelines about how much time to spend on social situations, while others go with the flow without any plan ahead of time. An hourglass tracks time without being disruptive, requiring one to notice that the flow of sand has ended. This puzzle includes an hourglass shape made of a Near Neighbor line. These are three completely-unrelated facts.

Sometimes I wish I hadn’t used “Every Other” in so many puzzle titles already, because Parity Lines are very deserving of the appellation. This puzzle was inspired by thoughts about odd and even digits, and how many of each are found within the standard set of Sudoku digits, so I thought of it as an “Every Other” puzzle until it came time to choose a title, at which point all creativity left me.

I have a mild obsession with the novels of Victor LaValle, including his 2009 novel Big Machine, several editions of which feature cover art of a spiraling line, including the audio edition I enjoyed. I often name puzzles as the last step, but in this case I started with the title and set the puzzle “inspired by” the cover art.

There’s a big green rectangle with some weird edges, and it anchors the grid. But there’s this weird rotating line careening wildly across the grid, with very different properties than the rectangle. It grabs a couple of points, but mostly takes its own path. Oh, and also a switch of sorts, a single black dot. I think of it as a circuit, with the peach line representing temporary wiring. But I’ve used that metaphor when naming other puzzles, so it’s time to pick names differently. Note: Some testers considered this a 1 or 1.5 difficulty, while others rated it 2.5 at least!

Some lines force digits to be far apart, while other lines force them to be close together. They only interact at a single point.