Some combinations of constraints are difficult for people with colorblindness. So there’s a version of this puzzle as I initially intended it, but a friend with deuteranopia very patiently reviewed more than a half-dozen different attempts to ensure the pink and green cages were easily distinguishable, and this is the version that was clearest for him. So it’s the official version.
I’ll save the punchline for those who solve the puzzle. It’s the end of another month, and so time for another Gattai! This will also bring this run of Renban puzzles to close. For now. I do like Renban as a constraint, but I’ll try to mix things up for a while.
Once a month, I post a Gattai, and usually each grid has a separate constraint. This month, five grids, a full Samurai Sudoku, but they are all classic Sudoku, with diagonal lines the only extra rule. This title is redundant, since 侍 is the character for “Samurai,” making the title “Samurai Samurai Samurai.”
The challenges in creating these larger puzzles are multiple. I could have created more than four single-grid puzzles in less time than it took to create this one, in part because each change required me to re-solve the puzzle from the start, to be sure I hadn’t broken anything unexpectedly. Still, the satisfaction of a working gattai that also follows the rules I’ve set for myself, it’s worth spending the extra time on one out of every dozen puzzles or so.
I think the world would likely be a slightly better place with no kings anywhere at all. I’m pretty republican in that anti-monarchy sense. But I’m not calling for violence! I just don’t believe any sort of unitary authority can safely exist, and would like all those who attempt such things to be stopped from doing so.
Overlapping grids are interesting, but I thought: why always align on thick region borders? What if I split them offset? The answer is: it is a much more difficult puzzle to set, but makes solving more interesting. Trivia: When I set my normal logical auto-solver to the settings I like to use for testing, it gets “stuck” at one particular step. So if you solve the puzzle without using the walkthrough, you’ve done a better job than my logical auto-solver! Even more trivial: The renban lines are almost perfectly symmetrical, but there are two differences.
It’s a big one, and it’s anchored by Gravity Cages at the bottom. While these cages don’t directly affect anything else in the puzzle, I like to imagine they’ll combine to form a black hole, pulling everything in all four grids into a single cell.
Not a Sudoku-X puzzle, since only the “positive” diagonal is marked. Still, the unmarked diagonal is interesting. And not just on a global scale!
Continued research into the issue of Anti-Quadruples has exposed why we had not seen them before. They are best detected not by observing them directly, but by observing what isn’t there.
There’s really no point in having two fully-populated quadruples clues in a box. They only touch seven cells between them, so giving you four digits is overkill.