Diagonal

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.

Irish pub cuisine, or a Gattai-3 Sudoku puzzle? You decide!

It's a Sudoku-X! It's a spiral of givens! It's oh-so-many easy-to-find "naked" singles!

It’s an X-Killer, get it? Okay, it’s not very subtle.

It may seem like a lot of constraints, but it's a Samurai Sudoku, so you should only have deal with one or two at a time.

Not a commentary on computer operating systems at all.