Island Hopping
I made a complicated variant of sudoku that nearly broke the current Times cryptic crossword champion. I didn't think it was that that tricky for a former member of the UK's world sudoku championship team, but the number of times he wonders if the puzzle is even possible to finish makes me rethink that assessment.
You can try it yourself here: sudokupad.app/e7kgnmlm76 if you dare. Or just watch Mark having a bad time for over an hour in the video.
(
VicJameson : fucking internet virgins since, Fri 9 Oct 2026, 13:13,
Reply)
I don't even understand the rules.
What is the difference between water and island if both are represented by numbers 1-9?
(, Fri 9 Oct 2026, 14:52, Reply)
Yeah, if this is your first exposure to weird-rules sudoku then you're being thrown in at the deep end somewhat.
You need to work out where the islands are and how big they are in order to figure out where some of the numbers are - or aren't. For instance, because numbers can't repeat on an island, if you don't know which cells the islands occupy then you can't work out which numbers need to be excluded from them. Also, if you don't know how big the islands are then you can't get the numbers in the circles.
It's knowing that the circled numbers denote the size of the islands, in conjunction with what numbers it's possible to use in the black dot doubling relationships that should give you your first digit in the puzzle. It's really useful to have the colouring option that the app gives you to keep track of water/island cells. Something you can't really do for a pen and paper puzzle.
(
VicJameson : fucking internet virgins since, Fri 9 Oct 2026, 15:21,
Reply)
It makes less sense for me
but not to worry, sudoku is not my bag anyway.
(
brb man-child cuck corporate supplicant fuck, Fri 9 Oct 2026, 18:18,
Reply)
Very nice
I'm stuck having got the first 9 numbers. Not watched Mark yet though
(
Boot I want to know what you meant, Sat 10 Oct 2026, 15:33,
Reply)
Thanks
I often find an easy break in can lull you into a false sense of how tough it can be, and it definitely has some tricky bits. Figuring out where to look for the next step can be the most challenging part. It ends up having the more difficult logic on the right of the grid and easier parts on the left.
(
VicJameson : fucking internet virgins since, Sat 10 Oct 2026, 16:12,
Reply)
Yeah - doesn't help that I'm losing my marbles :-)
If you ever think to write a blog post on how you go about creating these things in general, I'd be fascinated to read it
(
Boot I want to know what you meant, Sat 10 Oct 2026, 20:15,
Reply)
Once I have bit more experience I might do that and I'll share it here. This is the first sudoku puzzle I've made though, so I've still got a lot to learn myself.
(
VicJameson : fucking internet virgins since, Sun 11 Oct 2026, 14:08,
Reply)
That was crackin'
Took me the best part of an hour and a half of solving, got properly stuck at the end and had to sleep on it. Woke up, saw the reduction of r6c6 and that was it. Thanks.
(, Sun 11 Oct 2026, 7:51, Reply)
Glad you got there in the end.
I've had the same experience, where taking a break from a puzzle that has become intransigent helps. Coming back to it with fresh eyes and somehow my mind is now ready to see things it refused to before.
(
VicJameson : fucking internet virgins since, Sun 11 Oct 2026, 14:16,
Reply)
Wow
Ended up watching it all the way through. Fascinating to see his thinking process. Just about held on
(, Mon 12 Oct 2026, 13:19, Reply)