Puzzles #652, #653 & #654 - IPC Round 3 (Killer Doppelblock, Clone Snake)

Like last year, I helped contribute to the Indian Puzzle Championship this year. If you're interested in seeing the rest of the set, including bonus puzzles, check the link for details on how.

Round 3 was themed on taking sudoku variants and applying them to non-sudoku puzzles. I put myself down for number placement, wanting to make a puzzle of a type that has arithmetic normally combined with killer cages. I thought about a few types before settling on Doppelblock. I also signed up for clone Snake since I knew the combination had potential from old, old Islands of Insight rule prototyping. In fact, now that that game isn't getting new content, I know a lot of these old unused puzzles will stay unused, so retain all the rights to them. I've gone through my archive and have about 80 puzzles in this category I think are good enough to share, so at some point I'll have to set up solving interfaces/write rules/share them.

Anyway, Killer Doppelblock! Standard Doppelblock rules apply. Additionally, all the numbers inside a cage add up to the number in the corner of the cage. This is a pretty cool combination, where the different ways of getting partial sums interact in some really cool ways. This was worth 65 points.

penpa interface

Clone Snake: Standard Snake rules apply, with given endpoints and an unknown length. Two cages of the same shape and orientation must have the same arrangement of snake and not snake cells. The first puzzle here is actually one of those old IOI prototype puzzles, since I added it to the organization sheet after a couple failed constructions, to at least have a puzzle in the slot. I put a note that this was from a couple years ago and I didn't think anyone at the IPC would have seen it before. A few hours later, I finally turned up a satisfactory second puzzle, and added that to the sheet to provide an option for which puzzle to use. Prasanna chose both, worth 30 and 50 points.

penpa interface

penpa interface

Puzzles #649, #650 & #651 - IPC Round 1 (Fivecells, Cave, Yajilin)

Like last year, I helped contribute to the Indian Puzzle Championship this year. If you're interested in seeing the rest of the set, including bonus puzzles, check the link for details on how.

As usual, round 1 revisits puzzle types that appeared in Puzzle Ramayan throughout the year. I contributed 3 puzzles to this round, a 55 point Fivecells, a 30 point Cave, and a 25 point Yajilin.

I had a really tough time settling on a theme for my region division pick, but once I thought of putting pentominoes of clues into the grid, I had to run with it. It was a small step from there to try pentominoes of only 3s, and some initial steps proved quite workable and interesting, so I kept pushing at that idea until I had a finished puzzle. I'm a bit sad about the diagonal touching, but there was no way around it and the theme is still quite clear.

puzz.link interface

Cave was an option. I like Cave. I'm good at making Caves. So for some reason I tried to find a valid, interesting puzzle with this layout, and suffered for hours with multiple very close attempts that were a single ambiguous cell away. I also didn't start from this full layout, just one half with a cool opening, and eventually tried for the full symmetry after finding no good continuation.

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Originally I had just claimed two spots in round 1, but the evergreens category remained empty as the deadline approached. So I made a Yajilin for the slot, didn't like it, made another Yajilin for the spot, thought it was a bit rough in the middle, and made yet another for the spot, which is this puzzle. This is a pretty slick layout I think, the bigger tilted square works really well for Yajilin.

puzz.link interface

Puzzle #648 - Choco Banana

Lately, when I can't fall asleep, I tend to either do some reading, or make a puzzle. Last night was the latter, so I took a stab at making a Choco Banana with a theme I'd thought of a couple days prior but hadn't gotten around to trying to make yet. I like how this one came out quite a bit, and decided to crosspost it to puzsq since I think it's a puzzle the regulars there will really appreciate.

puzz.link interface      puzsq link

I've got another 20 or so unpublished puzzles I haven't gotten around to posting yet - had a lot going on and haven't really found the time to queue things up. Hopefully I get to it soon? This space isn't dead, you hear!

Puzzle #647 - Four One (Tapa)

This is the best puzzle I've ever made. GMPuzzles wishes they could have Tapa puzzles as incredible as this one. Toketa would be jealous of the sheer beauty of this construction.

...what do you mean, it's bashy?

puzz.link interface

I'd wish you good luck, but solving this puzzle will never happen. It's literally impossible. A lie, a myth, a farce propagated by the government to mislead the ignorant. Anyone who thinks it's possible is stupid and should feel ashamed, and can wallow in their own lack of intelligence. This is an irreversible fact of logic puzzling and simply cannot be challenged. Go cry about it, nerds.

I'm not late for publishing this, it's still April 1st in my time zone!

Puzzle #646 - Numbers are Overrated (Nurimisaki)

Someone in Puzzlers Club mentioned a Nurimisaki pattern that would force a deduction, which put me in the mood to make one. So I did, finding my own neat pattern that somehow managed to finish without needing any clue numbers. This is such a fun genre.

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Puzzle #645 - S is for... (Slitherlink)

I completely forgot I had this old Slitherlink lying around until recently. It was originally intended for PuzzleDuel until I made a puzzle I liked better for that role, and then this one just say in my spreadsheet for months and months, forgotten. There's not even anything really wrong with this puzzle either, it's just a bit plain.

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Puzzle #644 - Two Good (Akari)

I don't have a witty comment for this Akari puzzle. The reason I made it was I linked a friend pzprrt, messed around and made a bashy puzzle afterwards, and felt bad and wanted to make a legit puzzle. So I made this one, which I like quite a bit.

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I then made something even worse than the other bashy puzzle. Look at it. Just look at it.

Horrifying.

Puzzles #641, #642 & #643 - Almost Symmetric (Masyu)

About 3 months ago at this point, I got a bit obsessed with trying to make a non-trivial Masyu that was almost symmetric in its clue layout, but didn't solve symmetrically. The second puzzle I made was a small one based on a simple yet somewhat advanced idea.

puzz.link interface

Another interpretation of the theme would be to have a symmetric clue layout with only a minor "blemish" from being fully symmetric. My third attempt - still posting out of order - ended up with two such pearls and a fill that got a little bit insane in the end.

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Ultimately though, I think my first attempt at this theme was the best. Definitely the hardest break-in of the three, and though the later stages are easier than the prior puzzle that's not really saying much.

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Thus concludes my backlog of unposted puzzles. With any luck, I'll have more queued and ready to go by the time you're reading this, but no promises!

Puzzle #640 - Fourced (Light and Shadow)

Light and Shadow is still such a good puzzle type. I spent a while toying with this layout of 4s and trying to find any good solution for several white layouts, with all white clues being question marks, before finally finding one. The first version was super bashy and I wasn't going to share the puzzle widely, but something compelled me to keep tweaking it and before long I actually did find a fair, albeit hard variant.

puzz.link interface

Also, these rules could potentially appear in Islands of Insight, which should launch about a week ago (I'm writing this on January 25th and may not update this space before it goes live). I've worked really hard on that game, especially the puzzle content for the past 3 years and I'm really, really excited for it to be out there for anyone to see.

Sometime around my birthday, I might post a collection of my favorite puzzles from the game. Regardless of your puzzle experience level, you won't be disappointed!

Puzzle #639 - Chained Again (Yajilin)

A few years after the first Yajilin chains on Puzzlers Club (apparently about 4.5 years), the old spreadsheet was rediscovered. Somebody noted that the amount of givens would always be an even number, so... I made a starting point with an odd number, which also served as a way of unsticking the chain, as it must be constructed linearly.

puzz.link interface