**Rules** Place the given set of dominoes in the marked domino tiles. Whenever two dominoes touch by an edge, the adjacent numbers must be the same. Clues outside the grid are skyscraper clues: They indicate the number of visible skyscrapers when looking along the corresponding row or column from that point, where each number represents a skyscraper of that height. Skyscrapers are blocked from view by those of greater or equal height.

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These originally came out of practicing my Sudoku construction skills by writing a puzzle a day for a long week early last year. It’s still a hit-or-miss process for me, but I think there were some nice ones. Solve on PZV (a b c d e f g h i) or find the set below.

In other news, don’t forget to take part in Puzzle Ramayan at LMI this weekend: A set of easyish classics and region puzzles that I prepared, including some instructionless variants.

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The objective was to construct a 10×10 Masyu puzzle that leaves over a battle ship fleet of empty cells while minimizing the number of clues. That turned out to be quite a fun challenge, and led to some rather nice puzzles, which I didn’t quite expect. I was a bit worried the contest would be won by optimal computer-generated submissions, but it seems no one went to that effort. Instead, I’m left curious as to how close to the optimimum we got with 8+7 clues.

Here are my two submissions (rules).(solve on pzv.jp)

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One of the construction rounds, the Pole Vault, gave you three tries at constructing a high-scoring Easy as ABC puzzle: Before each attempt, you chose a grid size, then had 15 minutes to extend a partially clued puzzle of that size to a correct puzzle. The score was calculated by subtracting twice the number of added outside clues, five times the number of inside clues and once the number of diagonal adjacencies in the solution from ten times the number of rows/columns. I had a rough start there, but ended up with a pretty good third try, with this 8 by 8 puzzle.

**Rules** Place letters A-C into the grid so that each letter occurs once in each row and column. Clues indicate the first letter in the corresponding row or column.

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Individual puzzles below, or get the whole set in PDF: 2016-24h-rob-puzzles.

**Sudoku** (rules) Just something easy to start, classic Sudokus.

**Kropki** (rules) I was writing this set close to the 2016 Slovakian GP, which featured Kropki as a type, so these were in part familiarizing myself with the type. I think these came out quite well.

**Persistence of Memory** (rules) A loopy type, this one works quite well, but the rules are a bit awkward.

**Japanese Sums** (rules) A few of these turned out a bit unusual.

**Checkered Fillomino** (rules) The obligatory Checkered Fillominos.

**ABCtje** (rules) Not one of my favourite types, part of the purpose of constructing these was to understand the type better. Not sure it helped, but they’re easier to construct than to solve. The fourth one was the highest valued, but logically the easiest.

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**Rules** Shade some cells, so that all shaded cells are connected, and such that shaded cells don’t fill any 2×2 square. Clues indicated the number of shaded cells in an area; each area must have at least one shaded cell. Whenever two shaded cells touch across walls, the number of shaded cells within both areas must be different.

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In other news, I’ve been writing some puzzle sets for Nibbl (Android, iPhone). It’s an app that works as a solving interface and marketplace for handmade puzzles. See also Rohan’s announcement from earlier this year; the interface has been improved quite a bit since then. If you use my referral code ROBR9402 (or someone else’s), you’ll start with 100 credits, with which you should buy some of my star battle or skyscraper puzzles which came out pretty well.

I won’t stop posting here, though, don’t worry!

**Rules** Place a full set of twelve pentominoes in the grid. Different pentominoes must not touch along an edge; they may touch diagonally. Black circles must be part of pentominoes, white circles must not. All cells that are not part of the pentominoes must be connected by edge.

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**Rules** Fill the cells with numbers 1 to 9, so that no number repeats in a row, column or outlined 3×3 square. Whenever a number is equal to the sum of some numbers in a diagonal direction, an arrow is placed pointing there.

(The standard rules also have arrows pointing horizontally and vertically.)

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**Rules** Shade some cells, to leave a connected area of unshaded cells that includes all given numbers and doesn’t cover any 2×2 square. Some shaded cells are given. Numbers indicate how many other numbers can be reached through unshaded, unnumbered cells.

**Example** (a poor example: shaded cells can be adjacent)

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**Rules** Place some lamps in the empty cells around the grid, with brightness 0 to 3. The lamps shine horizontally, vertically and diagonally in eight directions. In each direction, they illuminate as many cells as they are bright. Numbers inside the grid indicate how many lamps illuminate the corresponding cell.

The WPC instruction booklet has an example.

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