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Questions tagged [grid-deduction]

Puzzles such as Sudoku or Kakuro, where the final state of a pre-existing grid must be deduced logically through clues placed within and/or around the grid. For puzzles where you are given a list of clues which can be used to compose a grid to solve them logically, use the [logic-grid] tag instead.

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11
votes
3answers
525 views

Intersection Puzzle

I have invented a new puzzle called Intersection. Let's find out what it is! Intersection You are given an $n\times n$ grid with circles and boxes inside arbitrary squares. A circle cannot be in the ...
10
votes
1answer
523 views

Oriental House: An original grid-deduction challenge

A different approach to an old concept of mine, Oriental House is a new grid-deduction puzzle based once again off exits and entries. The rules are as follows: Draw a path from S to F, passing ...
10
votes
4answers
1k views

JonMark Perry's Grid Logic Puzzle

Consider the following puzzle type proposed by JonMark Perry. Start with a square grid of arrows, each one pointing in one of the four cardinal directions. For example: You start at the ...
10
votes
1answer
328 views

3D nonogram – What's in the box?

This is a three-dimensional nonogram. The first six squares depict the layers of a $6\times6\times6$ cube. The final square gives the enumerations for the Z-axis, top to bottom. Some rules: The grid ...
26
votes
4answers
1k views

Curiouser and Curiouser

CHAPTER ONE Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do: when she was overcome with the strangest sense of deja vu, and saw a 7x3 grid of ...
19
votes
2answers
1k views

Heyawake: An Introductory Puzzle

This is a Heyawake ("divided rooms") puzzle. Rules of Heyawake: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. ...
16
votes
1answer
781 views

HAISU: Nought and Crosses

HAISU is a portmanteau of three Japanese words - 'hairu', to enter, 'su', number, and 'hausu', an English borrow word meaning house, of course. Together, we get a meaning of 'enter number house', ...
15
votes
2answers
458 views

Heyawacky: Ace of Cups

This is a Heyawacky puzzle. The rules are the same as Heyawake, but non-rectangular regions are allowed. Rules of Heyawake: Shade some cells of the grid. Shaded cells cannot be orthogonally ...
14
votes
2answers
499 views

Adderlink: Almost symmetrical

Rules: Hey, this looks like slitherlink! In fact, it is two slitherlinks added together. So both of the two slitherlinks have clues in exactly the same locations as this grid below. Furthermore, a 2 ...
13
votes
1answer
285 views

Statue View: Raindrops

This is a Statue View puzzle, an original invention combining two logic puzzle genres: Statue Park and Canal View. It is harder than my previous Statue View, so you may want to start there. Rules of ...
12
votes
2answers
841 views

The Peculiar File

So I was browsing through my computer files earlier and I found a file I'd not seen before. I was wondering if you guys could help me figure out what it's about. This is where I found it: This is ...
11
votes
1answer
182 views

Rhombicosidodecahedron Slitherlink

This is a Slitherlink puzzle, being played on the surface of a 3D object, a Rhombicosidodecahedron. If you are not familiar with Slitherlink puzzles, I don't suggest starting on this one. Rules in ...
10
votes
1answer
288 views

Double feature: Legal trouble

This puzzle is part 6 of the Double feature series (first part here). The series will continue in "Double feature: Weightier". Rules of Hitori1 Shade some cells in the grid. No ...
9
votes
1answer
1k views

What is a “unique solution” in a Slitherlink puzzle?

In the question Five Slitherlinks, the querent suggests that "each [Slitherlink puzzle has] a complete solution". I'm newly reading about Slitherlinks, but I don't understand what makes a solution "...
9
votes
2answers
576 views

Haisu: Pixel Perfect

HAISU is a portmanteau of three Japanese words - 'hairu', to enter, 'su', number, and 'hausu', an English borrow word meaning house, of course. Together, we get a meaning of 'enter number house', ...
8
votes
2answers
274 views

Double feature: In concert

This puzzle is part 3 of the Double feature series (first part here). The series will continue in "Double feature: Hot stuff". Rules of Ripple Effect1 Fill the grid so that each cell ...
8
votes
1answer
192 views

Double feature: Russian desman

This puzzle is part 2 of the Double feature series (first part here). The series will continue in "Double feature: In concert". Rules of Masyu1 Make a single loop which goes through ...
8
votes
1answer
441 views

I'm Bad at Naming Things, so Just Try to Solve this Patterned Masyu Puzzle!

$\hskip1in$ The original Masyu rules apply. Make a single loop with lines passing through the centers of cells, horizontally or vertically. The loop never crosses itself, branches off, ...
8
votes
3answers
535 views

Ambiguous Grids

After six to eight weeks of waiting, your Shmikoli™ Ambiguous Grid Deduction Puzzle Set has finally arrived! You tear into the box only to discover that the instructions are missing. You shouldn't ...
8
votes
4answers
434 views

A “Find the Path” Puzzle

I invented a puzzle, inspired by Simon Tatham's Portable Puzzle Collection. Is there anything that it could improve on? Was it too easy, or was it too hard? Anything I could add? What must I call it? ...
8
votes
1answer
323 views

Double feature: In cold blood

This puzzle is part 5 of the Double feature series (first part here). The series will continue in "Double feature: Legal trouble". Rules of Nurikabe1 Shade some cells in the grid. ...
8
votes
2answers
748 views

A spartan skeleton Sudoku

A skeleton crossword is a crossword where the black and white squares aren't given; you have to deduce them. Here's a generalisation of that idea to the Sudoku puzzle. Here's a 4 by 4 grid, with four ...
7
votes
1answer
199 views

Latin Square Puzzle - Difficult

Follow on puzzle from the introductory Latin square puzzle post. The rules It’s a Latin square like sudoku, so there must be the numbers 1-9 exactly once in every row and column. Notice that each ...
7
votes
2answers
295 views

Quick Yajilin Puzzles: Scatter and Gather

Yajilin (adapted from Nikoli) Draw a line to make a single loop. Lines pass through the centers of cells, horizontally, vertically, or turning. The loop never crosses itself, branches off, ...
6
votes
1answer
234 views

3D tetromino placement

The following image depicts a $5\times5\times5$ cube. Insert any number of the pictured 3D-tetromino pieces into the cube to satisfy the conditions listed below. Pieces may be rotated in any direction....
5
votes
1answer
182 views

Double feature: Hot stuff

This puzzle is part 4 of the Double feature series (first part here). The series will continue in "Double feature: In cold blood". Rules of Heyawake1 Shade some cells in the grid. ...
5
votes
2answers
449 views

Simple grid deduction puzzle

I will let you figure the rules of this one yourselves. Here is the empty grid to assist solvers. Here is a text version of the grid: ...
5
votes
2answers
673 views

Incomplete Word Rectangle

This is an incomplete word rectangle: When completed, every row will contain a common English word with four letters, and every column will contain a word with five letters. All of these are common ...
3
votes
2answers
474 views

36-length snake in a 6x6 grid

Based on https://brilliant.org/weekly-problems/2017-05-29/advanced/?p=4 We need to fill a 6x6 grid using the numbers 1-36, each cell having a single unique number, such that: Every two consecutive ...
-4
votes
10answers
928 views

SafeCracker #3 - We've Been Blocked [closed]

Our Last Safe To Conquer Ok, team, this one might give us a little trouble. Nothing we can't handle though... let's go... This safe model is "The NevaCrak 9000" - the most secure safe there is. ...
22
votes
1answer
1k views

Help! Can you get my puzzle back?

Puzzling has a lot of really complicated stuff these days, so I just wanted to post a simple Boggle grid. You know that game, right? You form words by starting from one letter, then taking adjacent ...
14
votes
2answers
657 views

3D Masyu - A Die

Fold this net into a cube and solve this 3D Masyu. The original Masyu rules apply. In addition, question mark '?' should be replaced by either a black or white circle. Side note: Yeah, it's almost ...
13
votes
2answers
548 views

Double n-queen puzzle, with sudoku rules

Put 9 blue queens and 9 pink queens, with rules : If the blue queens removed, each pink queens do not attack each other. If the pink queens removed, each blue queens do not attack each other. Each 3×...
12
votes
2answers
377 views

The Terrible Twos of Slitherlink

This question is aimed at people who have a really good grasp of standard Slitherlink puzzles. This is a standard, square cell, 10x10 Slitherlink puzzle I designed. It isn't what I would call a "...
11
votes
2answers
726 views

Twelve Labours - #02 Lernaean Hydration

This puzzle is part of the ‘Twelve Labours’ series. Previous instalments can be found here: Prologue | 01 His first labour now complete, Hercules made his way up the street to the storage depot for ...
10
votes
2answers
199 views

Lazy puzzler's masyu

The creator of this masyu forgot to add the final stone, so the puzzle remains incomplete. Finish his job for him by placing one additional stone (either black or white) on the board so that the ...
9
votes
2answers
524 views

Tetromi-nuri-doku

Note: This puzzle was inspired by the one here, by Mike Q. Every square in the grid above, when the puzzle is complete, has a number between 1 and 9 in it and either is shaded or is not. Each 3x3 ...
9
votes
2answers
448 views

Cryptic Crossword Sudoku

This puzzle is inspired by Matt’s excellent Cryptic Sucrosswordoku. Below is a sudoku as well as some cryptic clues. The clues lack enumeration and are in no particular order. The solutions to the ...
8
votes
2answers
287 views

Not Just Black and White

Answer for this puzzle is one word. Have fun! Highlighted parts are where I realised I have clued it wrong... Sorry for all this inconvenience! Hint: usefulness level 1 usefulness level 2 This ...
8
votes
1answer
278 views

Puzzles: Meander

I have come up with an interesting type of puzzle based on the mathematical concept of a meander. The concept, of course, is not original to me, but the type of puzzle is, as far as I know. A ...
8
votes
4answers
493 views

The Knights and the Hounds

(With thanks and congratulations to Lee Leon) We rejoin our heroes several days after the events of The Knights' Gift, at the head of a pack of enormous staghounds, 1000 strong. Such a pack ...
7
votes
2answers
278 views

Nono-cube - Ultimate Puzzle Giant

Prologue - Instructions Shamelessly copied and pasted the following from @jafe's puzzle :P This is a three-dimensional nonogram. The first square gives the enumerations for the Z-axis, top to ...
7
votes
1answer
367 views

Latin square puzzle

This is a sudoku-esque puzzle I came up with when trying to solve some harder sudoku. The rules It’s a Latin square like sudoku, so there must be the numbers 1-9 exactly once in every row and ...
7
votes
1answer
193 views

Nono-Cube: Approach at Your Own Risk

Inspired by jafe's 3D nonograms :) Answer is one word. This puzzle is a part of Ooohh, it all makes sense now! :D
6
votes
1answer
442 views

ASCII Art Painting

I've been taking an art course recently, and I met someone who was proficient with grid ASCII art paintings. However, the teacher of the class always seemed to think there was something wrong with his ...
6
votes
1answer
303 views

My featured entry

Mosaic is a Minesweeper-like puzzle based on a grid with a pixel-art picture hidden inside. Using logic alone, the solver determines which squares are painted and which should remain empty until the ...
6
votes
1answer
145 views

The Terrible Twos of Slitherlink Part Deux

Please read and understand my first question before proceeding. This one should be worse. pdf files I uploaded to Dropbox: Slitherlink of Twos Their solutions These puzzles were generated by ...
5
votes
1answer
265 views

Haisu: Pink Rose

HAISU is a portmanteau of three Japanese words - 'hairu', to enter, 'su', number, and 'hausu', an English borrow word meaning house, of course. Together, we get a meaning of 'enter number house', ...
5
votes
4answers
261 views

Fill the grid (pattern)

Can you guess what comes in place of the question mark? Here's a text-based version of the table: ...
5
votes
2answers
282 views

A game of cricket

This puzzle is part 14 of Gladys' journey across the globe. Each part can be solved independently. Nevertheless, if you are new to the series, feel free to start at the beginning: Introducing Gladys. ...