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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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19
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1answer
2k views

Make numbers 0 - 11 using the digits 2, 0, 1, 8; BUT

... seriously, this is definitely NOT that "kind of puzzle"! ;) So let me create this puzzle to freshen you up! It is inspired by a meta question: Yet another 2018 puzzle. Put the digits 2, 0, 1, ...
19
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1answer
537 views

Introducing Tetronogram - Beginner's Version

Introducing Tetronogram! (named by @MrPie) The puzzle is made of a grid like a nonogram. Notations are along the axes like a classic nonogram but numbers are replaced by the names of the ...
18
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2answers
608 views

Introducing: Jormungand

An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids Introducing: Jormungand A combination of Ouroboros (Slitherlink) and Numbersnake (Numbrix) to create the greatest snake-themed ...
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2answers
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Who can spot the difference?

My family and I have just moved house! Lucky us! So what did my family do? We held a housewarming party, and rung everyone in the neighbourhood up to invite them. So, anyway, people were coming in ...
18
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2answers
1k views

Three for the price of one

While browsing through your local puzzle store, you see something you can't resist: a box which promises two grid deduction puzzles for the price of one! The vendor explains that the box contains a ...
18
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1answer
893 views

A Total Masyu puzzle

In a Total Masyu puzzle, one must draw a single loop through the centres of some cells according to the following rules: The loop may only travel horizontally or vertically, never diagonally; all ...
18
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1answer
785 views

A Knight's Kuromasu

An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids You are a knight in the king's army, and you've been tasked with constructing some walls. The problem is, as a knight, you are ...
17
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3answers
1k views

Hexagonal Grid Filling

Fill in each blank white hexagon with a digit from 1 to 9. Each of the grey hexagons is the sum of the white hexagons around it, and all of the white hexagons that are around the same grey hexagon ...
17
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4answers
978 views

A letter from Mr. Pirate, Mr. Roller, and Mr. Knight

Though I don't think it will help, you may check with the beginning of my story concerning Red Herring Puzzle Club. It seems like it's been a long time since I tried to enter the R.H.P.C. As you may ...
17
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1answer
1k views

Sudoku with only 8 predefined numbers

Have fun with my self-made Sudoku puzzle. Solve this Sudoku puzzle using the standard Sudoku rules: Fill any row, column and bold-framed area with the numbers 1 to 9. Hint: It is not as difficult as ...
17
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2answers
705 views

Time to Hit the Bricks!

An entry in Fortnightly Topic Challenge #24: Grid-Deduction... It's 2am. The phone rings. You answer it and are immediately met with an onslaught of franticness from your (in?)famous uncle—a ...
17
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2answers
405 views

Unusual Kakuro Puzzle

Entry into Fortnightly Topic Challenge #38: Reusing Information 1 This puzzle sort of looks like a kakuro puzzle but there doesn't seem to be any sums. Figure out how this puzzle works and solve the ...
17
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1answer
341 views

Diabolical Deceptions: A 333rd Birthday Tribute to J.S. Bach

Johann Sebastian Bach is one of the most famous composers from the Baroque period. If he was still alive today, he’d be 333 years old. So, let’s celebrate 3 of his most famous works with a 33x33 loop ...
16
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1answer
320 views

Masyu-making game

Two players are playing a game on a $4\times4$ board. The players take turns adding either a white circle or a black circle into any empty square, so that the board makes a solvable masyu puzzle (with ...
16
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1answer
519 views

Statue Park: Knight's Lines

This is a Statue Park puzzle. Rules of Statue Park: Shade some cells of the grid to form the given set of pieces. Pieces may be rotated or reflected. Pieces cannot be orthogonally adjacent (though ...
16
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1answer
2k views

This puzzle design was a DISASTER!

As any member of the PSE community knows, grid-deduction puzzles really aren't my forte. In fact, I'd like to share one particularly disasterous attempt at designing a Slitherlink puzzle. Disclaimer:...
16
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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', ...
16
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3answers
483 views

Tiling a square with rectangles

Tile completely this 47 x 47 square with 52 rectangles. Each rectangle must contain precisely one numbered cell, and that number must be the area or perimeter of the rectangle it finds itself in. ...
16
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1answer
589 views

Barrel - Part 1

An entry in Fortnightly Topic Challenge #35: Restricted Title 1. Title based on the very first xkcd. Continued in Barrel - Part 2, Barrel - Part 3, Barrel - Part 4, and Barrel - Part 5. You manage a ...
16
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1answer
433 views

Karst - A variant of Cave

This is a variant of Cave applied to a 3.4.6.4; 3.42 6; 44 tiling. Rules Draw a single loop along the dashed lines that encloses some cells. Edges of this loop may not cross or share a ...
16
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1answer
387 views

Statue Park: Apollo 11

This is a Statue Park puzzle, made in honor of the 50th anniversary of the Apollo 11 mission. Rules of Statue Park: Shade some cells of the grid to form the given set of pieces. Pieces may be ...
15
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2answers
2k views

Virus Detected - Please execute anti-virus code

Virus Detected!!! Your computer, which is represented by the grid pictured, has been infected. The bugs are clearly marked. It's your job to inject your awesome anti-virus code in the proper computer ...
15
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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 ...
15
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1answer
349 views

Oriental HAISU - An unoriginal grid-deduction challenge

TheGreatEscaper comes up with several inventive (and original) grid-deduction genres, so I thought I'd try my hand at combining two of them. HAISU The rules are simple - draw a path from the O to ...
15
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2answers
905 views

25x25 slitherlink puzzle

Basic rules Form a loop using the dots (so, by joining orthogonally adjacent dots) such that a number N is surrounded by exactly N segments of the loop. Here's a tutorial puzzle and its unique ...
15
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1answer
287 views

Statue View: 2, 3, 5, 7

This is another Statue View puzzle. It's easily the hardest of the three I've made, so I recommend trying the other two as practice first. Rules of Statue View: Shade some cells of the grid to form ...
15
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2answers
513 views

Hitchhiker's guide to Scrabble

I was working at My God, it's full of stars! puzzle, when a sudden realisation came into my head: that I have a friend, who is also an astronaut, and that I have an appointment with him! We were ...
15
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1answer
1k views

Sum in A Sudoku

Color Blind version: Here's a sudoku puzzle with a twist! The numbers given in the squares are actually the sum of the numbers in that region. For example: 18= Sum of the numbers in the 4 yellow ...
15
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2answers
677 views

Tetromino Sudoku

An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids The grid below, when filled in, forms a valid Sudoku grid. It can also be filled in like a LITS (nuruomino) puzzle without the 1x4 ...
15
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1answer
559 views

Mini Ripple Effect puzzles

I enjoyed this puzzle so much that I created some mini versions of it for fun. I signed up to share them with everyone. The rules are the same: Each region with n cells contains all the numbers from 1 ...
14
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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 ...
14
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2answers
868 views

(1 of 11: Numberlink) What is Pyramid Cult's Favorite Activity?

Dear PSE users and moderators, I’m new here in PSE, but I really need your help. There was this person who gave me a black envelope consisting 10+1 pages of puzzles, and also a scribble saying: “Find ...
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5answers
1k views

A problem about Yin-Yang puzzles

In a Yin-Yang puzzle, one must fill every cell with either a black circle or a white circle according to the following rules: All cells with black circles form an edge-connected region. All cells ...
14
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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 ...
14
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3answers
377 views

Instructionless: Sieve of Eratosthenes

This is an instructionless puzzle: work out the rules and then solve the main puzzle. An example and its unique solution have been given to you, as well as two failed solutions with errors marked. ...
14
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2answers
645 views

A Trip to Ripple Islands

All aboard! All aboard! You have won an ALL-EXPENSES PAID TRIP to the magnificent Ripple Islands! Now, the only price of admission is to solve this little puzzle. It is a Ripple Effect puzzle based ...
14
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1answer
891 views

3D nonogram – Name the object

This is a 3D nonogram. The first five boxes represent the five layers of a $5\times5\times5$ cube, and the last box shows the enumerations for the Z-axis. (Note that 11 means two stretches of length ...
14
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2answers
963 views

Four-dimensional light bulbs

In reaction to Three-dimensional light bulbs - rules are same (almost) This is a four-dimensional Akari puzzle (also known as Light Up). The nine squares represent the layers of a $3\times3\...
14
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1answer
269 views

Broken Masyu: Quartered

Below is an 8x8 Masyu puzzle (rules can be found here), but the puzzle has been broken into four pieces! Can you put the pieces back together to make a proper Masyu puzzle with a unique solution? (The ...
14
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2answers
694 views

Trapezoids Compound Hidden Puzzle

UPDATE To refute Sconibulus's answer, I drafted a second puzzle with identical rules. 7 months ago, I released a collection of variations of an original puzzle called Trapezoids, but never mentioned ...
14
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1answer
378 views

HAISU with a twist

HAISU is a grid-deduction puzzle designed by this site's very own TheGreatEscaper. To quote them: HAISU is a portmanteau of three Japanese words - 'hairu', to enter, 'su', number, and 'hausu', an ...
14
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1answer
365 views

Hey! Wake Up! Look At This Grid Puzzle!

The grid is divided into rooms, though some are wibbly-wobbly weird-shaped. Hey, aren't these normally supposed to be blocks? What should the title of this puzzle really be? ...
14
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1answer
521 views

Why you shouldn't buy cheap puzzle books

Backstory contains important information, but nothing hidden. Also, tl;dr parts are bolded, but I can't guarantee I didn't forget bolding some part. Recently there's been a grid-deduction craze here ...
14
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1answer
329 views

Finding the hidden path (new grid puzzle concept?)

I was toying around with grid-based puzzles, and I can up with a format that I'm not sure exists yet, and from my testing leaves only one solution. (If it exists or is broken, please let me know so I ...
13
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1answer
235 views

Piece de Resistance - Jack in all Tags… But Master in All?

Jack in all Tags... But Master in All? This puzzle is part of the "Piece de Resistance" series. Go back to Part 1 (Ace) for the story.Ace Two Three Four Five Six Seven Eight Nine Ten Queen King... ...
13
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1answer
677 views

A bicolour masyu

This is a bicolour masyu puzzle. Instead of making one continuous loop, the goal is to make two separate loops, one blue and one red. The coloured circles must be used for the loop of the same colour, ...
13
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2answers
547 views

A spiral Ripple Effect puzzle

I'd say the rules to a ripple effect puzzle are best explained here. Anyways, I was making a bunch of Ripple Effects and decided to do a big one which didn't work out as I'd hoped, in that I needed ...
13
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1answer
667 views

Heyacrazy: Crosses

This is a Heyacrazy puzzle. Heyacrazy is an original genre, inspired by the "two border" rule of Heyawake and Heyawacky. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot ...
13
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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 ...
13
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1answer
556 views

Partiti : solve this new type of puzzle

These are puzzles similar to Kakuro, which is the creation of a friend of mine whom I met last year: Rules: Place one or more digits from 1 to 9 in arbitrary order in each empty cell, such that a ...