# 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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### Spiral Stumper Series: Instructionless Puzzle

Spiral Stumper Series is a $5$-puzzles series taken from the Final Round of a local (national) contest, KPK, which has been ended recently and authored by me. The theme is spiral and each puzzle is ...
440 views

### (5 of 11: Slitherlink) What is Pyramid Cult's Favorite Person?

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 ...
273 views

### Domatic lights puzzle - an introduction

Rules: Each white hex must contain either a red, green or blue light bulb. Light bulbs of the same color cannot be in neighboring hexes. Each white hex must be lit by all three colors of light (...
185 views

### What Goes Round (Begriddled logic puzzle)

Join adjacent numbers in the below grid to reveal the hidden content. The rules are: 1: Join all pairs of vertically and horizontally adjacent numbers that are the same. 2: Join all pairs of ...
365 views

### Square Spin #4: Rude Awakening

Square Spin History: #1>#2>#3>#4 New Rule This puzzle introduces a new square type: Lonely squares (Ly) Lonely squares This type of square contains a box and it is the exact opposite of ...
678 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? ...
314 views

### Unusual Sudoku Puzzle

Find the solution to this Sudoku puzzle. The only problem is there aren't any normal Sudoku clues. Instead there are only some cryptic clues. What is the solution and how does the puzzle work? Edit: ...
562 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 ...
276 views

### Another follow the path of relation through the grid

Inspired by Galen's series of puzzles...there is a relation between rectilinear-adjacent squares such that there is a unique rectilinear path from the top-left corner of the grid down to the bottom-...
394 views

### (10 of 11: Nurikabe) What is Pyramid Cult's Favorite Topic?

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 ...
304 views

### Grid puzzle solutions

I have a simple grid puzzle: Example: | X | Y | X | | Y | X | Y | | Y | X | Y | The move is defined as a row or a column move. So when you move one cell, ...
198 views

### I know I should solve this Masyu… But… How should I make this puzzle more colorful?

I know I should solve this Nurikabe variant... I know I should shade all Masyu circles... I know I should not let $2 \times 2$ unshaded squares appeared... I know I should solve this Masyu... ...
217 views

### Nurikabe minicubes: the Headache, the Panache, the Apache

These are three-dimensional Nurikabe puzzles. In each case, the four squares represent the layers of a $4\times4\times4$ cube. The goal is to shade some cells in each layer so that the resulting space ...
204 views

### Heyacrazy: Dissection

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is solved, ...
439 views

### A Sincere Nurikabe Puzzle

So here's a standard Nurikabe puzzle. I'll be using the final (solved) grid for my upcoming local puzzle competition logo as it will spell the abbreviation of the competition name. So, what does it ...
515 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, ...
265 views

### 3D nonogram – The one-thousander

This is a three-dimensional nonogram. The first ten squares depict the layers of a $10\times10\times10$ cube. The final square gives the enumerations for the Z-axis, top to bottom. Some rules: If a ...
219 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
373 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 ...
1k views

### Fill this 5x5 number grid incrementally, either by moving two boxes diagonally or moving three boxes in a row or column

One day, a friend has shown me a 5 by 5 grid, challenging me to fill it with numbers from 1 to 25. Obviously, it is not simple because there are some rules: The number 1 is placed in the center of ...
512 views

### Skeleton sudoku, the second

I've already set one skeleton Sudoku. Here's a rather harder one. (Nonetheless, it should be within the realms of what can be done by hand; I solved it manually myself to verify that there was only ...
512 views

### Revenge of the 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 relevant order. The solutions to the ...
335 views

### Mixed-breeds are puzzles too!

This is a three-dimensional mixed-breed puzzle. The five squares depict the five layers of a $5\times5\times5$ cube. The goal is to solve the odd-numbered layers as yajilin and even-numbered layers as ...
274 views

### Yajisan-Kazusan: Diagonal Arrows

This is a Yajisan-Kazusan puzzle. Rules of Yajisan-Kazusan: Several numbered arrows are given in the grid. Shade some cells so that: no two shaded cells are adjacent unshaded cells form ...
502 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 ...
795 views

### 13-by-13 SIKAKU puzzle

A SIKAKU puzzle consists of a square or rectangular grid in which some of the cells contain a one or two digit number. To complete the puzzle, a Solver must divide the puzzle into a number of ...
224 views

### Heyacrazy: Forks

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is solved, ...
235 views

### Restoring 3D Tetromino Puzzle

You won't believe this. I worked all night to make a new 3D tetromino puzzle, and just as I was about to save the final version there was a power outage! Now I can't remember what the final clues were ...
190 views

### 4 More Meander Puzzles

My previous set of meander puzzles was fairly well-received, so I decided to make some more. If you didn't see the first set of meander puzzles, the instructions can be found here. Here they are: ...
65 views

### Chain Puzzle: Tabletop Games #05 - It's Yahtzee, Jim, but not as we know it

This is the fifth Chain Puzzle in the Tabletop Games series, in which all puzzles are themed around board games, card games, tile games, and the like. The answer to this puzzle is a thematic word or ...
250 views

### Whirlwind of the Square Sudoku Table

. . . | . . . | . . . 6 . . | . . 1 | . 2 . . . . | . . . | . . . ---------+---------+-------- . . 7 | . . . | . . . . . . | . . . | . . . . . . | . . . | . ...
217 views

### Puzzle of the day - Sudoku Rossini

The arrows outside the grid indicate that the nearest three digits in the corresponding direction are in ascending or descending order (the highest number is always in the direction of the arrow). All ...
451 views

### 3D Statue Park: U shapes

This is a three-dimensional Statue Park puzzle.1 The five squares in the below image depict the five levels of a $4\times4\times5$ cuboid. The goal is to fit inside it the four three-dimensional ...
274 views

### Quick Ripple Effect Puzzle: $70$ Empty Cells

Ripple Effect (taken from Nikoli) The areas divided by bold lines are called "rooms". Fill in all empty cells with numbers under the following rules. Each room contains consecutive numbers ...
891 views

### Fill numbers to the star shaped puzzle

Fill in all the blank circle with numbers 1 to 6, so : Each lines of 6 circles, contains 6 different numbers. Each corner (consist of 3 greens circle) sums to 11. There is only 1 unique solution.
390 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, ...
401 views

### Organically Overhauling my Occupation

After secretly assassinating a wealthy doctor in the countryside, I found myself with surplus funds. Naturally, the best possible investment is investing in oneself, so I boarded a plane and went out ...
293 views

### 3D Nonogram - Spinoff of the Reboot

This puzzle is inspired by recent 3D nonogram puzzles by Jafe and Omega Krypton. Check those out if you want, but they are not required to understand this puzzle. This 3D nonogram has clues with two ...
340 views

### Quick Slitherlink Puzzles: KPK and 123

Slitherlink (taken from Nikoli) Connect adjacent dots with vertical or horizontal lines to make a single loop. The numbers indicate how many lines surround it, while empty cells may be ...
220 views

### Friday's Dominosa Problem

Dominosa is a logic puzzle with a similar feel to Sudoku, and I've recently added it to Donimoes, my collection of domino puzzles and games. Given a grid of numbers, you have to lay out the dominoes ...
401 views

### Akari: Another Light

Rules (taken from Nikoli): Place light bulbs (circles) according to the following rules. Light bulbs may be placed in any of the white squares, the number in the square shows how many light ...
357 views

### Toroidal Heyacrazy: Rainstorm

This is a Toroidal Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle ...
708 views

### IBaNTsJTtStPMP! #2

IBaNTsJTtStPMP means "I'm Bad at Naming Things, so Just Try to Solve this Patterned Masyu Puzzle!". The original Masyu rules apply. Make a single loop with lines passing through the ...
748 views

### Can you solve this nurikabe puzzle?

Here's a nurikabe for you. Let's see who can solve it first.
259 views

### Nurikabe: Sixes

This is a Nurikabe puzzle. The goal is to paint some cells black so that the resulting grid satisfies the rules1 of Nurikabe: Numbered cells are white. White cells are divided into regions, all of ...
185 views

### Quick Nurikabe Puzzle: $4$s

Nurikabe (taken from Nikoli) Fill in the cells with black under the following rules. You cannot fill in cells containing numbers. A number tells the number of continuous (adjacently) white ...
426 views

### Heyacrazy: Empty Space

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is solved, ...
504 views

### Tribute to Eugene Varshavsky bwahhahahahahahahah

Each cell in the lower-right 9x9 grid must contain a positive integer or be left blank. Numbers on the outside of the grid indicate the sums of one or more adjacent digits in that row or column, in ...