# 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.

216 questions
621 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 ...
145 views

### You Sign Me Right Round

This is a 9x9 grid, with a sign in the center cell like shown. You can add signs to this grid one at a time following these rules: Each sign placed must point to the next sign placed Placed signs ...
572 views

### 3D Crossword, Cryptic, Statue View & Maze

The following image depicts the layers of a $5\times5\times5$ cube. Using 3-dimensional thinking, can you find the way out of the cube? Empty version with no crossword numbers Empty version ...
744 views

### Very tricky nonogram - where to go next?

I've become somewhat addicted to Simon Tatham's "Pattern" (nonogram) puzzles recently. I thought I was becoming fairly adept with them, but this unusually difficult one has me stumped. I've got as far ...
360 views

### Masyu puzzles with many circles

The rules of Masyu: Make a single loop with lines passing through the centers of cells, horizontally or vertically. The loop never crosses itself, branches off, or goes through the same cell ...
194 views

### Vertical and Horizontal Bars - An Instructionless Puzzle

Study the 2 examples given on the left and solve the puzzle on the right! The solution for each puzzle can be uniquely determined.
167 views

### Solve the pattern! (game)

Okay, so this is based off of https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/pattern.html And, my cousin made a random pattern and gave it for me to solve. Unfortunately, the logic is ...
330 views

### Statue View: Tetrominoes

This is a Statue View puzzle, an original invention combining two logic puzzle genres: Statue Park and Canal View. Rules of Statue View: Shade some cells of the grid to form the given set of pieces. ...
229 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 ...
232 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 ...
465 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 ...
251 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. ...
256 views

### Statue Park: Five

This is a Statue Park puzzle (originally constructed for the 2019 24-Hour Puzzle Championship, as part of a Tarot card themed set -- no prizes for guessing which rank this puzzle was). Rules of ...
344 views

### Untitled, for Now

As you step into the gallery, you notice an interesting piece of art hanging on the wall. "I like the piece, but what's with the title?" you ask the docent. "I'm used to obscure titles in modern art, ...
1k views

### Introducing Domidoku!

Come one, come all! Come see the new type of logic puzzle, the Domidoku! Here's a sample for all to try! The process is simple! First you solve the Sudoku and then you solve the Dominosa! ...
990 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 ...
195 views

### SafeCracker #2 - The Mission Continues

Thanks to an alert StackE user, we were able to get the first safe open. Mission Details This next safe is in a former employee's house. He is gone for now, so we have no time to spare. We weren't ...
4k views

### Gerrymandering Puzzle - Rig the Election

The following graphic is a map of the country Mathlandia: You are currently running for reelection, but the polls aren't exactly in your favor. Each square in this grid is a county. Counties with a ...
224 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: ...
902 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. ...
225 views

### Can someone solve this kakuro?

Can someone solve this? Please tell me how you did it. Source: Puzzle Page app
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 ...
537 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 ...
3k views

### My God, it's full of stars!

An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids My dear friend, unknown to us, may have relocated again. He sent me imagery and constellation maps indicating that a distant red ...
267 views

### Modified Intersection Puzzle

This is a slightly modified version of the Intersection Puzzle introduced by user477343 here. In this case, you are given a $7 \times 8$ grid with circles and boxes provided in some of the cells. ...
214 views

### Square Spin #1: Sun and Moon

Defining Square Spin Lets play a game! The aim of this game is to transform one image into another using the least amount of moves possible. Here is what a move consists of: ...
2k views

### One 'double agent' two-step on a waltzing floor

I'm in a jam – cornered I am! – No clue 'bout where to go Here's what went down, a pretty gown Some wine, a French chateau She whispered underneath her breath "Come dance with me and ...
297 views

### Swap — A Puzzle I Created

This puzzle is called Swap. Let's find out why! Suppose you are given a random $\rm N\times N$ matrix (grid) with all the integers from $1$ to $\rm N^2$ each belonging in every grid square (a.k.a. ...
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 ...
490 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 ...
742 views

### How will you save Mike?

A direct hint: this question. Question starts from here: You are Dr. Nathaniel - a renowned archaeologist, and involved in a research about an ancient site. But, there is only one problem - the ...
340 views

### What in this world is she trying to say?

I happened to meet one of my friends after about a couple of years. Obviously we both were very happy, but still, she didn't leave her habit of challenging me to decipher what she was saying. I ...
188 views

### Triple (Almost) Gaps - Schezo's Edition

Today (Mar 16) is Schezo's birthday! Happy birthday my little creeper boi~ <3 Clarifications: $C$ may or may not be equal to $1$. The set actually tells you that at least one of $\{C,M,N,P,R,T\}$ ...
221 views

### Albrecht Durer Inspired Magic Square

A magic square is an n-dimensional matrix in which each row, column, and main diagonal sums to the same 'magic number' (denoted by s). A normal magic square uses each of the numbers from 1 to n ...
534 views

### Distance Puzzle

The rules are: 1. Draw two circles (O) in the empty cells in every row and column. 2. The numbers in the black cells indicate the space between the 2 circles in the black cells' row or column, in ...
946 views

### Sum in a sudoku with sum total of 15 and 45

I have created a sudoku puzzle with the following restrictions: Each row and column sum to $45$. Each row and column in the nine $3$ by $3$ sub-grids sum to $15$. Is such a sudoku unique?...
265 views

### Stuck in 6x6 skyscraper puzzle

I don't know how to continue, can anyone tell me which next number am I able to add? Here is the puzzle (there are clues at edges), and below are possibilities. Feel free to tell me if I made mistake, ...
109 views

### Slitherlink failure - help needed

I have player "slitherlink" (or "Loopy" as it is sometimes called) generally on a 20x25 grid, so I don't finish too quickly. However I have come across a puzzle (seed was not recorded), that MUST be ...
73 views

### Does it exist a way to solve visually by using a grid or to find the truth among a set of five people telling different statements?

I am having problems with trying to solve this riddle therefore I am looking for help. The situation is as follows: At a semiconductor laboratory in Hsinchu a security guard caught five ...
171 views

### Fixing a Binairo Mistake

The rules of Binairo are simple: 1) Each row and column must have an equal number of black and white circles. 2) There can be no horizontal/vertical line of three like-color circles. Starting ...
116 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 ...
340 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 "...
251 views

### Word Rectangle #2

As with my previous puzzle, this is an unfinished word rectangle: Can you fill in the blanks? When completed, every row will contain a common English word with five letters, and every column will ...
663 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 ...
239 views

### An unknown Cryptogram

I would like to say : vyycd gow mcgr uuey
2k views

### GRID-THIRTY-SIX

Solve 36 puzzles (or more) to find the final 6 letter answer.
2k views

### I am an island (ysaujdiolkiun)

An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids I received an envelope containing two drawings and no return address. I would recognize that handwriting anywhere - my dear friend ...
100 views

### Heyawake - how to continue?

Can you help me find the next move. (The cells marked with dots must be white).