Top Questions

7 votes
1 answer
1k views

You're the NSA, trying to decrypt a message between two friends

13 votes
2 answers
2k views

A Game of Phones

42 votes
1 answer
12k views

The Beale Papers

0 votes
1 answer
20 views

Build a slanted pyramid with ten L-shaped blocks

2 votes
3 answers
148 views

Write a sentence that is true in one language and false in another

1 vote
2 answers
115 views

The Omniscient Vegetable

7 votes
0 answers
44 views

A Crabby Sudoku

6 votes
1 answer
207 views

Make a square table top with the minimal needed amount of straight cuts

-2 votes
0 answers
76 views

An Alien Lands - where? [closed]

3 votes
1 answer
108 views

Pole, rope, and chasm

12 votes
3 answers
489 views

Transforming letters into words

8 votes
0 answers
426 views

Use your fingers!

7 votes
1 answer
1k views

Name and solution of puzzle to rotate all arrows to same direction

10 votes
2 answers
353 views

Make a square table top with six (or fewer) pieces

1 vote
0 answers
90 views

Last chess game

10 votes
0 answers
586 views
+500

A Drink and a Game

7 votes
1 answer
122 views

A pandigital alphametic

4 votes
1 answer
202 views

Dishonest dungeon staff

3 votes
4 answers
1k views

The Three Mystery People- An Actual Mystery

7 votes
0 answers
307 views

A simple puzzle with no happy endings

3 votes
5 answers
1k views

Professor Rackbrane: Count the triangles

18 votes
1 answer
1k views

The Challenge Square

7 votes
3 answers
7k views

Adjusting wrongly assembled Rubik's Cube

3 votes
1 answer
84 views

Rubik's 4x4x4 Cube - Is there a "pair of moves" view of parity algorithms?

2 votes
2 answers
839 views

2759, 4248, 1152,?

7 votes
1 answer
267 views

Choose and snooze

12 votes
0 answers
277 views

Catch the flag!

28 votes
1 answer
2k views

Where is the large cook promotion?

29 votes
4 answers
3k views

Melissa's Numbers

6 votes
5 answers
630 views

Circles crossing every cell of an NxN grid

6 votes
3 answers
297 views

Cryptic Division 10: Printer's Player for a Football Club in Tasmania

4 votes
1 answer
209 views

Ernie and the Kzijekistanian Coup

3 votes
2 answers
283 views

JMO + JMO + JMO = IMO alphametic

25 votes
2 answers
1k views

A Trivial Pursuit #25: Meta-Analysis

9 votes
3 answers
1k views

Alternative solutions to a Michael Rabin puzzle

8 votes
1 answer
310 views

Creation of two (Opposites are opposite)

17 votes
2 answers
1k views

A small board-puzzle

16 votes
4 answers
924 views

Make the three products equal and as large as possible

11 votes
1 answer
917 views

A mysterious importance

4 votes
1 answer
119 views

Enigma (Oxyd based) game, 0.92 -3, level #4 "Seed Puzzle"

8 votes
1 answer
477 views

Spider Solitaire Puzzle - Can You Help Joe Bloggs Achieve His Goal?

13 votes
1 answer
509 views

Plumbing Issues

44 votes
8 answers
7k views

How many Chess Pieces are needed to control every square on the board? No Piece Restriction

3 votes
2 answers
438 views

Three related things

10 votes
1 answer
1k views

Cover me, I'm going in!

20 votes
2 answers
885 views

Masyu: Four Colours

5 votes
2 answers
511 views

Connecting the unconnected


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