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1500 questions
32
votes
1 answer
Puzzlegrid: 5 levels
Those are the warmups. Here's the real challenge.
And yes, it is uniquely solvable.
Wen1now
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32
votes
3 answers
Speak the Name of the Father! - Name the lord of the gods so that he may yet survive the theomachy
Our father was the first of our kind, though his many children and grandchildren rule over billions, caging them.
I am a liberator, and my father shelters those who travel through water.
Father once bled silver till there was none left to bleed,…
Travis Don Kindred
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- 2
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32
votes
6 answers
Find 7 solutions
You have three flat pieces, as shown:
Arrange them flat, without overlap, such that the shape formed by the black parts is congruent to the shape formed by the white parts. Rotation and reflection are allowed.
Find at least 7 distinct solutions.
If…
TheGreatEscaper
- 11,946
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32
votes
6 answers
Will a greedy algorithm solve Tatham's Flood?
I was just investigating some of the puzzles on Simon Tatham's website, and came across Flood, in which we start with an $n\times n$ grid of cells each of which is filled with one of $k$ predetermined colours, and (quoting the game…
Rand al'Thor
- 116,845
- 28
- 322
- 627
32
votes
5 answers
An animal out of matchsticks
Ok, I widely failed my two latest matchsticks puzzles, so here's another attempt, part of the 22nd Fortnightly Topic Challenge.
As you can see, you have in front of you eleven matchsticks forming the word zoo:
You have to move one matchstick, and…
IAmInPLS
- 11,471
- 4
- 43
- 112
32
votes
18 answers
Riddle-Yet-Another-Riddle!
Let us tell you a story about nothing but us.
Unbleached sometimes, sometimes not, that's what they discuss!
We were fabricated by some type, and that type had a needless lane.
Magical we might be, the future probably, we shall never go in…
Techidiot
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32
votes
3 answers
How many squares can 4 queens control?
Though there is no strict mathematical proof, it has been shown via brute-force that no arrangement of 4 or fewer queens can control every square on a standard 8x8 chessboard.
So, out of the 64 squares on an 8x8 chessboard, what is the maximum…
Unsigned
- 471
- 5
- 11
32
votes
13 answers
You will have to pray!
This riddle is so easy that I already have created another one. Just in case.
Anyway, please avoid wild guesses.
For sure I am queer
and out of place
Are you still here?
Go start the chase
But always remember
in the first place
stacks are…
Avigrail
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- 66
32
votes
4 answers
Sum other numbers
Begin with a flagrantly erroneous summation
and a woefully vacant substitution table.
234
+ 5 Digit 2 3 4 5 6 7 8
------- Substitute digit _ _ _ _ _ …
humn
- 21,899
- 4
- 60
- 161
32
votes
14 answers
15 Balls Sorting
This is a variant of 15 Balls Weighing.
You have 15 balls of 15 different weights, but the weights are so similar you can't tell them apart by feel. The balls are also identical by any other sense you might try, and cannot be marked, marred, or…
user3294068
- 7,498
- 23
- 32
32
votes
10 answers
100 Prisoners and a clock
There are 100 prisoners who are given a chance at freedom. The prisoners are randomly picked to visit a room where there is only a nonfunctional wall clock with a knob for manually changing the time.
The rules are as follows:
The prisoners are to…
user26522
32
votes
4 answers
A Letter from the Past
It has been quite a while since your first assignment as a P.U.Z.Z.L.E. agent. Most of your tasks weren't even half that exciting and since your boss is currently on vacation, your most important task right now is to beat the ceiling dart high…
Sleafar
- 18,027
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32
votes
4 answers
Breaking the record
There is a record whose value is expressed by a natural number. (The value is strictly discrete, not only continuous and then rounded to a natural number.) However, after the record is once established, any other person to topple the previous…
Widdershins
- 423
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- 7
32
votes
12 answers
Where do all the doors lead to?
You are walking in a hallway and find a door.
You decide to enter the room. The door closes behind you, the room suddenly becomes dark and starts spinning.
You fall on the floor in the middle of the room, totally disoriented. You have no idea which…
Maria Ivanova
- 7,856
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- 81
32
votes
3 answers
Alphametic as protest
This is my (constructive) way of protesting the new sandbox for riddles.
It's a simple alphametic.
You know the rules.
Each letter is a unique digit.
The leading digits cannot be 0 (zero).
If you offer a solution, please add your reasoning.
…
Marius
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