30 votes
Accepted

Alice and Bob invent a game

So building on kristinalustig's answer they are indeed playing The cards are assigned as follows Alice's first turn Bob's first turn In particular Alice's next move produces Bob's next move ...
  • 125k
29 votes

Shortest game of Monopoly

If you are trying to lose the game as quickly as possible then you can do it in 1 turn and 2 rolls of the dice. This is using the UK version as I'm not sure about the US one. Roll 1: Roll 2 (Because ...
28 votes
Accepted

Magic Maze Puzzle

Okay. THAT. WAS. INCREDIBLE! It took me two solid hours of work to solve and even longer to write and draw it all up here - hopefully it'll be worth it! To start us off, here is the final maze layout ...
  • 106k
27 votes
Accepted

Chess puzzle in which guarded pieces may not move

The answer:
24 votes
Accepted

What's the maximum number of pegs you can leave on a 15-hole triangular peg solitaire?

It can be done in jumps. Here is the solution: If you start with the hole elsewhere, you need more moves to reach an end position. Here are all the optimal end positions for each case, but without ...
22 votes

Battleship- Best Next Move

The "best" move for this puzzle is the one most likely to hit the ship in one shot, as the puzzle doesn't allow for further follow up shots. There are 23 possible positions for that ship, and 68 ...
  • 1,587
22 votes
Accepted

A game of red and black

The game is and the result is
  • 140k
21 votes
Accepted

Scrabble Impossibilities

The word was... And the reason you couldn't play the more common variant was...
  • 140k
20 votes
Accepted

Let's continue our Monopoly game

It is currently: because All that means it is now the
  • 7,706
19 votes

A Boyfriend's Mysterious Message

  • 474
19 votes
Accepted

Four free rooks for checkmate

First rook is placed at any of Second rook is placed The third rook is placed And then the fourth rook A crappy example game below:
  • 18.5k
18 votes
Accepted

Battleship- Best Next Move

D5 covers 4 locations D8 covers 3 F2 covers 2 H2 covers 1 G6 covers 0 E5 is the best; it covers 5 locations.
  • 2,939
17 votes
Accepted

8-queen puzzle on its head

On my puzzle website there is an old puzzle called Hoo-Doo which is essentially this same puzzle. Some other board sizes:
17 votes
Accepted

But She Don't Care

These board-gamers are playing: The board at the end of the game looks like this: Who wins the game? A final few Easter Eggs:
  • 106k
16 votes

Alice and Bob invent a game

I spent quite a while working on this yesterday and today. I only have a partial answer. I started with the assumption that I chose this assumption because: Given this assumption, I tried: However:...
  • 3,082
16 votes
Accepted

Chain Puzzle: Tabletop Games #10 – Risky Finale

The clue answers: Sorted by group (and given in text form): And when you take the given pair of letters, and read those pairs of letters in clue order, it spells out the message: The full journey ...
  • 140k
15 votes
Accepted

Queen chasing a knight (chess pieces)

For the updated version, I'll assume that after the placement of the pieces, the queen moves first. (Otherwise the knight could arrange things so that the queen is captured on the first move.) In ...
  • 1,917
15 votes

Clear board in Othello (Generalisation)

Here is one way you could begin to prove that the board can be cleared for all values of $m$ and $n$. Proof by induction. [incomplete] Case 1: $k = 1$ Here we take k = 1 to mean the smallest ...
  • 1,008
15 votes
Accepted

Chain Puzzle: Tabletop Games #08 - Targui, or not Targui

From the facts about the first grid My first guess of the genre was Naturally, the next step would be It is not very hard, if we focus on the number 5: Therefore, Now to the second grid. With ...
  • 10.9k
14 votes

Queen chasing a knight (chess pieces)

The queen can always win. If the queen goes first, obviously it will win (just take the knight). If the knight goes first, there are only 2 places to go (mirrored, so effectively the same): ...
  • 9,780
13 votes
Accepted

Clear board in Othello

Yes, I found this video on YouTube that has this "perfect game". Terrible music by the way https://www.youtube.com/watch?v=prWG1OFgVqg
  • 11.1k
13 votes
Accepted

Least amount of moves is required

Using a computer to attempt to beat my original solution I found some Here is one: I reduced the search space by not allowing stones to moves to (although they can jump via) the spots marked with an ...
13 votes
Accepted

Capturing The Shadow King

OK, I barely made it with 10 moves, but it seems pretty hard to prove this is optimal (and I suspect the answer may be lower). The last move you make is Rh8, which will be the mate.
  • 6,874
13 votes
Accepted

Unfinished Snakes and Ladders

The other guys already got the answer. (Maybe not with completely airtight arguments, but nevertheless.) The explanations would be a lot easier to follow if they had pictures, so here's one: Legend: ...
  • 69.5k
13 votes

Advantage, Black!

This should do it: White is in zugzwang, so black has
  • 69.5k
12 votes
Accepted

Find the shortest chess game with 18 queens?

This is known as the "18 Queens Problem". I know of this well-known solution by Friedrich Burchard & Friedrich Hariu, published in the German magazine feenschach issue #33 in 1976 on ...
  • 12.7k
12 votes
Accepted

Color Configuration 3x3 board

This kind of puzzle is commonly referred to as "lights out", after a board game by that name. I googled that phrase and came upon a solver at http://www.ueda.info.waseda.ac.jp/~n-kato/lightsout/. So ...
  • 3,040
12 votes
Accepted

Othello - Most number of legal moves in a given turn

The upper bound limit is likely to be quite a bit lower than 60. For the purposes of this I will assume that you are WHITE. In order for you to have a valid move in Othello, you need a line formed ...
  • 10.6k
12 votes
Accepted

Monte Carlo Chess

I initially gave a slightly rambling stream-of-consciousness answer, which I have preserved below in case anyone prefers that. Here is a slightly slicker one. (It is the same argument, just possibly ...

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