# Questions tagged [problems]

Chess problems consist of a board position and a task. Most ask for a line of play that mates black in a set amount of moves, or a combination that results in a winning position. Many other types exist, including, but not limited to, construction tasks for various positions and proof games that have numerous goals, selfmates, helpmates, and retrograde analysis. Tournaments and championships exist for composing of original problems and for speed-solving.

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### How fast can checkmate occur by just moving the king?

How short can a game be in which (after the first move) one player moves only their king, and yet checkmates their opponent? This is assuming that the players cooperate, i.e. this is a kind of "...
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### How is this position possible in a normal game of chess?

A friend of mine gave me this problem. It goes like this. In a normal game of chess, the white player checks the black's king with a rook and a bishop as in the following image. 8/8/8/8/8/7k/8/...
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### When was it possible for a player's king to be attacked by 3 of the opponent's pieces?

According to the current FIDE Laws of Chess: 3.9.1 The king is said to be 'in check' if it is attacked by one or more of the opponent's pieces, even if such pieces are constrained from moving to ...
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### A mysterious mate in one

Here's a question that's a little off the usual format, but problem questions like this have been done before and are on topic, so here we go! Question: Can you find the mysterious mate in one? The ...
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### What move requires the greatest number of moves before it could be played in a game?

The move e2e4 could be played on move 1. (One half-move) The move e7xd6 could be played no earlier than by black on move 3 (6 half-moves). What move(s) has the latest "earliest possible move it ...
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### Can you solve this unique chess problem of white's two queens vs black's six rooks?

[FEN "3Q4/7Q/3rp3/2rkr3/2rrr3/7K/8/8 w - - 0 1"] I found this interesting and unique chess problem online, on the internet. Disclaimer: This is not necessarily a position from a game. It's ...
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### What is the highest number of different mates in 1 you can have in one (legal) position?

A friend and I yesterday asked ourselves what the highest number of possible mates in a (legal) position is. We were able to come up with the following position which has a total of 76 unique mates in ...
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### Endgame problem: How to avoid stalemate and win?

I'm stuck on this problem a friend shared with me recently, with barely any pieces left and apparently white is able to force a win but I've been hitting a wall with everything I've tried so far, as ...
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### Can all 64 squares be attacked or defended by the eight pieces?

Can you place the eight (non-pawn) pieces of one color on an otherwise empty chess board, such that every square (including the squares that pieces are on), is attacked / defended? This is a problem ...
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### Stalemate situation with all pieces on the board

Suppose all the pieces are on the board. Does there exist a position such that A) one of the players can't make any move (a stalemate)? B) neither player can make any move (a double stalemate)?
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### How can I prevent checkmate in this position?

It is White's turn to move. How can White avoid a checkmate? [FEN "8/1kpP2q1/1p2P1p1/1P3pP1/5p1K/5P2/6P1/R7 w - - 0 1"]
• 307
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### Longest sequence of mutually forced moves

In this position, the black move 1. ... Qc3 results in two consecutive forced moves, Kxc3 and Ke7: 2rkr3/2p5/2q5/8/8/8/3KP3/3R4 b - - 0 1 1... Qc3 2. Kxc3 Ke7 What is the longest sequence of ...
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### From the start of the game what is the longest possible series of consecutive white moves where white can do those moves no matter what black does?

From the start of the game what is the longest possible series of consecutive white moves where white can do those moves no matter what black does? So I want the longest list of moves white can do ...
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### Why underpromote in this KNNP-KR endgame?

In the position below, I'm promoting my pawn. The app says promoting to a Queen is incorrect, but a Rook is correct? In this setup it doesn't make sense. [FEN "8/1P6/3N4/8/8/3k4/r7/4KN2 w - - 0 1"] ...
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### Least number of moves to achieve a complete switchover of nonpawns in starting setup

[fen "RNBQKBNR/8/8/pppppppp/PPPPPPPP/8/8/rnbqkbnr w - - 0 1"] During a comp, my friend an I had a team kill and we decided to make this position(legally) before drawing. Then we continued to find ...
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### Please help solve this endgame problem posed by a friend

[FEN "5K2/k7/4P1p1/8/8/8/4b3/8 w - - 0 1"] A friend of mine is challenging me to find a solution. It’s White to play and DRAW.
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### Another Unusual Mate in One

Here is another mate-in-one of my own i.e. a not quite usual one... [title "Mate in one"] [FEN "3b4/R3P3/2kPR1n1/P1p1n3/4K1p1/2Nr4/5p2/1b6 w KQkq - 0 1"] Imagine, you ...
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### Is there any position where not promoting (illegally) would be the best move?

Is there any position, where moving a pawn to last rank but not promoting it to any piece would be the best move? By the way, I know this is an illegal move. Assume it is legal. Edit: Now we have a ...
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### Why do chess puzzles need a unique solution?

Why do chess puzzles need a unique solution? This is different from real games, where such situations do occur, but more frequently, there are multiple avenues to success. Contrary to what one might ...
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### What is the solution to this mate in 2 puzzle?

What could be the answer to it?
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### White to play and checkmate in two moves

It’s White to play and checkmate in two moves. This puzzle was created by Frank Healey, and published in 5 Family Herald on 7/17/1858. 7R/1B1N4/8/3r4/1K2k3/8/5Q2/8 w - - 0 1
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### What is the longest known sequence of forced moves leading to a checkmate for one side?

By forced move, it is meant that the player has only one legal move. [fen "7k/q5Q1/p4PPK/6PP/8/5P2/8/8 b - - 0 1"] 1... Qxg7+ 2. fxg7+ Kg8 3. f4 a5 4. f5 a4 5. f6 a3 6. f7# Above is an example with ...
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### Basic "mate in one move" puzzle - what am I missing?

I am extremely new to chess and have been working through some "mate in one" problems on chesspuzzles.com for practice. This one has me very confused though: The stated answer is: But why? ...
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### Maximum number of queens possible

I was thinking about what the maximum number of queens can be on the board after only legal moves. The theoretical upper bound would be 18, the original 2 queens plus 16 promoted pawns. However, to ...
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### Can you solve this chess problem of king and pawn against all opposing pieces?

[FEN "8/8/8/2p5/1pp5/brpp4/qpprpK1P/1nkbn3 w - - 0 1"] I found this interesting and unique chess problem online. Disclaimer: This is not a plausible position from a game, however it is ...
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### What is the theoretical limit for the number of consecutive checks?

The known record for the longest sequence of consecutive checks (i.e. white checks, then black checks on the next move, white checks next, and so on) in a legal position without promoted pieces, is 37....
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### What is the origin of this breakthrough combination?

If you've spent enough time in the world of chess, it's not unlikely that you've come across the following position, with white to move and win, or an essentially identical one. You'll see plenty of ...
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### What is the theoretical maximal material difference of a dead draw which is not a stalemate?

I have noticed the following example, which should be a dead draw: I am wondering what is the theoretical material difference of a dead draw which is not a stalemate? (I am not asking about agreed ...
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### Is the position in this trick question reachable?

I found this trick question on r/Anarchy chess: White to move, mate in two. [FEN "2R2RK/6PP/5P/3PN/P/1pQ3p/n1p1qbp/5brk w - - 0 1"] [StartFlipped "1"] The trick is that But is ...
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### Is there a double-forced mate position?

A usual forced mate position is where the winning player can play in a way that ensures checkmate, no matter what (legal) moves the opponent makes (unless the game ends due to a non-play reason, i.e. ...
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### Is the chess problem a dead form?

Or, to ask the question a bit less opinionatedly, "what new ideas have been introduced in chess problems over the last 20 years?" I imagine many problems have been composed in that time, but it seems ...
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### Fastest possible checkmate by en passant

En passant is somewhat of a rare move in chess. Checkmating by en passant, however, is an even rarer occurrence. But suppose both sides had the same goal to help cause a checkmate to their opponent ...
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### Chess Problem Database with PGN or FEN

Is there a database of chess problems that have the game or positions PGN and or FEN?
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### Can White avoid a loss in this endgame study by Lazar?

This is the position with White to move. This was created by Lazar in 1935 according to Susan Polgar in a Chess Daily News article from 5/27/2008. [FEN "8/3P4/3b4/8/8/1p2k2p/1Pp4P/2K5 w - - 0 1&...
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### THE longest problem ever (much longer than the mere 549 mover...)

The "Fireside Book of Chess" by I. Chernev and F. Reinfeld includes the following diagram [fen "3nk3/3NN3/3PP3/3BB3/3PP3/3PP3/3PP3/2RQKR2 w - - 0 1"] Composed by J.N. Babson for ...
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### How do you solve vague mate in two problems?

I am a big fan of solving mate in N problems and believe they help tremendously with i.e. visualization. The only issue I seem to face in certain problems are when they are very vague. For example ...
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### Prove that White is not allowed to castle here

A friend recently gave me the following weird chess problem to solve. I'm afraid that I'm struggling to see the key idea that would ultimately count as proof. From the position, intuitively speaking, ...
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### How much material is needed to force the capture of a lone queen (for example in horde chess)?

In horde chess, the following starting position is used: [FEN "rnbqkbnr/pppppppp/8/1PP2PP1/PPPPPPPP/PPPPPPPP/PPPPPPPP/PPPPPPPP w - - 0 1"] The goal of White is to checkmate Black; the goal ...
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### Maximum possible movement in a turn

I've read that for any position, there are on average approximately 35 possible moves. But what's the maximum number of possible moves for a position?
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### Why are capturing key moves "frowned upon"?

Wikipedia's article on Babson tasks says: However, Yarosh's problem has a small flaw: the key is a capture, something which is generally frowned upon in problems. (The "key" of a chess ...
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### Can you solve this queen + 3 pawns vs bishop + 3 pawns chess problem?

[FEN "7k/8/8/8/6p1/4QpPb/5PpP/6K1 w - - 0 1"] I found this interesting and unique chess problem online while surfing on the internet. Disclaimer: This is not necessarily a position from a ...
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### What moves solve this mate in 2?

It’s White to move and mate in 2 moves. [FEN "7r/1p3Q1p/2q5/3bk3/1Q2p3/2P5/r2P2PP/2KR4 w - - 0 1"]
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### Fastest King vs King endgame

What is the fastest possible game that ends in a King vs King endgame? Please post a game and tell me the number of half-moves you've achieved. By some simple logic, I can prove that this number is ...
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### Can white win in this almost 20 year old puzzle?

It's White to move-can they force a win?. The left bottom is a1 as usual. [FEN "4k2r/6p1/p4pKb/p2N3p/p7/p5Q1/p1n5/qrn5 w - - 9 9"] Note for people who saw an earlier version: the position ...
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### Beautiful retrograde analysis problem by Alexsey A. Troitsky

I saw this beautiful, subtle & accessible problem a couple of days ago, and wanted to share it with you folks. (It's by the ground-breaking endgame theorist who e.g. invented the "Troitsky line" ...
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### Is the "Pawn Box" possible in standard chess?

Is it possible to create a "pawn box" as shown below (using legal moves and the help of black) in standard chess? The positions don't need to be exactly as shown, and there can be more pieces on the ...
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### Arrange 5 non-attacking knights on a 5x5 toroidal board

The celebrated British mathematician and lover of public transport, Simon Norton, passed in 2019. He was the subject of a wonderful biography. He was not a particular fan of chess, but here is a tiny ...
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### Maximum number of pieces on board in dead position

It is possible in a chess game to have a dead position in which both players have all eight pawns, one bishop, and a king--20 pieces total. If the two players' pawns are interlocked in "zig-zag" ...
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### What is the shortest possible game with 18 queens?

This question demonstrates a game in which all 16 pawns promote for a total of 18 queens on the board. It takes 80 moves... What is the shortest sequence of moves that achieves this goal?
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