# 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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### Who proposed that S stand for knight in English chess problem notation?

A small barrier to entry to the chess problem world is that knights are denoted "S" rather than "N". This confusing usage comes over as snooty and precious, but unfortunately we ...
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### Longest checkmates with the biggest material disadvantages in "open" positions?

We can ask a question: What are the longest checkmates with the biggest material disadvantages? What, approximately, is the function between length of the checkmate and possible size of the material ...
118 views

### Most delaying moves before checkmate

Consider a position where if was player A's turn, they could make a series of moves ("the mating sequence") with forced mate. However, it is player B's turn, and they can make a series of &...
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### Difficulty of problems for different rating levels

For club players, it is pretty well-known that certain types of problems are harder than others. Of course, mate in 4 is usually harder than mate in 1, but I am talking more about things like the ...
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### What are the longest "golden sequences" in chess? (sacrificial middlegame attacks)

Initially, I was interested in the question "what are the longest sacrificial middlegame attacks?" ([Kasparov's Immortal] is one of the most famous sacrificial middlegame attacks). But this ...
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### Is there a mate in two moves for white?

How is this a mate in two? I can't see it. [fen "k4r2/1rQ1b1p1/2Rp1n2/1p2p2p/P7/1P3PBq/5P1P/4K2R w - - 0 1"]
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### How many queens can check a king without it being checkmate (with no other pieces on the board)?

I am going to write an autobiographical story. The motive is therapeutic. I suffered abuse from my father, and at the age of 20, I developed delusional disorder; the psychosis lasted for 20 years, and ...
3k views

### Most mate options after 6 moves

Found this construction problem from '83 and liked it. I don't know the best solution (yet), and maybe you can top it anyway. Consider the (help) "game" 1.e4 a6 2.Bc4 a5 3.Qh5 a4. Now White ...
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### The 50 moves game

Play the longest game from the starting position such that each move resets the 50 move rule (i.e. is a pawn move or a capture). As I see it, each pawn quartet on adjacent lines has maximally 4+6+6+6 ...
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### Longest *fairy* chess problem

Longest orthodox chess problem One for the specialists. In the newest SCHWALBE I saw some titanic lengths (one problem had 2^59+2^57+3 ~ 10^18 moves!) As you see, this scales with O(2^(n^2)), where n ...
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### Max percentage of mating pieces

In the newest SCHWALBE, positions are given where any piece on the board can give a check (any being surprisingly high). A quick dabbling seems to prove that it is not possible that any piece can mate....
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### Questions about legality of last move

Question for FIDE Arbiters and similar knowledgeable folk... FIDE Law Article 5.1.1 The game is won by the player who has checkmated his/her opponent’s king. This immediately ends the game, provided ...
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### Most imbalanced (but equal) chess position?

I recently found this beautiful position, Position 11 where White sacrifices a bunch of material and then there are a bunch of crazy variations that all end in draws. For example this variation which ...
186 views

### What position has the most possible moves that all lead to being checkmated?

Inspired by this position from a game I played. [FEN "r1b2rk1/p2p1p1p/2qb1PpQ/2p1p3/2p1P3/5N2/PPnP2PP/R1B2RK1 b - - 0 1"] Black has almost all their pieces, is not in check, and can make 27 ...
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### Is there a real version of the chess puzzle from The Yiddish Policeman's Union? If not - can it be made?

I will preface this by saying that the following contains a spoiler for Michael Chabon's The Yiddish Policeman's Union, so tread carefully. Chess features heavily in the book and a major plot point is ...
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### Searching games by chess positions

I have a somewhat weird question that is only indirectly related to chess. I am trying to solve a chess-related puzzle in which I have to find games played by Soviet chess players based on positions. ...
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### A puzzle where you must find the mate in 3 solution but avoid mate in 2 and mate in 1 solutions?

I want to see if a puzzle could exist where you must avoid finding mate in 1 or 2 but just find the mate in 3 solution. This is not subjective it is a hard math problem to make a move that forces mate ...
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### Good chess puzzle that involves queen running around the board?

Basically title. Ideally not too difficult or too many steps, but if you have any good puzzles where the queen traverses across the board. Thanks in advance!
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### Checkmate in ω² moves with finitely many pieces

The post Checkmate in ω moves? has inspired a lot of discussion and mathematical research into positions on an infinite chessboard where white can mate in a transfinite amount of moves. The current ...
267 views

### Mate-in-N problems where N scales indefinitely with board size

Motivation - Long range mating patterns This question is inspired by my recent interest in infinite chess and the post on MathOverflow Checkmate in ω moves?. Since my chess endgame skills are quite ...
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### Grimshaw in practical (OTB) game

Does anybody know of an example of the Grimshaw-Theme being used in a practical game? For the Nowotny there are several examples (e.g. Navara-Dergatschova, Ordix, 2007) and for the Plachutta there is ...
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### Are there any hard mate-in-2 problems?

I'm interested to know if there are any particularly challenging mate-in-2 problems. Since the second move will be essentially forced, the problem essentially comes down to 1 move. Typically, the ...
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### Longest sequence of moves where White's number of available moves does not change

There are challenges for the longest sequence of moves in which white's available moves increase or decrease. This challenge is for the longest sequence of moves (from the opening position) in which ...
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### What is the longest sequence of increasing White moves with only White pieces?

Inspired by a comment by @Evargalo on this question, I ponder how long a sequence can last where each turn, White has more available moves than the previous turn, in a situation with only White pieces ...
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### Is there a Chess 960 position in which White's moves can be decreased to zero without check?

Inspired by this question, koedem proved that, from the starting position, White's legal move amount can be decreased sequentially from 20 to 0 in 20 moves. However, doing so required some checks. I ...
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### Longest sequence of moves where white's number of available moves decreases

An easier version of this White has 20 available moves at the start of the game (from the standard position). After 1.h3 h5, white has 19 available moves. (The h pawn has lost the ability to move two ...
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### Longest sequence of moves where number of available moves increases

White has 20 available moves at the start of the game. After 1.a4 e5, white has 21 available moves. (The rook has gained 2 moves, while the pawn has lost 1). What is the longest sequence of moves ...
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1 vote
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### Roundtrips with no shortcuts

In the picture, you see the longest roundtrip of a rook such that there are no "shortcuts" - imagine the target squares are given, then at each square you have exactly two other given ...
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### Move forcing opponent to checkmate in response

I was wondering if there was a move so bad in chess that if you played it the only move your opponent could do was checkmate you back, through blocking your piece or through moving the king. It would ...
252 views

### Longest sequence of unique legal moves for one player, always in check and ending in checkmate

I recently played a bullet game, in which I thought I was in checkmate, but then realized I had one legal move, this then repeated again and again 6 times until ultimately I was in checkmate. I share ...
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### What is the maximum total number of piece points possible on the board?

Maximum number of non-pawn pieces on the board notes how to get the maximum number of non-pawn pieces on the board. But what about the maximum number of points possible? It seems like this starts ...
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### Legal positions with one color to move only?

Most positions in chess can be reached with both black or white to move. Some positions are only legal with one color to move. One such position is the starting position, which famously can't be ...
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### A little Silvester puzzle

A regular game has been played where White still has all 16 pieces. White promoted only a single pawn, and not to queen. In the final position all 16 pieces of White have (at least) one mating move. ...
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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? ...
1 vote
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### Piece Peace Puzzle

Place the whole army of White and the black king on the board, such that no piece is attacked or defended. (Obviously you must use double pawns.) That's fairly easy, so tie breaker will be how many ...
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### Position where neither player can force an *exact* outcome

There are three possible outcomes of a game of chess: white wins, black wins, or the players draw. Typically, we consider a win better than a draw, so when we say "white can force a draw" ...
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### Do any unique proof games feature an en-passant capture?

Most positions that could be reached, in a specified number of moves, after an en passant capture could be reached just as well without one, suggesting that such positions could not occur in unique ...
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### Open problems in chess involving maximum material imbalances

I am posting the present question since here Very unbalanced Chess Positions I have introduced three open problems (i.e., the third one, the fourth one, and the sixth one from the above), regarding ...
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### Longest sequence of unique series moves

Clearly a spawnoff of the preceding question, but far easier to analyze, and maybe helping a bit to solve that one too. Take the starting position, remove all black pieces to simplify and now make ...
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### A fun game (for problem composers, mostly...)

A game leading to a given position is called a proof game. Of course any proof game can be prepended with 1.Nf3 Nf6 2.Ng1 Ng8, so we defined a shortest proof game as, duh, the shortest possible proof ...
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### Minimal forced checkmate

A forced checkmate is a situation in which the player whose turn it is has only legal moves which put the other player in checkmate. I’m searching for the minimal forced checkmate (the smallest amount ...
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### Where does the term “cook” originate?

What is the origin of the term “cooked” for a chess problem with an additional, unintended solution?
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### Fastest stalemate in Duck Chess

Seeing the meteoric rise in popularity of Duck Chess (full rules), I'd like to ask how to stalemate the fastest (from the starting position) in this variant, because the stalemated player wins here. ...
189 views

### How many more squares can you attack?

(Inspired by this cool problem) Let’s say it’s White to move. Let A = the number of squares currently attacked by White, and B = the number of squares attacked by White after White’s next move. What ...
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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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### Maximum futile material (in illegal position) neither winning nor forcing stalemate

We assume standard (P1BN3R5Q8) value (personally I prefer 1,3,3,4.5,9 but so there). To get a drawn position with maximum material difference, not caring about that it's illegal, we just have to ...
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### Position where neither player can force a win and neither player can force a draw

One sometimes sees the claim that in every chess position, either White has a forced win, or Black has a forced win, or both players can force a draw. While this claim is "morally" correct, ...
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### Pinned piece chain

How long a "Pinned piece chain" can you make? Here a "Pinned piece chain" is a chain of pieces where each is pinned by the last. Here for example is a chain of length 3. The ...
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