# Questions tagged [50-move-rule]

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### Why does the 75 move rule apply when the game have a forced checkmate?

In this position for example White has a forced checkmate in 549: [FEN "1n1k4/6Q1/5KP1/8/7b/1r6/8/8 w - - 0 1"] How is it fair to terminate the game before White could ever force the win?
• 159
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### How does this problem relate to the 50 & 75 move rules?

[Title "Draw - T. Volet. Ded. M. Caillaud & N. Plaksin. 1st Prize Rex Multiplex, 1983"] [FEN "n4K2/b1pprppp/1p2p3/2p5/N1P3P1/BkP1P3/1P2PPP1/3N1BR1 w - - 0 1"] I have an ...
• 509
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### When was the last time a chess rule was modified?

I am talking about legal moves and draws, I mean when does every rule about draw and legal move change, like when does en passant, castling change, when does fivefold repetition threefold repetition ...
• 159
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### chess.com dosn't apply fide rule?

I was talking about the draw set, in FIDE 9.3 The game is drawn, upon a correct claim by a player having the move, if: 9.3.2 the last 50 moves by each player have been completed without the movement ...
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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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### Can Loss by Checkmate be Avoided by Invoking the 50-Move Rule Immediately After the 100th Half-Move?

The FIDE Laws of Chess state the 50-move rule as follows: 9.3 The game is drawn, upon a correct claim by a player having the move, if: 9.3.1 he/she indicates his/her move, which cannot be ...
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### What happens in a King-Rook vs King-Bishop with a perfect play in a no pawn endgame?

Suppose both the kings are left in a fairly neutral positions with just rook at one side and a bishop at the other side. What is the outcome if both the sides play correctly? Can a side with only ...
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### Practical play in KRPvKQ central pseudo-fortresses?

A rook and a pawn sometimes draw against a queen, if a proper fortress can be set up. These are possible to learn to defend, and it's also possible to learn how to attack these with a queen when the ...
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### Are engines impaired by the 50-move rule?

Are we missing too much from the 50-move rule implementation to engines, whether HCE (Hand-crafted evaluation) or/and NN (Neural Network)? We know that certain endgames are a win without the rule. ...
• 51
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### What is the need for repetition rules given the 50 & 75 move rules?

Given the existence of the (optional) 50-move rule and the (mandatory) 75-move rule, are the (optional) threefold-repetition rule and the (mandatory) fivefold-repetition strictly necessary? Do the ...
• 359
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### A question about draw detection in chess engines

Let us look at this position. [FEN "4k3/8/8/p1p1p1p1/P1P1P1P1/8/8/4K3 w - - 0 1"] This is obviously a draw. Analyzing this with the Stockfish engine says that it is a balanced position. ...
1 vote
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### EXTENDED New Year's Math Riddle: 5-fold repetition & 75-move rules

This puzzle extends Rewan Demontay's New Year Math Riddle. Rewan asked (essentially): if the players co-operate, what's the largest number of times a given diagram can occur in a game before reaching ...
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### A 50-move-rule claim turned out to be incorrect - can the arbiter punish me?

I claimed a 50-move draw, but my claim turned out to be incorrect. Can the arbiter punish me by increasing the opponent's time or reducing mine?
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### Is there a position where it's possible to claim a draw by both the 50 moves and threefold repetition rules?

It doesn't matter which one the player chooses in that situation, but I'm wondering whether someone can come up with a game where this holds true for at least one move.
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### Can a KB vs. KB endgame be declared drawn if a checkmate can occur and the 50-moves-rule doesn't apply in a Blitz game?

Bishop and King vs Bishop and King, with opposite-colored bishops, is usually a draw unless a serious blunder happens. [FEN "8/8/8/3b4/8/7k/8/6BK w - - 0 1"] What is the requirement for an ...
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### How long can a player hold off a draw by the 50-move rule?

Going by rules strictly about the board state, how long can a player theoretically hold off a draw by the 50-move rule? White will play as long as possible, and not want to lose. Black will claim a ...
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1 vote
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### Chess Problem: Reset The 50-Move Rule!

While chess problems and such are usually meant for Puzzling Stack Exchange, I thought that this one should be an exception since it’s more relevant IMHO. Resetting the 50-move rule, i.e. restart the ...
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### What is the longest tablebase win that includes draw rules?

It has been asked the longest mate that includes draw rules is, and it is known what the longest tablebase mate is. However, what is the longest tablebase mate, i.e. 7 pieces or less, that accounts ...
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### 50-move rule: only the last 50 or any consecutive 50?

Suppose that, as a result of White's move, there have now been 100 single-moves (50 full moves) since the most recent pawn move or capture. White didn't claim a draw because they're going for the win. ...
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### Does anyone have a version of the 50x50 article by Nikita Plaksin?

In 1979, Nikita M. Plaksin published a reportedly fascinating article containing 50 problems all related to the 50 moves rule. Unfortunately I can't find it anywhere, the only links that I could find ...
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### Identify a problem where a potentially winning move draws because of the 50 move rule

I'm trying to recall a particular chess problem. It's related to retrograde analysis. All what I can remember is this: it's an endgame where there is only one way to reach the position, and during ...
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### Is it OK to look at the list of played moves during the game to determine the status of the 50 move rule?

There are some positions in which you need to know how many moves have been played without pawn move or capture. For example: [FEN "1R5K/8/8/8/8/8/7R/k7 w - - 98 1000"] (1R5K/8/8/8/8/8/7R/k7 w - - ...
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### If both sides move at random, but legally, then how many games will be a win for White or Black, if not a draw? [duplicate]

I would guess that very few games, in terms of percentage, will end with a draw. The winning percentage will be roughly the same for both White and Black.
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### Why is there a 50-move rule and a 75-move rule?

Logically, if 75 moves have been played, 50 moves would've also been played. This sounds ridiculous. It is like saying "I would buy this book if it cost under \$60 and it costs under \$40". So,...
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### On the feasibility of a KBN-K mate within 50 moves using a particular method

Prove that it is possible, from any starting KBN-K position, to accomplish the mate by manoeuvering to arrive at key positions from a well-known method or strategy whilst the losing king actively ...
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### Why doesn't castling reset the 50 moves rule?

Capturing a piece or moving a pawn irreversibly changes the state of the game and thus resets the counter for the 50-move rule. Since castling irreversible changes the state of the game too, it seems ...
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### What's the maximum number of moves that can result in a threefold repetition from an arbitrary position?

Assume that the fifty-move rule does not require a player to claim a draw. Instead, the game is automatically declared a draw if no pawns have been moved and no pieces have been captured in the last ...
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### 50-move rule: FIDE wording seems weird

FIDE rules seem to say that I have to claim draw (3-repetition and 50-move) before I actually touch/move my piece. And if I move my piece first, and then claim the draw, it doesn't count. 1) Is this ...
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### What is the order of actions in chess under FIDE rules?

Reading some recent posts about the 50 move rule made me realize that I've never seen an explicit order of actions for chess. By way of comparison, the order of actions in Monopoly is given here: (1) ...
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### Claiming a 50-move draw with a mating move [duplicate]

Under FIDE law 9.3.1, a player to move may claim a 50-move draw by writing down the intended 50th move and making the claim. Supposing this claim is otherwise valid; if the move would checkmate then ...
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### Is a forced draw by 50 moves possible with Bishop and Knight endgame?

Except for the variations where there is a capture or fork possible for the defending side, is a position possible where this kind of endgame will last more than 50 moves? Is somewhere a calculation ...
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### Simltaneous checkmate and draw claim on the 50th move [duplicate]

This question is for aspiring rules lawyers. The FIDE's new laws of chess, effective Jan. 1, 2018, patch ambiguities and other subtle problems. I like the new laws. When it comes to game mechanics, I ...
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### How do UCI chess engines handle the 50-move or threefold repetition rules when playing against other engines?

I'm working on an engine that implements the UCI protocol that is intended to play against other engines. Since the UCI protocol has no commands for offering or accepting draws, how does this work ...
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### What is the source of the house-rule 18-moves?

In my area, most kids including me grew up with a very popular house-rule: After all the pieces of either of the players are removed besides the king, the opposing player has 18 moves to checkmate him....
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### Does checkmate over ride 50-move rule?

If a move reaches the 50-move rule and gives checkmate at the same time, does the checkmate take priority over the draw?
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### The 50 Move Rule

Can the fifty move counter be increased after white's move? I thought that it could only be increased if both white and then black had not moved a pawn nor captured a piece that qualified for a whole ...
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### Chess endgame database+50-move rule=potential error?

Are there any examples of positions where usage of the endgame tablebase gives an incorrect evaluation, due to the ignoring of the 50-move rule? At the moment I am not sure if endgame tablebases ...
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### Proof of irreversibility of 50 move rule

I recently edited the Wikipedia article 50 Move Rule as follows: The rationale for this rule is that pawn moves and captures are the only '''irreversible''' types of moves. That is, after ...
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### What are the hardest pawnless endgames that go over the 50-move rule?

I know two pawnless endgames that go over the 50-move rule. King and 2 Bishops vs. King and Knight = 70 moves average. King, Rook and Bishop vs. King and 2 Knights = 200 move average. What others ...
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### Is the 50-move rule ever used in grandmaster games?

The 50-move rule states that if no capture or pawn move occurs for 50 consecutive moves, then either player may claim a draw. It seems like the 50-move rule is never truly necessary to determine that ...
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### Has the 50 move rule been used in serious games?

There are a lot of questions about the 50-move rule; details on how to claim the draw, why the number 50, etc... But the most interesting question seems to be whether the rule has ever been applied ...
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### I'm confused about the 50-move rule

A player may claim a draw after 50 moves-does this mean 25 moves by each player, which results 50, or 50 moves by each player, which results 100?
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### With only a king left, how many moves remaining until a draw?

I am a beginner in chess. If I have only a king left, how many moves does my opponent have to mate me?