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Questions tagged [illegal-move]

A move that doesn't respect the rules of chess.

A move that doesn't respect the rules of chess.

61 questions
97
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12 answers

Why is it illegal to castle with both hands?

I was watching the match between Ian Nepomniachtchi vs Hikaru Nakamura and Nakamura used both hands to castle. Why is it illegal to castle using both hands? What's wrong with that?
tah
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3 answers

Can a piece pinned to my king put the opponent's king in check?

I was playing a game with a friend online. A situation came up where he put me in check with his bishop, and I moved my rook to block it. His king was on the g file and my rook was on g2. The website said he was in check. [fen…
ken
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2 answers

I made an illegal move. What happens?

Especially in blitz or bullet games, it is possible that a player makes an illegal move, for example castles through check. If the opponent does notice the illegal move, then as far as I know the first player is obliged to make a legal move with…
Armen Tsirunyan
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2 answers

Is taking the opponent's king an illegal move?

In competition blitz games, making an illegal move and then pressing the clock forfeits the game if the opponent claims the illegal move as long as they do not make a new move, as a new move would void the previous illegal move according to FIDE…
Pep
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27
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4 answers

Why is castling through and out of check prohibited?

Why is castling disallowed when the king is in check or when the square the rook will be placed on is under attack? What is the rationale behind this ruling?
Alexandros
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25
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6 answers

Are there any illegal positions that are difficult to spot?

I have a question and I'm sorry if it sounds very uninformed, I'm not a professional chess player so my interest is mere curiosity. I was wondering if there are examples of illegal positions that require more than a superficial look at the…
seawalker
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1 answer

The illegal moves in Carlsen-Inarkiev

In the first round of the World Blitz Championship in Riyadh. Magnus Carlsen played Ernesto Inarkiev and the game ended strangely. [FEN ""] [StartPly "53"] [Event "World Blitz Championship"] [Site "Riyadh KSA"] [Date "2017-12-29"] [Round "1"] [White…
user1583209
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7 answers

How do you know when a FEN position is legal?

I am making a research on validating FEN positions, at first it is obvious the basics things to look for, such as checking if there are only two kings and making sure the rows or columns add up and those kinds of things. But what other checks should…
ajax333221
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1 answer

Why is it illegal to move into check?

In chess, it is against the rules to move into check, or to not move out of check. But why? Obviously, if you went against this rule, you'd immediately lose. But it seems strange to make it illegal to lose in such a way. Is there a reason for this…
Winston Ewert
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5 answers

Hitting the clock without moving

In an official blitz game, what happens if a player hits a chess clock without making a move? I believe that making an illegal move in a blitz game is an automatic loss. But does this count as an illegal move because my opponent didn't really make a…
MyronL
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11
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1 answer

Series of illegal moves in check

This question falls under FIDE rules (USCF answers/comments welcome). If I make an illegal move leaving myself and my opponent in check, hit the clock and my opponent misses it and then continues play and hits their clock what happens? So for…
Aaron
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4 answers

Can I hover my finger over a chess piece without touching it in a major chess tournament?

Noob question: I am aware of the no-touch rule, but can I point or hover my finger over a chess piece in a major tournament? To clarify, let's say it's my turn and I am thinking about which piece to move, and part of my thinking process is to move…
Aevil1
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4 answers

Outcome of a game in case of an illegal checkmate

Suppose that, in an amateur rapid play tournament (where supervision is inappropriate), the following position appears: [fen "5K2/8/1q6/1N1k4/8/8/8/2R1R3 w - - 1 1"] 1. Re5+? Qc5+? {illegal} 2. Rxc5# The players do not agree on the result of the…
Alexandre Aksenov
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9
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2 answers

What "double moves" are sometimes considered legal?

As we know, castling is a legal "double move," where two pieces are moved at once. But in my country, Indonesia, in my childhood, the opening below was an 'assumed legal' double move to counter 1.e4 and similar openings. [FEN…
Ahmad Azwar Anas
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9
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2 answers

Touch a piece and then claim opponent's previous move was illegal

In a last round tie between 2 players fighting for top seed in a competition, here is what happened. White had 18 seconds on his clock and black had 26 seconds. Black was winning. At move 56, black made a pawn push which exposed his king to a check…
oziomajnr
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