Rules Arbiter
Chess
Ask about the rules. The Arbiter answers from this rulebook and tells you which pages to check.
Common questions
Can I castle if my king was in check earlier, or if my rook is attacked?
Sources:
Yes to both. A check earlier in the game does not take the right away; what counts is whether the king and that rook have moved. If you got out of the check by moving the king, castling is gone for good; if you blocked the check or captured the checking piece, you may still castle later.At the moment you castle, the king must not be in check, and neither the square it crosses nor the square it lands on may be attacked. The rook is not bound by that rule: it may be under attack, and when castling on the queen's side it may pass over an attacked square.
All squares between the king and the rook must still be empty. On the queen's side that includes the square next to the rook, which the king itself never crosses.
When exactly can I capture en passant?
Sources:
Only right after your opponent moves a pawn two squares from its starting square and it lands directly beside one of your pawns. Your pawn has to stand on its fifth row, counted from your side of the board.You capture diagonally forward onto the square the enemy pawn passed over, as if it had moved only one square, and remove that pawn from the board.
The right lasts one move. If you make any other move first, you can no longer take that pawn en passant, even if it is still standing beside yours.
My pawn reached the last row. Should I always take a queen?
Sources:
You choose freely between a queen, rook, bishop and knight of your colour, and the promotion is part of the same move. It does not matter which pieces you have lost, so a second or third queen is allowed.A queen is usually the strongest choice, since it moves along rows, columns and diagonals. Only a knight, though, moves in an L shape, so a new knight can attack squares, and give check, that a queen on the same square could not reach.
Pick a rook or a bishop when a new queen would leave your opponent with no legal move while not in check: that is stalemate, and the game ends at once in a draw. A weaker piece that still leaves them a move keeps the game going.
When is a game drawn, and do I have to claim it?
Sources:
Some draws happen on their own: stalemate, when the player to move has no legal move and is not in check, and a position in which nobody can checkmate, such as king against king or king and knight against king.Others have to be claimed by the player to move: a threefold repetition of the same position with the same player to move, or fifty moves by each player without a pawn move or a capture. If nobody claims, play goes on until the position appears for the fifth time or seventy-five such moves pass; either one ends the game as a draw automatically.
The players can also agree to a draw, and running out of time is a loss only when the opponent could still checkmate; otherwise it is a draw as well.
The Arbiter is a language model. It answers from this rulebook and shows the pages it used.