Chess
Overview
Chess is a two-player strategy board game played on an 8×8 grid. White moves first, and players alternate turns. The goal is to checkmate the opponent's king.
Pieces and Movement
| Piece | Symbol | Movement |
|---|
| King (K) | ♔♚ | One square in any direction |
| Queen (Q) | ♕♛ | Any number of squares in any direction |
| Rook (R) | ♖♜ | Any number of squares horizontally or vertically |
| Bishop (B) | ♗♝ | Any number of squares diagonally |
| Knight (N) | ♘♞ | "L" shape: 2+1 squares, can jump over pieces |
| Pawn (P) | ♙♟ | Forward one square (two from starting position); captures diagonally |
Special Moves
Castling
The king moves two squares toward a rook, and that rook jumps to the other side of the king. Requirements:
- Neither king nor rook has moved previously
- No pieces between them
- King is not in check, and does not pass through or land on an attacked square
En Passant
If a pawn advances two squares from its starting position and lands beside an opponent's pawn, the opponent may capture it as if it had moved only one square. This capture must be made immediately.
Pawn Promotion
When a pawn reaches the opposite end of the board, it must be promoted to a queen, rook, bishop, or knight.
Winning and Drawing
- Checkmate: A player wins by putting the opponent's king in check with no legal escape.
- Stalemate: If a player has no legal moves and is not in check, the game is a draw.
- Threefold Repetition: If the same position occurs three times, the game is drawn.
- 50-Move Rule: If 50 moves pass with no pawn move or capture, the game is drawn.
- Insufficient Material: K vs K, K+B vs K, K+N vs K, or K+B vs K+B (same-colored bishops) are all draws.
Variant: Chess960 (Fischer Random)
The starting position of the back rank is randomized (960 possible arrangements), with two constraints:
- Bishops must be on opposite-colored squares
- The king must be between the two rooks
Castling rules are adapted for the randomized positions.