The game of chess

Resources

Special Rules

En Passant

"En passant" is a pawn's special move, the name comes from French and it literally describes an ambush maneuvre. It can be performed by an advanced pawn against a defending pawn moving two squares ahead on an adjacent column. The maneuvre can only be performed immediately after the defending pawn has moved two squares in advance to reach the fourth line and it consists of the advanced pawn moving one square diagonally onto the defending pawn's column thereby capturing the defending pawn.

Castling

Castling is another special move of the game. It allows moving two pieces during the same turn. It comes in two flavours. Castle Kingside is when the King moves two squares to the right and the right hand side rook moves onto the bishop's starting position. Castle Queenside is when the king moves two squares to the left and the left hand side rook moves into the Queen's starting position.
Castling can only be performed under certain conditions:

1. It must be the first move the king makes during the game.
2. It must be the first move the rook makes during the game.
3. No other pieces must be on the path either the king or rook must take in order to achieve the required positioning.
4. None of the squares along the king's path can be under attack by the enemy pieces.