Special moves
Three moves that don't follow the normal rules — but you need to know them.
Castling — kingside
The king moves two squares toward the rook, and the rook jumps over to the other side. Both pieces move in one turn — the only time two pieces move at once.
You can only castle if the king and rook haven't moved yet, and the squares between them are empty.
Castling — queenside
Castling works the other way too. The king goes two squares toward the a-file rook, and the rook jumps over to the other side.
You can't castle if the king is in check, or if it would pass through or land on an attacked square.
Pawn promotion
When a pawn reaches the other end of the board, it transforms into any piece you choose. You pick one of these four:
Almost everyone picks the queen — it's the most powerful piece. But sometimes a knight is the better choice!