Castling Castling Castling is a move in the game of chess involving a player's king and either of the player's original rooks. It is the only move in chess in which a player moves two pieces in the same move, and it is the only move aside from the knight's move where a piece can be said to "jump over" another. Castling consists of moving the king two squares towards a rook on the player's first , then moving the rook to the square over which the king crossed. Castling may only be done if the king has never moved, the
First-move advantage in chess whimsically suggests 17.h4!?, forcing Black to be the one to break the symmetry. 17... Re8! Rowson notes that this is a useful waiting move, covering e7, which needs protection in some lines, and possibly supporting an eventual ...e5 (see Black's twenty-second move). White cannot copy it, since after 18.Re1 Nxf2 Black would win a pawn. 18. Be3 Nxe5! 19. dxe5 Rc6! Rowson notes that with his more active pieces, "It looks like Black has some initiative." If now 20.Nxd5, Bxe5 "is at least equal for Black". 20. Nxb5 Bxe5! 20...Nxf2? 21.Qxd5! wins. 21. Nd4 Bxd4 22. Bxd4 e5 Rowson writes,