Touch-move rule the player touches his rook at the same time as touching the king, he must castle with that rook if it is legal to do so. If the player completes a two-square king move without touching a rook, the player must move the correct rook accordingly if castling on that side is legal. Otherwise, the move must be withdrawn and another king move made. When a pawn is moved to its eighth , once the player takes his hand off the pawn, a different move of the pawn can no longer be substituted. However, the move is not complete until
Block (chess) chess can involve placing a piece between two opponent's pieces where one of those pieces is protecting the other, or they are both protecting each other. This chess tactic can be called "interference". When the attack cannot be ignored, the attacking player has the initiative. The defending player may be able to acquire the initiative by blocking and attacking at the same time, by attacking an undefended attacker with the blocking piece, with a discovered attack, or when the block is also a check or a cross-check. Block (chess) A block is a defensive tactic in chess in response to