As we have seen in the previous lesson the Queen is one of the pieces that is often involved in these double attacks. Most of the time it is relatively easy to find a square from which the Queen attacks two other pieces. But a double attack isn’t limited to an attack on pieces.

In this tutorial the following targets are distinguished:

• King: Checking the King is different from all other moves, because the King has to be moved out of check 
• Piece: One or both of the targets can be a Piece. 
• Square: Even a square can be attacked. 
• pawn: Winning a pawn may be enough to win the game. 

Let’s look at two examples:

		It is White’s turn to move. In such an endgame the Queen is almost always able to capture the Knight by means of a double attack at the King and the Knight. The move 1.Qe4 looks like a double attack but fails, because of 1…Nf5. Do you see the right move for White? After 1.Qg1 White will win the Knight.
		The next diagram on the left is an example of a double attack on a square and a Piece. The involved square is h8 and the attacked Piece is the Knight on a7. White attacks both targets with 1.Qd4. Even in the situation that Black has an additional Rook on h8 this is called an attack on a square and a piece, because only the most important targets are mentioned. And in this case it doesn’t matter that White is attacking a Rook. Why is this square so important that Black has to give his Knight? White threatens mate at h8.

So in order to find all the possible Queen forks you have to search for all the undefended Pieces (or pawns), all the possibilities to place the King in check and all the squares that can be used to mate the King.

If you manage to find a fork attacking both the King as well as such a square you have found a mate in two.

This series of chess lessons continues with the Elimination of the Defender.