Figure 4.1.11.4[Black to move]

Black has a battery of bishop and queen trained on h2, a square adjacent to White’s king. How can he take advantage of this? Answer this question by playing through possible checks and captures in your mind’s eye, then methodically evaluating the board as it would look after the replies your opponent might make. Thus we begin by imagining Bxh2+. KxB would be impossible because Black’s queen still would bear down on h2; White would have to play his king to h1 or g2. Either move puts his king and queen on the same diagonal. Black thus looks for a pin with his light-squared bishop and finds Bc6, paralyzing White’s queen and winning it next move.