The usual position in this chapter starts with the kernel of a discovery in place at the outset. Perhaps the target needed to be created or improved, or maybe a good threat needed to be found or made for the unmasking knight; but the idea was in place from the start and easily triggered trains of thought about how it might be made to work. We now consider some cases where the kernel is not in place at the start—where it first must be built with an initial move that creates the familiar masking pattern while also forcing a reply by your opponent. The forced move itself often adds one of the necessary elements for a discovered attack, usually by moving a target into place. Then follows the unmasking move that attacks two points in the enemy camp at once, requiring one of them to be forfeited. Visually your task is to become alert to moves that put one of your pieces (in these cases a knight) into the path of another, and then to go through the familiar process of imagining how the discovery might be perfected.

In the position on the left, assume Black just made a capture with his knight on b5; now the natural tendency for White would be to play QxN. Don’t do it. Always examine your checks to see where, if anyplace, they lead. Here White has the interesting Qc8+. You see that this forces Black’s king to h7, and that White then runs out of good ways to hunt the king down. The crucial thing is not to give up then, and instead to back up and see what patterns would be in place. White would have formed the kernel of a discovery: his knight now masks his queen’s path toward Black’s queen on g4. White can unmask the attack with check—Nf8+ (perfectly safe, as opposed to Nf6+)—and then he has QxQ after Black moves the king from h7.

The trick to the position, of course, lies in seeing the kernel of a discovery when it isn’t on the board in front of you but will be created by a move or series of them that you are contemplating. The prospect of a discovered attack might not occur to you in the original position; it might come to mind only once you experiment with Qc8+ and observe what it does. When you think of a move that puts one of your pieces in line with another, pause to consider the tactical side-effects for you—or for your opponent. On the other hand, the idea is more likely to become apparent if you can perceive it visually; so study the appearance of this position.

Notice, by the way, an amusing mating possibility if Black blunders into it: 1. Qc8+, Kh7; 2. Nf8+, Kg8; 3. QxQ, KxN; 4. Qc8#—a back rank mate made possible by Black’s silliness in allowing his king to get trapped behind his pawns and rook with no defender.