2. Kd3 Kd7 3. Kc4 Kc6 taking the opposition (see below). However, the white king can reach a key square (b5) by going on the other side of the pawn: 1. Kc2! Ke7 2. Kb3 Kd6 3. Kb4 Kc6 4. Kc4 Opposition, and Black is in zugzwang. 4...Kd6 5. Kb5 or 4... Kb6 5. Kd5 and the white king has occupied a key square and has a winning position. Opposition The second concept needed is opposition – when two kings face each other with only one square in between, the side with the move may have to move the king away and allow the opposing king to advance. The other king has the opposition. However, Averbakh pointed out that the opposition is a means to an end; the end is penetration to a key square. If you can penetrate without the opposition, then do so. In this diagram, White should seize a key square by playing: 1. Kc5 and moving to a key square on the next move (e.g. 1...Kd7 2.Kb6). Taking the opposition by 1.Ke4 draws (as do any other moves). Rules If the pawn is not a rook pawn some rules apply: Rule 1: With one exception, if the black king can get to the square in front of the pawn, or the square in front of that (which are key squares), he draws. The reason is that if the black king alternates between those two squares, he can keep the white king from getting to a key square. The exception is the position in the diagram, and only if White is to move, because of 1. d7 Ke7 Black was in zugzwang. 2. Kc7 followed by 3. d8=Q Otherwise, if the black king stays on one of those two squares, he keeps the white king from occupying a key square. Rule 2: White wins if at least any two of the following conditions are met: (a) the white king is in front of the pawn (b) white has the opposition (c) the white king is on the sixth rank. In positions in which fewer than two of the conditions are met, it may or may not be possible to get to a position meeting at least two of the conditions, depending on the position of the pieces and who is to move. In such positions, if the attacker can get to a position that meets two conditions,