Bishop endgame tactics Chess Puzzles

Background reading

Opposite-colored bishops endgame

The opposite-colored bishops endgame is a chess endgame in which each side has a single bishop and those bishops operate on opposite-colored squares. Without other pieces besides pawns and the kings, these endings are widely known for their tendency to result in a draw. These are the most difficult endings in which to convert a small material advantage to a win. With additional pieces, the stronger side has more chances to win, but still not as many as when bishops are on the same color. Many players in a poor position have escaped a loss by trading down to such an endgame. These endgames are normally drawn when one side has a one-pawn advantage. Two or even three extra pawns may not suffice for a win either, since the weaker side can create a blockade on the squares on which their bishop operates.

General principles

Edmar Mednis gives two principles for endgames with bishops on opposite colors: # If a player is down material he should look for drawing chances in an endgame with only the bishops and pawns. # With major pieces (queen or rook) on the board, having bishops on opposite colors favors the side with an attack. Ian Rogers gives three principles when there are only the bishops and pawns: # Two connected pawns are not sufficient to win unless they reach their sixth rank. # If the attacker has two widely separated passed pawns that cannot be controlled by the opposing bishop on a single diagonal, they usually win. # When the attacker has an outside passed pawn, it should be stopped by the bishop only when the king can block the opposing king.

Drawing tendency

In endings with opposite-colored bishops, a material advantage is much less important than in most endgames and position is more important. Positions where one side has an extra pawn are usually drawn, and it is not uncommon to have two extra pawns (occasionally more) and to be unable to make progress. About half of the endings with a bishop and two pawns versus a bishop on the opposite color are drawn. (By contrast, over 90% are won if the bishops are on the same color.) Zugzwang is a tool that often helps the superior side win an endgame. It is a fairly common occurrence in endings with bishops on the same color but is much less common in endgames with opposite-colored bishops. The weaker side should often try to make his bishop bad by placing his pawns on the same color of his bishop in order to defend his remaining pawns, thereby creating an impregnable fortress. The attacker should generally put his pawns on squares of the opposite color as his bishop to prevent a blockade.

Bishop and pawn versus bishop

This is almost always a draw. The attacker's bishop is practically useless and the defender should draw if his king can reach any square in front of the pawn that is not of the color of the attacking bishop; or if his bishop can permanently attack any square in front of the pawn. These endings are trivially drawn 99% of the time.

Bishop and two pawns versus a bishop

About half of these positions are drawn. In most other endings, a two-pawn advantage is usually an easy win. For comparison, if the bishops were on the same color squares, over 90% of the positions would be wins. There are three general cases, depending on the two pawns. In most endings, a pair of connected pawns have the best winning chances, but in these endings, a widely separated pair of pawns have the best chances unless one of the pawns is the wrong rook pawn.

Doubled pawns

With doubled pawns, the position is a draw if the defending king can reach any square in front of the pawns that is not of the color of the attacker's bishop. The second pawn on the file is of no help, so this is like the ending with only one pawn. If the defending king and bishop cannot accomplish this, the first pawn will win the defending bishop and the second one will promote.