Opposite-colored bishops
Opposite-colored bishops are bishops that run on different shades of squares, so neither side can attack or exchange the other's bishop, which makes endings with them notoriously drawish even when one side is a pawn or two ahead.
Also called: opposite-color bishops
When each side has one bishop and they travel on different colors, the bishops can never meet. That single fact reshapes the ending. The defender sets up a blockade with the king and bishop on squares of the bishop's own color, which the attacking bishop can never challenge, and this often holds a draw even a pawn or two down. To win, the attacker usually needs passed pawns far enough apart that the king and bishop cannot stop both. This is why strong players with an extra pawn often avoid trading into this structure. In the middlegame the same bishops tend to help the attacker instead, because each bishop works alone on its own color and the defender has no bishop to cover the squares the attacker's bishop controls. A common mistake is to assume the extra pawn is enough and trade everything else off, which only brings the draw closer. Another is to ignore the fortress: put your pawns on the color of your own bishop so it protects them, and keep the king in front of the enemy pawns.
Compare it with Minor piece endgame. A minor piece endgame is an ending in which each side has only bishops or knights besides the kings and pawns, so the fight turns on piece activity, pawn structure and king position rather than on heavy pieces.
A neighboring idea is Same-colored bishops. Same-colored bishops are bishops that move on the same shade of squares, so they can challenge, exchange and defend against each other, and an extra pawn is usually much easier to convert than with opposite colors.
Also worth reading is Two bishops checkmate. Two bishops checkmate is the ending in which a king and two bishops, one on light squares and one on dark squares, force mate against a lone king, usually in a corner, with the king helping.
Endgame ideas like "Opposite-colored bishops" are won or lost on small details, which a coach can check in your own games. The first lesson with George Li is where that review starts.
Related terms
Same-colored bishops are bishops that move on the same shade of squares, so they can challenge, exchange and defend against each other, and an extra pawn is usually much easier to convert than with opposite colors.
A minor piece endgame is an ending in which each side has only bishops or knights besides the kings and pawns, so the fight turns on piece activity, pawn structure and king position rather than on heavy pieces.
A fortress is a position the weaker side can hold indefinitely: its king, pieces and pawns cover every entry route, so the side with extra material has nothing to aim at and the game ends in a draw.
A theoretical draw is a position in which perfect play by both sides leads to a draw, so neither player can force a win no matter how many moves are left.
A color complex is a group of squares of one color around a king or pawn structure that turns weak when the defender has traded the bishop that guards them and left pawns on the opposite color.
A good bishop is one whose own pawns mainly stand on the other color from the squares it travels on, so its diagonals stay open and it can reach the enemy camp.
Guides that go further
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