The drawing tendency

A pawn up — and still a draw.

When each side has a bishop and they travel on opposite colours, the bishops can never challenge each other or trade. That makes these endings extraordinarily drawish: the defender sets up a blockade on the colour of his OWN bishop — squares the attacker's bishop can never attack — and the extra pawns simply can't break through.

The rule of thumb: with opposite-coloured bishops, the defender often holds a draw a pawn (sometimes two) down. The attacker only wins with a big material edge AND passed pawns far enough apart to stretch the defence past breaking point. When you're worse, steer INTO opposite bishops; when you're better, think twice before trading into them.

Opposite bishops can't trade — the defender blockades on his own colour.
A pawn (often two) down is frequently still a draw.
Worse? Trade into opposite bishops. Better? Avoid them.

White is a clean pawn up — but it's a draw. Black blockades the e5-square with his king; White's light-squared bishop can never control e5 or evict the king, and the pawn can't advance alone.

Why are opposite-coloured-bishop endings so often drawn, even a pawn down?

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