Most important rules and principles in endings of opposite-coloured bishops
1) Most of the time, material is not as important as positional considiration
2) The defender's aim is to construct an impregnable fortress of one of the following typed:
Type 1: The king stops the passed pawn, while the bishop protects the other pawns.
Type 2: The bishop stops the passed pawns while the king assists it and stops the atacking king breaking through.
3) If a fortress of the second type can be broken, then the attacker usually creates two passed pawns on different wings and his king helps one pawn to advance, eventually winning the bishop.
4) If the attacker sacrifices material himself to create passed pawns, his bishop must be able to halt the resulting enemy passed pawns on diagonal. The principle of one diagonal is important for the attacker and the defender as a methode to avoid falling into zugzwang or being diverted.
5) As defender, attack your opponent's pawns with your bishop to force them onto squares of the opposite colour to your bishop. It is then easier to create a safe blockade.
Opposite coloured bishops