battery

The idea

Two of your long-range pieces line up one behind the other and strike the same point. Your opponent can capture the first, but the second immediately carries on.

The idea is that the pieces support each other. The front one can safely step into danger: its partner stands behind, so capturing it achieves nothing.

How it looks

A queen and a rook on the same file. Or a queen and a bishop on the same diagonal, aimed at a square next to the enemy king.

The strongest battery is rook, rook and queen on one line. Such a line is almost impossible to hold.

How to spot it

Before attacking the king, look for a way to line up two pieces one behind the other, aimed at a weak square.

The name comes from artillery, where the guns stand in a row. That is a useful reminder: the pieces must be on the same line, not hitting one square from different directions.

Often confused with

An X-ray attack. If two of your pieces hit the same point but from different directions, and an enemy piece blocks one of them, that is an X-ray, not a battery.