Ladder in Go — How Shicho Capture Sequences Work | PlayGo.gg

A position in which one side can keep putting the other in atari until an eventual capture.

What is a ladder?

A ladder begins when one player puts an opponent's stone in atari (one liberty remaining). The chased stone extends to escape, but extending only gives it two liberties — and the chaser immediately re-ataris from the diagonal direction. The pattern repeats: atari, extend, atari, extend, marching diagonally across the board until the chased stones reach the edge and run out of room.

Because each response is forced, both players know how it ends before it begins. That's exactly why reading ladders is one of the first reading skills every Go player has to learn.

When to use a ladder?

Use a ladder whenever an opponent's cutting or invading stone has only two liberties and no friendly help on the diagonal it would travel. Before starting the chase, count the squares to the edge and scan that diagonal — even a single friendly stone of the chased color along the path becomes a ladder breaker that turns the whole sequence into a disaster.

A ladder breaker placed many points away can completely change the result. This is one of Go's most striking strategic features: a stone in the upper-right corner can decide a fight in the lower-left fifteen moves later.

Example of a ladder in a game

Can you make a ladder here as black?

Ladders are the clearest example of how reading ahead pays off in Go. Count the diagonal, find the breaker, and decide before you commit. Strong players never start a ladder they haven't already finished in their head.