Semeai

A semeai is a situation where two groups of stones are locked in a race to capture each other. Neither group can make two eyes independently, so the outcome depends entirely on which group can capture the other first. 

The term semeai comes from Japanese and means “mutual attack” or “contest of attack,” aptly describing the intense and tactical nature of this fight. In English, it is often referred to as a “capturing race.” 

The critical factor in a semeai is the number of liberties (empty spaces next to the stones) that each group has. Accurate counting and careful management of these liberties are essential, as even a single misstep can tip the balance of the capturing race.

An example of simple capturing race from a real game

In addition to counting liberties, having the initiative, or sente, plays a vital role. The ability to force the opponent into defensive moves can create opportunities to gain an advantage in the race. Engaging in a capturing race also demands deep reading and foresight, as players must anticipate sequences of moves and carefully evaluate their repercussions.

If you want to deepen your understanding of capturing races in Go and learn how to navigate these intense battles effectively, check out It’s a Capturing Race! lesson in our Deeper into the Game of Go on 19×19 course. This lesson breaks down the key concepts and strategies needed to master this critical aspect of the game.