ko threat

A ko threat is a move played elsewhere on the board that threatens a sufficiently valuable result to require an answer. After making a ko capture, a player uses such a move to gain a response in another location and regain the initiative before continuing the ko fight.

If the opponent answers the threat, the player may recapture the ko. If the opponent ignores it, the threatened result occurs. This can also be worthwhile when the player obtains a favorable result even without continuing the ko. A ko threat is specifically tied to the timing of a ko fight: although it is often sente, not every sente move is a ko threat. Its effectiveness depends on the value and urgency of the threat; a move small enough to ignore is not a useful ko exchange.