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BasicKoThreats

 

Ko Threat
    Keywords: EndGame

A ko threat is a move which threatens something. They are used in a ko fight: When there is a ko which you are not allowed to immediately retake, you play a ko threat. This forces your opponent to answer, after which you can retake the ko, and now it is your opponent's turn to find a ko threat.

See for a clearer and more extensive explanation BasicKoThreats.


-Kris Rhodes (interrupting, sorry...): I want to insert a comment here for any relative beginners to the game before you get to the slightly complicated comments which follow in this page.

I think the simplest way to explain a ko threat is to say it is a place on the board where, if you could get two moves in a row, you would win a lot of points. So, if a ko situation happens, and you want to win that ko, then you can play the first of the abovementioned two moves (which need have no direct relationship to the actual area of the ko fight situation itself). Hopefully, this will demand a response by your opponent in that area of the board, and the ko will remain available for you to retake.

(If I have broken some rule of WikiEtiquette by inserting this comment, please tell me so. My email address is roodzu@yahoo.com)


What is a ko threat? Depending on your definition, every tenuki or pass could be called a ko threat. More generally, one speaks of restriction threats. If passes are involved or threatened to be involved, then one calls the particular restriction fights pass fights. --RobertJasiek


BillSpight: What is the threat of a ko threat?

Not the threat to retake the ko. Any board move does that (and sometimes passes, depending on the rules). The threat is to make another local play if the opponent wins the ko (or, in complicated kos, makes another play in the ko).

Yes, some people define ko threats so that every play or virtually every play is a ko threat. But that definition is so broad as to rob the term of its meaning, isn't it?

So we see that "ko" and "ko threat" definitions depend on the purposes of stating them. From a view of move legality about each move is a ko threat; from a view of perfect play fewer moves might be ko threats. --RobertJasiek

Sometimes ordinary plays (and even passes) have one of the functions of a ko threat. I used to call these phantom ko threats, but now I call them virtual ko threats?.

I classify ko threats according to function on ko threat functions.

Robert, how about a page on pass fights? I think people would find it interesting. :-)

No doubt, unfortunately, currently I lack time. Maybe somebody could cite my RGG contributions in the pass fight and virtual ko threat threads. Otherwise everybody must wait for GRE:) --RobertJasiek



This is a copy of the living page "Ko Threat" at Sensei's Library.
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