<p>A completely identical board position <strong>MUST NOT</strong> appear twice in one game. Therefore, before you can recapture a stone that just captured yours, you have to <strong>PLAY ELSEWHERE</strong> at least <strong>ONCE</strong>. This called "Ko".</p><p>Go games can be really long. However, they must never be endless. The “Ko” rule is created to prevent that.&nbsp;</p>

No Repetition (“Ko”)

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            <a href="https://www.learn-go.net/index.html#rules" dir="ltr"><div dir="ltr"><span dir="ltr">BACK</span> to menu</div></a>


</div><h1>| No Repetition (A rule called “Ko”)</h1><h2>No repetition ever</h2><BLOCKQUOTE><p>Full disclosure - this is a rule that may confuse you at first. Fortunately, it is not as complicated as it may first appear. I for one (although many would disagree) think that a good ko fight is one of the most fun things you can have in a Go game.</p></BLOCKQUOTE><p><strong>Go games can be really long. However, they must never be endless. To prevent the possibility of an endless game we have a rule called “Ko”.</strong></p><p>Just imagine a situation like this one. Given enough stubbornness, those players would be playing until they pass out. (feel free to watch for a while)</p><img src="https://www.learn-go.net/images/ko.gif" alt="ko diagram" width="486" height="487"><p>To prevent health problems connected with exhaustion, we have this rule:</p><div dir="ltr">
    A completely identical board position <span dir="ltr">must not</span> appear twice in one game.
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Therefore, before you can recapture a stone that just captured yours, you have to <span dir="ltr">play elsewhere</span> at least <span dir="ltr">once</span>.
</div><p><strong>Can you ever capture that stone then? What are your options? Basically, you have two:</strong></p><p>⬤  You deem the stone not important for now and play elsewhere, letting your opponent end the ko by connecting her endangered stone if he or she wants to.</p><p>⬤  You deem the stone important enough to fight the ko. You still have to play elsewhere (of course) but you try to find a move your opponent will feel compelled to respond to immediately instead of resolving the original ko (we call that a ko-threat). After that, you retake the ko stone and the fight is on!</p><p><em>Confusing? Then check out the following examples. It will be clear in no time.</em></p><div dir="ltr">
        
            <button onclick="loadTsumego(&quot;4-1&quot;, &quot;pzl1&quot;, tsumego)" dir="ltr">Puzzle 1</button>
        
            <button onclick="loadTsumego(&quot;4-2&quot;, &quot;pzl2&quot;, tsumego)" dir="ltr">Puzzle 2</button>
        
            <button onclick="loadTsumego(&quot;4-3&quot;, &quot;pzl3&quot;, tsumego)" dir="ltr">Puzzle 3</button>
        
    <br dir="ltr"><br dir="ltr">
    </div><p>Black to play</p><div><button disabled="">Retry</button></div><div><button disabled="">Undo</button></div><div><button>Hint</button></div><p>And on 19x19 board, there are usually much more than only one threat, so the ko fight can span over several moves.
The hard part - of course - is judging if any given threat is big enough to respond to or whether it is more beneficial to end the ko. But hey, I said the rules are easy, not the game itself.</p><div onclick="setProgress('4', '1', '99'); myFunction('/lessons\/05')" dir="ltr"><span dir="ltr">I understand, </span><br dir="ltr">what's next?</div>

strategy

Strategy

<p>Full disclosure - this is a rule that may confuse you at first. Fortunately, it is not as complicated as it may first appear. I for one (although many would disagree) think that a good ko fight is one of the most fun things you can have in a Go game. </p>

<p><strong>Go games can be really long. However, they must never be endless. To prevent the possibility of an endless game we have a rule called “Ko”. </strong> </p>

<p>Just imagine a situation like this one. Given enough stubbornness, those players would be playing until they pass out. (feel free to watch for a while) </p>

<p>To prevent health problems connected with exhaustion, we have this rule: </p>

<p><strong>Can you ever capture that stone then? What are your options? Basically, you have two: </strong> </p>

<p>⬤ You deem the stone not important for now and play elsewhere, letting your opponent end the ko by connecting her endangered stone if he or she wants to. </p>

<p>⬤ You deem the stone important enough to fight the ko. You still have to play elsewhere (of course) but you try to find a move your opponent will feel compelled to respond to immediately instead of resolving the original ko (we call that a ko-threat). After that, you retake the ko stone and the fight is on! </p>

<p><em>Confusing? Then check out the following examples. It will be clear in no time. </em> </p>

<p>And on 19x19 board, there are usually much more than only one threat, so the ko fight can span over several moves. The hard part - of course - is judging if any given threat is big enough to respond to or whether it is more beneficial to end the ko. But hey, I said the rules are easy, not the game itself. </p>

Ko | Learn to Play Go

No Repetition (“Ko”)

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