user7334: Any hints how to survive or win having a bishop pair against a Queen in endgames. What you should do? how to cooperate between them? what's the opponent best strategies?


user2042: This is one of the well known endgames and the side with the queen almost always (92% positions) wins, although some wins take more than 50 moves with perfect play.
See the solution for your position here by entering your position into the diagram.
I must point out that every move has been taken into account and every possible continuation has been explored.
I forgot to answer part of your question about challenging the queen: 

with best play side with the bishop loses most of the time, as stated above;
side with the bishops can never win, due to reasons user ETD pointed out in his comment;
in order to defend vs queen, use bishops to create barrier for the enemy king; keep them close to your king in order to be safe from double attacks queen can make.

It is worth noting, that the position shifted down by one row is a fortress setup and black draws. The setup is known as the Lolli position.
8/6k1/5bb1/8/2Q5/8/3K4/8 w - - 0 1


7334: <p>Any hints how to survive or win having a bishop pair against a Queen in endgames. What you should do? how to cooperate between them? what's the opponent best strategies?</p>

<p><img src="https://i.stack.imgur.com/uffkx.png" alt="bishop pair vs queen"></p>
 2042: <p>This is one of the well known endgames and the side with the queen almost always (<a href="https://en.wikipedia.org/wiki/Pawnless_chess_endgame#Tables" rel="nofollow">92% positions</a>) wins, although some wins take more than 50 moves with perfect play.</p>

<p>See the solution for your position <a href="http://www.k4it.de/?topic=egtb&amp;lang=en" rel="nofollow">here</a> by entering your position into the diagram.</p>

<p>I must point out that <strong>every</strong> move has been taken into account and <strong>every</strong> possible continuation has been explored.</p>

<p>I forgot to answer part of your question about challenging the queen: </p>

<ul>
<li>with best play side with the bishop loses most of the time, as stated above;</li>
<li>side with the bishops can <strong>never</strong> win, due to reasons user <em>ETD</em> pointed out in his comment;</li>
<li>in order to defend vs queen, use bishops to create barrier for the enemy king; keep them close to your king in order to be safe from double attacks queen can make.</li>
</ul>

<p>It is worth noting, that the position shifted down by one row is a fortress setup and black draws. The setup is known as the <a href="https://en.wikipedia.org/wiki/Fortress_%28chess%29#Two_bishops" rel="nofollow">Lolli position</a>.</p>

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