user8456: Look at this puzzle:
[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]

The aim of the puzzle is: Black to play and attain a good position. But I can't find a good position here. Then I looked at the solution, which was 1... Nc4!! . But I can't understand what happens after this move. I think both sides are equal. Can anyone help me?

user7644: Wait it is not over yet :)
The queen trap from ..Nc4 can be avoided. White can give a check 1. ..Nc4 2. Nh4 ..Bxh4 3. Bxc7. 
You can also prevent the knight trapping the queen by giving that check beforehand. Thats another way around.
Apologies i am just a beginner, not good with chess notations, but he point is queen can be saved using Whites black bishop. I may be wrong.

user7297: Black will trap the queen on the next move, either with Bd6 or b6. For example:
[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]

1... Nc4 2. b3 Bd6 3. bxc4 Bxc5 4. dxc5 dxc4

and with a queen and a (passed) pawn for two minor pieces, Black will have no problems to win this game.

8456: <p>Look at this puzzle:</p>

<pre><code>[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]
</code></pre>

<p>The aim of the puzzle is: Black to play and attain a good position. But I can't find a good position here. Then I looked at the solution, which was 1... Nc4!! . But I can't understand what happens after this move. I think both sides are equal. Can anyone help me?</p>
 7644: <p>Wait it is not over yet :)</p>

<p>The queen trap from ..Nc4 can be avoided. White can give a check <code>1. ..Nc4 2. Nh4 ..Bxh4 3. Bxc7.</code> </p>

<p>You can also prevent the knight trapping the queen by giving that check beforehand. Thats another way around.</p>

<p>Apologies i am just a beginner, not good with chess notations, but he point is queen can be saved using Whites black bishop. I may be wrong.</p>
 7297: <p>Black will trap the queen on the next move, either with Bd6 or b6. For example:</p>

<pre><code>[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]

1... Nc4 2. b3 Bd6 3. bxc4 Bxc5 4. dxc5 dxc4
</code></pre>

<p>and with a queen and a (passed) pawn for two minor pieces, Black will have no problems to win this game.</p>
