user8672: [fen "6r1/1p3k2/2rb1p1p/3NpP1P/PpPp2pR/1P1K2P1/4RP2/8 b - - 0 1"]

If Black holds his bishop on c5, rook on a8/a5 (if a5 is a threat), rook on g8 (protect g4) or the 8th rank, is there any way for White to break through?
If so, what would be the best defense for Black?
Black to move. He will play Rg5.

user9400: I believe if white breaks through, then black has some counter play chances on the queen side. For instance: 
[FEN "6r1/1p3k2/2rb1p1p/3NpP1P/PpPp2pR/1P1K2P1/4RP2/8 b - - 0 1"]

1... Rg5 2. Re4 Rxf5 3. Rhxg4 Rf3+ 4. Ke2 Rxb3 5. Rg6 Bf8 6. f4 Bg7 7. fxe5 fxe5 8. Reg4 Bf8

and white's queen side pawns are gone and black has serious threats.
Otherwise if white try to holds on his pawns, there is no way to make any progress and the game will be draw.

8672: <pre><code>[fen "6r1/1p3k2/2rb1p1p/3NpP1P/PpPp2pR/1P1K2P1/4RP2/8 b - - 0 1"]
</code></pre>

<p>If Black holds his bishop on c5, rook on a8/a5 (if a5 is a threat), rook on g8 (protect g4) or the 8th rank, is there any way for White to break through?</p>

<p>If so, what would be the best defense for Black?</p>

<p>Black to move. He will play Rg5.</p>
 9400: <p>I believe if white breaks through, then black has some counter play chances on the queen side. For instance: </p>

<pre><code>[FEN "6r1/1p3k2/2rb1p1p/3NpP1P/PpPp2pR/1P1K2P1/4RP2/8 b - - 0 1"]

1... Rg5 2. Re4 Rxf5 3. Rhxg4 Rf3+ 4. Ke2 Rxb3 5. Rg6 Bf8 6. f4 Bg7 7. fxe5 fxe5 8. Reg4 Bf8
</code></pre>

<p>and white's queen side pawns are gone and black has serious threats.</p>

<p>Otherwise if white try to holds on his pawns, there is no way to make any progress and the game will be draw.</p>
