user21403: This puzzle on chesstempo caught my eye. We play as Black:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1"]

1.Rgxg5


Note: the solution is not quite important here, so no large spoilers from me :).

The main blunder here is playing 1... Bxf5. One of the comments runs:

...Black is a step away from certain death after 1...Bxf5 2.Qxf5...

They show this board:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1"]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Qd2 4.f7 Qf4 5.Qe6 h5 6.Rg8+ Rxg8 7.fxg8=Q+ Rxg8 8.Qxg8#

Is mate threat really a thing here? I believe the mate threat actually begins at 3... Qd2 4. f7. Here's how I would've answered:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1"]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5

I reckon 3... Rxd5 to force White into some exchange, as merely playing 4. xd5 would end up in a mate threat from Black:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1"]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5 4. cxd5 Qxd5+ 5. Rg2 Rg8

The exchange would be:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1"]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5 4. Rxd1 Rxd1+

So, who is wrong here? Am I failing to choose the best moves for White, or is the board in the comments actually faulty?

user-1: I Suspect that after 3... Rxd5 4. f7 is strong enough:
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1"]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7

The obvious threat is Qf6 mate. Starting with the variations in which black tries to cover f6 we have:

If 4...Rb6 then 5. f8=R#
If 4...Rd6 then 5. Qxe5 Rf6 6. Qxf6#

Since all variations leads to checkmate there is no way to cover f6 and black must resort to giving up the queen.
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1"]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7 Qxg1 5. Kxg1

Yet again Qf6 is mate and obviously black cannot move the rook from the 8:th rank because f8 mate. If 5... Rd6 then 6. Qxe5 Rf6 7. Qxf6#. This leaves us with the one last try of Rd1+ (if Kg7 immediately then cxd5):
[FEN "1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1"]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7 Qxg1 5. Kxg1 Rd1+ 6. Kg2 Kg7 7. Qxe5+ Kxf7 8. Qxb8

It is not a mate but undoubtedly white is winning

21403: <p><a href="https://chesstempo.com/chess-problems/90726" rel="noreferrer">This puzzle</a> on <a href="https://chesstempo.com/" rel="noreferrer">chesstempo</a> caught my eye. We play as Black:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1&quot;]

1.Rgxg5
</code></pre>
<hr />
<p><strong>Note:</strong> <em>the solution is not quite important here, so no large spoilers from me :).</em></p>
<hr />
<p>The main blunder here is playing 1... Bxf5. One of the comments runs:</p>
<blockquote>
<p>...Black is a step away from certain death after 1...Bxf5 2.Qxf5...</p>
</blockquote>
<p>They show this board:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1&quot;]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Qd2 4.f7 Qf4 5.Qe6 h5 6.Rg8+ Rxg8 7.fxg8=Q+ Rxg8 8.Qxg8#
</code></pre>
<p>Is mate threat really a thing here? I believe the mate threat actually begins at 3... Qd2 4. f7. Here's how I would've answered:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1&quot;]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5
</code></pre>
<p>I reckon 3... Rxd5 to force White into some exchange, as merely playing 4. xd5 would end up in a mate threat from Black:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1&quot;]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5 4. cxd5 Qxd5+ 5. Rg2 Rg8
</code></pre>
<p>The exchange would be:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 1 1&quot;]

1.Rgxg5 Bxf5 2.Qxf5 Qd1+ 3.Rg1 Rxd5 4. Rxd1 Rxd1+
</code></pre>
<p>So, who is wrong here? Am I failing to choose the best moves for White, or is the board in the comments actually faulty?</p>
 -1: <p>I Suspect that after 3... Rxd5 4. f7 is strong enough:</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1&quot;]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7
</code></pre>
<p>The obvious threat is Qf6 mate. Starting with the variations in which black tries to cover f6 we have:</p>
<ul>
<li>If 4...Rb6 then 5. f8=R#</li>
<li>If 4...Rd6 then 5. Qxe5 Rf6 6. Qxf6#</li>
</ul>
<p>Since all variations leads to checkmate there is no way to cover f6 and black must resort to giving up the queen.</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1&quot;]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7 Qxg1 5. Kxg1
</code></pre>
<p>Yet again Qf6 is mate and obviously black cannot move the rook from the 8:th rank because f8 mate. If 5... Rd6 then 6. Qxe5 Rf6 7. Qxf6#. This leaves us with the one last try of Rd1+ (if Kg7 immediately then cxd5):</p>
<pre><code>[FEN &quot;1r1r3k/7p/5Pb1/p2BpRpq/1pP5/1P1Q4/P5RP/7K w - - 0 1&quot;]

1.Rgxg5 Bxf5 2. Qxf5 Qd1+ 3. Rg1 Rxd5 4. f7 Qxg1 5. Kxg1 Rd1+ 6. Kg2 Kg7 7. Qxe5+ Kxf7 8. Qxb8
</code></pre>
<p>It is not a mate but undoubtedly white is winning</p>
