user4399: Position that follows is from Anna Rudolf's video 'Challenging Top Chess Grandmaster Hikaru Nakamura for a Choker Match!':
[FEN "8/5p2/8/2qkp3/4R1P1/5P2/3KP3/8 b - - 0 1"]

Also, here's a screenshot:

In the game, Anna was running low on time and forced a draw by repetition (there was no draw offer button at the time and maybe even now).

How does Anna beat Hikaru? I tried checking out lichess and it seems an idea is to trade rook and pawn for queen but even though it's 2 pawn vs 2 pawns, the pawn endgame is winning for black (Anna). Below is what I got from the 1st time I pressed spacebar until the pawn endgame. (At higher depth, I didn't get this again.)


[FEN "8/5p2/8/2qkp3/4R1P1/5P2/3KP3/8 b - - 0 1"]

1... Qa7 2. Ke1 Qg1+ 3. Kd2 Qb1 4. Ke3 Qc2 5. Kf2 Qxe4 6. fxe4+ Kxe4



Hikaru says something about 'zugzwang with Qd1'. What is Hikaru talking about? I know it's possibly related to fortresses (hence i tagged fortress) because in the video they were talking about 'I don't believe in fortresses' lol


user11144: Eric Half-An-Answer: He talks about a fortress, obviously :-) As far as one can talk generally, when trying to storm a fortress in a position with material Q/R plus pawns, the win method often is to use zugzwang to pass with the king through the blockade line built by the rook (here: at the moment the black king can't make it over the 4th) and then attack the pawn basis with the king from below.
BTW, another common strategy (but I bet it is not applicable here, since White is a pawn up) we just recently saw in a top game is the queen shielding the king with her own life (as taking her would create a passer), for example Kh2 Rh3 Pg2 - Ke4 Qd4 Pf4, where Qe3! wins fastest. Again the idea is attacking the base from below with the king.
This is only Eric Half-An-Answer as I am too weak a player to "see" the concrete zugzwang position with Qd1. I can make an educated guess: Assuming that the wR is fixed to e4 as Re3 allows the bK to near further, and R?4 runs into a fork (which I don't see yet), Kf2 vs Qd1 is already zugzwang: Ke3 Qe1 and the rook must move, Kg2 Qe1 ditto. Let Stockfish sort that out.

4399: <p><a href="https://lichess.org/analysis/8/5p2/8/2qkp3/4R1P1/5P2/3KP3/8_b_-_-_0_1#1" rel="nofollow noreferrer">Position</a> that follows is from Anna Rudolf's <a href="https://youtu.be/1E4WvgTYut4?t=477" rel="nofollow noreferrer">video 'Challenging Top Chess Grandmaster Hikaru Nakamura for a Choker Match!'</a>:</p>
<pre><code>[FEN &quot;8/5p2/8/2qkp3/4R1P1/5P2/3KP3/8 b - - 0 1&quot;]
</code></pre>
<p>Also, here's a screenshot:</p>
<p><a href="https://i.stack.imgur.com/6XEzx.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6XEzx.jpg" alt="enter image description here" /></a></p>
<p>In the game, Anna was running low on time and forced a draw by repetition (there was no draw offer button at the time and maybe even now).</p>
<ol>
<li>How does Anna beat Hikaru? I tried checking out lichess and it seems an idea is to trade rook and pawn for queen but even though it's 2 pawn vs 2 pawns, the pawn endgame is winning for black (Anna). Below is what I got from the 1st time I pressed spacebar until the pawn endgame. (At higher depth, I didn't get this again.)</li>
</ol>
<hr />
<pre><code>[FEN &quot;8/5p2/8/2qkp3/4R1P1/5P2/3KP3/8 b - - 0 1&quot;]

1... Qa7 2. Ke1 Qg1+ 3. Kd2 Qb1 4. Ke3 Qc2 5. Kf2 Qxe4 6. fxe4+ Kxe4
</code></pre>
<hr />
<ol start="2">
<li>Hikaru says something about 'zugzwang with Qd1'. What is Hikaru talking about? I know it's possibly related to fortresses (hence i tagged fortress) because in the video they were talking about '<a href="https://twitter.com/gmhikaru/status/1063544866213429248" rel="nofollow noreferrer">I don't believe in fortresses</a>' lol</li>
</ol>
 11144: <p>Eric Half-An-Answer: He talks about a fortress, obviously :-) As far as one can talk generally, when trying to storm a fortress in a position with material Q/R plus pawns, the win method often is to use zugzwang to pass with the king through the blockade line built by the rook (here: at the moment the black king can't make it over the 4th) and then attack the pawn basis with the king from below.</p>
<p>BTW, another common strategy (but I bet it is not applicable here, since White is a pawn up) we just recently saw in a top game is the queen shielding the king with her own life (as taking her would create a passer), for example Kh2 Rh3 Pg2 - Ke4 Qd4 Pf4, where Qe3! wins fastest. Again the idea is attacking the base from below with the king.</p>
<p>This is only Eric Half-An-Answer as I am too weak a player to &quot;see&quot; the concrete zugzwang position with Qd1. I can make an educated guess: Assuming that the wR is fixed to e4 as Re3 allows the bK to near further, and R?4 runs into a fork (which I don't see yet), Kf2 vs Qd1 is already zugzwang: Ke3 Qe1 and the rook must move, Kg2 Qe1 ditto. Let Stockfish sort that out.</p>
