Answers.Body: <p>The two sources I'd depend upon to answer this question are <em>actual games</em> played by GM's (best), and <em>engine analysis</em>, carried to a depth of at least 24 ply (12 moves by each side).</p>
  
  <p>Here's what I get:</p>
  
  <h3>Actual Games</h3>
  
  <pre><code>Move     Games  Win %  Latest  Players
  4 d4      2947  57.3    2016   Carlsen, Kasparov, Karjakin, Anand
  4 Bb5      513  57.8    2016   Grischuk, Karjakin, Morozevich, Adams
  4 Bc4      229  47.2    2016   Vallejo Pons, Movsesian, Lu SHanglei, Zhigalko
  4 g3       153  48.4    2010   Mamedyarov, Romanishin, Galego, Biyiasas
  4 h4        38  43.4    2012   Hamdouchi, Pilavov, Minasian, Pridorozhni
  </code></pre>
  
  <p>So, the move is pretty unpopular at the highest levels (about 1% of games), and since Black outscores White by 57%-43% in this line, it's no wonder.</p>
  
  <hr>
  
  <h3>Engine Analysis</h3>
  
  <pre><code>Engine parameters: Stockfish 7, QuadCore AMD CPU using 4 Cores, Depth=25/39
  Line Move    Eval
   a.  4 Bb5   0.17
   b.  4 d4    0.13
   c.  4 h3    0.13
   d.  4 Rb1   0.11
   e.  4 a4    0.10
   f.  4 Bc4   0.09
   g.  4 a3    0.03
   h.  4 Be2   0.01
   i.  4 d3    0.00
  </code></pre>
  
  <hr>
  
  <p>That's <em>9 lines</em> that are better than 4 h4, and the 9th has an evaluation of dead equal, implying that the move 4 h4 must have a lower evaluation. Note that 4 h4 starts at among the top four moves until the engine reaches a depth of about 15-17 ply, and then falls off the map.  So the blowback seems to occur somewhere between move 11 and move 13.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-11-27T21:49:19.307Z
Answers.LastActivityDate: 2016-11-27T21:49:19.307Z
Answers.UserDisplayName: jaxter
Answers.Body: <p>4.h4 is a decent move, is not objectively best, but that doesnt matter unless you are playing a GM.</p>
  <p>I play the accelerated dragon myself and know early h4s  can be a pain to deal with. The usual approach when your opponent &quot;wastes&quot; moves on the flank early on is to go for opening of the center to exploit better development, however in the sicilian blacks development is usually slower anyway, since he already starts with a nondeveloping move c5, so is hard to flip the script like that.</p>
  <p>For instance in one tournament game of mine the game went</p>
  <pre><code>1.e4 c5 2.Nc3 g6 3.h4 {i decided to follow the formula and go for opening the center and played} 3...Nc6 4.h5 Nf6 5.hxg6 fxg6 6.Nf3 d5 7.exd5 Nxd5 8.Bc4 {here i discovered to my surprise that i wasn't ahead in development at all, and with my kingside ruined i went on to lose without ever finding the time to castle queenside (which might not have been that safe either)}
  
   [FEN &quot;&quot;]
  </code></pre>
  <p>In your given position i guess the idea is to sac the h pawn.</p>
  <pre><code>1.e4 c5 2. Nf3 Nc6 3. Nc3 g6 4.h4 Nf6 5.h5 Nxh5 6.d4 cxd4 7.Nxd4 {when the open h file and better development means black's king will have no safe place to castle, which i would say gives good enough compensation below GM level.}
  
  [FEN &quot;&quot;]
  </code></pre>
  
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Answers.LastEditDate: 2020-06-17T09:59:59.497Z
Answers.UserDisplayName: wannabecapablanca
Answers.Body: <p>The move 4 h4 can have some surprise effect, but it certainly goes against the general opening principle of piece development as primary goal <strong>and</strong> the other principle that flank attacks can be undertaken only if the situation in the centre is clarified.</p>
  
  <p>Given that, it may well be not a real bad move in the sense that it doesn't lead to a clear advantage for black.</p>
  
  <p>Do you know of occurrences of 4 h4 at the (grand)master level?</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-11-27T18:08:56.580Z
Answers.Text: To be honest I have not checked if (grand)masters use this move. I just saw a guide in youtube concerning this move and I wanted to get opinions from people about it
Answers.UserDisplayName: Giannis
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Answers.Text: FYI - I identified GM's in my response, above (posted after yours): 
  Hamdouchi, Pilavov, Minasian, Pridorozhni
Answers.UserDisplayName: jaxter
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Answers.UserDisplayName: Andrea Mori
Body: <p>What are the best moves for white after the following moves</p>
  
  <pre><code>[FEN ""]
  
  1. e4 c5 2. Nf3 Nc6 3. Nc3 g6
  </code></pre>
  
  <p>One aggressive choice here is <strong>4. h4</strong>.</p>
  
  <p>which can potentially damage the pawn structure or harass the bishop if he is deployed to g7. Is this a fairly good move? What are other alternatives in this position?</p>
  
Tags: <opening><sicilian-defense>
Title: Attacking the accelerated dragon
ThreadText: # Attacking the accelerated dragon
  
  (Asked by: username_0 on 2016-11-24)
  
  What are the best moves for white after the following moves
  
  ```
  [FEN ""]
  
  1. e4 c5 2. Nf3 Nc6 3. Nc3 g6
  
  ```
  
  One aggressive choice here is **4. h4**.
  
  which can potentially damage the pawn structure or harass the bishop if he is deployed to g7. Is this a fairly good move? What are other alternatives in this position?
  
  **Tags:** opening, sicilian-defense
  
  
  ---
  
  ## 3 answers
  
  ### Answer by username_1 on 2016-11-27. Score: 3 | Accepted answer
  
  The two sources I'd depend upon to answer this question are *actual games* played by GM's (best), and *engine analysis*, carried to a depth of at least 24 ply (12 moves by each side).
  
  Here's what I get:
  
  ### Actual Games
  
  ```
  Move     Games  Win %  Latest  Players
  4 d4      2947  57.3    2016   Carlsen, Kasparov, Karjakin, Anand
  4 Bb5      513  57.8    2016   Grischuk, Karjakin, Morozevich, Adams
  4 Bc4      229  47.2    2016   Vallejo Pons, Movsesian, Lu SHanglei, Zhigalko
  4 g3       153  48.4    2010   Mamedyarov, Romanishin, Galego, Biyiasas
  4 h4        38  43.4    2012   Hamdouchi, Pilavov, Minasian, Pridorozhni
  
  ```
  
  So, the move is pretty unpopular at the highest levels (about 1% of games), and since Black outscores White by 57%-43% in this line, it's no wonder.
  
  ---
  
  ### Engine Analysis
  
  ```
  Engine parameters: Stockfish 7, QuadCore AMD CPU using 4 Cores, Depth=25/39
  Line Move    Eval
   a.  4 Bb5   0.17
   b.  4 d4    0.13
   c.  4 h3    0.13
   d.  4 Rb1   0.11
   e.  4 a4    0.10
   f.  4 Bc4   0.09
   g.  4 a3    0.03
   h.  4 Be2   0.01
   i.  4 d3    0.00
  
  ```
  
  ---
  
  That's *9 lines* that are better than 4 h4, and the 9th has an evaluation of dead equal, implying that the move 4 h4 must have a lower evaluation. Note that 4 h4 starts at among the top four moves until the engine reaches a depth of about 15-17 ply, and then falls off the map. So the blowback seems to occur somewhere between move 11 and move 13.
  
  
  ---
  
  ### Answer by username_2 on 2016-11-27. Score: 2
  
  4.h4 is a decent move, is not objectively best, but that doesnt matter unless you are playing a GM.
  
  I play the accelerated dragon myself and know early h4s can be a pain to deal with. The usual approach when your opponent "wastes" moves on the flank early on is to go for opening of the center to exploit better development, however in the sicilian blacks development is usually slower anyway, since he already starts with a nondeveloping move c5, so is hard to flip the script like that.
  
  For instance in one tournament game of mine the game went
  
  ```
  1.e4 c5 2.Nc3 g6 3.h4 {i decided to follow the formula and go for opening the center and played} 3...Nc6 4.h5 Nf6 5.hxg6 fxg6 6.Nf3 d5 7.exd5 Nxd5 8.Bc4 {here i discovered to my surprise that i wasn't ahead in development at all, and with my kingside ruined i went on to lose without ever finding the time to castle queenside (which might not have been that safe either)}
  
   [FEN ""]
  
  ```
  
  In your given position i guess the idea is to sac the h pawn.
  
  ```
  1.e4 c5 2. Nf3 Nc6 3. Nc3 g6 4.h4 Nf6 5.h5 Nxh5 6.d4 cxd4 7.Nxd4 {when the open h file and better development means black's king will have no safe place to castle, which i would say gives good enough compensation below GM level.}
  
  [FEN ""]
  
  ```
  
  
  ---
  
  ### Answer by username_3 on 2016-11-27. Score: 1
  
  The move 4 h4 can have some surprise effect, but it certainly goes against the general opening principle of piece development as primary goal **and** the other principle that flank attacks can be undertaken only if the situation in the centre is clarified.
  
  Given that, it may well be not a real bad move in the sense that it doesn't lead to a clear advantage for black.
  
  Do you know of occurrences of 4 h4 at the (grand)master level?
  
  > **Comments:**
  > **username_0**: To be honest I have not checked if (grand)masters use this move. I just saw a guide in youtube concerning this move and I wanted to get opinions from people about it  
  > **username_1**: FYI - I identified GM's in my response, above (posted after yours):  Hamdouchi, Pilavov, Minasian, Pridorozhni  
  
  ---
  
  