Answers.Body: <p>Sometimes, choosing a bishop or a rook is the best move, because of stalemate possibilities. This happens most often with rooks, and very rarely with bishops.</p>
  
  <p>For instance, in this famous position from the Saavedra problem:</p>
  
  <pre><code>[FEN "8/2P5/8/8/3r4/8/2K5/k7 w - - 0 1"]
  </code></pre>
  
  <p>If white plays <strong>1.c8Q</strong>, then black plays <strong>1...Rc4+</strong>. White needs to take it or lose his queen but after <strong>2.Qxc4</strong> it is stalemate.</p>
  
  <p>If instead white plays <strong>1.c8R</strong>, the stalemate trick doesn't work and 2.Ra8+ with checkmate next move is threatened. So black must play <strong>2...Ra4</strong>, but white plays <strong>3.Kb3</strong> attacking the rook and also threatening 4.Rc1 checkmate; black can't deal with both threats.</p>
  
  <p>On <a href="http://timkr.home.xs4all.nl/chess2/minor.htm" rel="noreferrer">Tim Krabbe's page on practical minor promotions</a> I found this example from Kholmov-Ehlvest 1983:</p>
  
  <pre><code>[FEN "2k5/2P5/1K2p3/7r/8/8/7p/R7 b - - 0 1"]
  [StartFlipped "0"]
  </code></pre>
  
  <p>(black to move)</p>
  
  <p>White threatens to play Ra8+ and c8Q+. If black promotes to a queen with <strong>1...h1Q</strong>, then that isn't enough for black to win: 2.Ra8+ Qxa8 is stalemate.
  Promoting to a rook or knight clearly doesn't help black.</p>
  
  <p>But after <strong>1...h1B</strong>, the check doesn't work, black is simply a piece up and has a winning position.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-08T15:25:32.557Z
Answers.Text: +1 because stalemate. Definitely the correct answer
Answers.UserDisplayName: Brandon_J
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2016-01-06T13:45:28.993Z
Answers.LastActivityDate: 2019-04-19T07:45:25.837Z
Answers.LastEditDate: 2019-04-19T07:45:25.837Z
Answers.UserDisplayName: RemcoGerlich
Answers.Body: <p>There are 3 types of piece moves in chess:</p>
  
  <ol>
  <li>Straight</li>
  <li>Diagonal</li>
  <li>Knight-move</li>
  </ol>
  
  <p>There are positions, where promoted piece takes away the last square that enemy king can move, and stalemates. This happens because of one of these move types.</p>
  
  <p>To avoid stalemate and win eventually, you have to select a promotion which doesn't have stalemating move, which is called underpromotion.</p>
  
  <p>For example, if diagonal move stalemates, you can't select queen as it has diagonal move ability. But you can select a rook, and go for a win.</p>
  
  <p>Example from famous Saavedra position:</p>
  
  <pre><code>[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 1 1"]
  [Title "Saavedra"]    
  
  1. c7 Rd6+ 2. Kb5 Rd5+ 3. Kb4 Rd4+ 4. Kb3 Rd3+ 5. Kc2 Rd4 6. c8=Q ( 6. c8=R Rc4+
  
  7. Rxc4 Ka2 8. Ra4# ) (6.Kc3 Rd1 7. Kc2 Rd4) Rc4+ 7. Qxc4=/=
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-01-06T13:42:00.807Z
Answers.LastActivityDate: 2016-01-06T13:57:50.187Z
Answers.LastEditDate: 2016-01-06T13:57:50.187Z
Answers.UserDisplayName: ferit
Answers.Body: <p>There are situations where promotion to a knight leads to draw and promotion to a queen leads to stalemate.  In these cases rook or bishop may be necessary to cash in the full point.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-01-06T13:06:30.457Z
Answers.Text: Whatever you are stating, show it on chess board.
Answers.UserDisplayName: Sufyan Naeem
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-06-02T10:53:56.960Z
Answers.Text: [FEN "2r5/kP6/8/1K6/8/8/8/8" w - - 1 0]  bxc8=Q is stalemate.  bxc8=N+ is a draw.  bxc8=B is a draw.  bcx8=R allows the black king exactly one legal move, and then wins.  Anything else loses the pawn, and the game.
Answers.UserDisplayName: Jivan Scarano
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-08T22:16:17.357Z
Answers.Text: Do you mean "cash in the full point"?
Answers.UserDisplayName: Acccumulation
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2016-01-06T12:54:59.457Z
Answers.LastActivityDate: 2019-04-19T16:19:02.040Z
Answers.LastEditDate: 2019-04-19T16:19:02.040Z
Answers.UserDisplayName: Jester
Answers.Body: <p>Sometimes a rook or bishop is preferable to a queen. I.e., when stalemate is an issue.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-13T06:27:56.303Z
Answers.Text: Anyone care to explain the downvote?
Answers.UserDisplayName: Inertial Ignorance
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-04-19T15:43:26.567Z
Answers.Text: It wasn't me, but my guess is that it was because that answer had already been given three times, and with more detail.
Answers.UserDisplayName: itub
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-04-20T05:26:37.227Z
Answers.Text: mm ok. I can see that as a reason for no upvotes but not for a downvote.
Answers.UserDisplayName: Inertial Ignorance
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-09T09:36:44.193Z
Answers.LastActivityDate: 2019-04-19T15:32:48.080Z
Answers.LastEditDate: 2019-04-19T15:32:48.080Z
Answers.UserDisplayName: Inertial Ignorance
Body: <p>Queen, in a sense, is equivalent to Bishop and Rook. What is the logic behind "putting Rook and Bishop" in the promotion move's options? Why doesn't it (Promotion move) provide the choice between Queen and Knight only? Why would one promote his Pawn to Rook or Bishop other than Queen? Promoting to Rook/Bishop instead of Queen may provide smaller advantage than promoting to Queen, and it may even provide a disadvantage to the mover. </p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-01-06T13:08:14.237Z
Comments.Text: Related to http://chess.stackexchange.com/questions/725/what-are-some-examples-of-promoting-a-pawn-to-a-rook-or-bishop?rq=1 . Sometimes choosing a queen is a mistake, and choosing a rook or bishop is correct, mostly for reasons related to stalemate.
Comments.UserDisplayName: RemcoGerlich
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-01-06T14:04:55.610Z
Comments.Text: Apart from technical reasons given below, the question is actually the reverse, why limit to Q and N only? Rules should be kept as simple as possible, unless it hurts the gameplay. Simplicity is beauty.
Comments.UserDisplayName: jf328
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-04-20T10:12:48.790Z
Comments.Text: Limiting to queen/knight would also disallow underpromotion for psychological reasons, as in: you haven't resigned that lost position a long time ago, let me torture you by mating you with knight and bishop...
Comments.UserDisplayName: user1583209
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-04-22T19:45:51.897Z
Comments.Text: Honestly, the rules of chess do not allow pawns to "promote" to pawns on the 8th rank - but there wouldn't be any obvious harm to it as far as I can see. A pawn on the 8th could not move or capture but it does take up space which could be useful in some rare cases.
Comments.UserDisplayName: Andrew Brooks
Tags: <rules><pawn-promotion>
Title: Why doesn't Promotion restrict choices to Queen and Knight only?
ThreadText: # Why doesn't Promotion restrict choices to Queen and Knight only?
  
  (Asked by: username_0 on 2016-01-06)
  
  Queen, in a sense, is equivalent to Bishop and Rook. What is the logic behind "putting Rook and Bishop" in the promotion move's options? Why doesn't it (Promotion move) provide the choice between Queen and Knight only? Why would one promote his Pawn to Rook or Bishop other than Queen? Promoting to Rook/Bishop instead of Queen may provide smaller advantage than promoting to Queen, and it may even provide a disadvantage to the mover.
  
  **Tags:** rules, pawn-promotion
  
  > **Comments:**
  > **username_1**: Related to http://chess.stackexchange.com/questions/725/what-are-some-examples-of-promoting-a-pawn-to-a-rook-or-bishop?rq=1 . Sometimes choosing a queen is a mistake, and choosing a rook or bishop is correct, mostly for reasons related to stalemate.  
  > **username_2**: Apart from technical reasons given below, the question is actually the reverse, why limit to Q and N only? Rules should be kept as simple as possible, unless it hurts the gameplay. Simplicity is beauty.  
  > **username_3**: Limiting to queen/knight would also disallow underpromotion for psychological reasons, as in: you haven't resigned that lost position a long time ago, let me torture you by mating you with knight and bishop...  
  > **username_4**: Honestly, the rules of chess do not allow pawns to "promote" to pawns on the 8th rank - but there wouldn't be any obvious harm to it as far as I can see. A pawn on the 8th could not move or capture but it does take up space which could be useful in some rare cases.  
  
  ---
  
  ## 4 answers
  
  ### Answer by username_1 on 2016-01-06. Score: 31
  
  Sometimes, choosing a bishop or a rook is the best move, because of stalemate possibilities. This happens most often with rooks, and very rarely with bishops.
  For instance, in this famous position from the Saavedra problem:
  [FEN "8/2P5/8/8/3r4/8/2K5/k7 w - - 0 1"]
  
  If white plays 1.c8Q, then black plays 1...Rc4+. White needs to take it or lose his queen but after 2.Qxc4 it is stalemate.
  If instead white plays 1.c8R, the stalemate trick doesn't work and 2.Ra8+ with checkmate next move is threatened. So black must play 2...Ra4, but white plays 3.Kb3 attacking the rook and also threatening 4.Rc1 checkmate; black can't deal with both threats.
  On Tim Krabbe's page on practical minor promotions I found this example from Kholmov-Ehlvest 1983:
  [FEN "2k5/2P5/1K2p3/7r/8/8/7p/R7 b - - 0 1"]
  [StartFlipped "0"]
  
  (black to move)
  White threatens to play Ra8+ and c8Q+. If black promotes to a queen with 1...h1Q, then that isn't enough for black to win: 2.Ra8+ Qxa8 is stalemate.
  Promoting to a rook or knight clearly doesn't help black.
  But after 1...h1B, the check doesn't work, black is simply a piece up and has a winning position.
  
  > **Comments:**
  > **username_5**: +1 because stalemate. Definitely the correct answer  
  
  ---
  
  ### Answer by username_6 on 2016-01-06. Score: 7
  
  There are 3 types of piece moves in chess:
  
  Straight
  Diagonal
  Knight-move
  
  There are positions, where promoted piece takes away the last square that enemy king can move, and stalemates. This happens because of one of these move types.
  To avoid stalemate and win eventually, you have to select a promotion which doesn't have stalemating move, which is called underpromotion.
  For example, if diagonal move stalemates, you can't select queen as it has diagonal move ability. But you can select a rook, and go for a win.
  Example from famous Saavedra position:
  [FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 1 1"]
  [Title "Saavedra"]    
  
  1. c7 Rd6+ 2. Kb5 Rd5+ 3. Kb4 Rd4+ 4. Kb3 Rd3+ 5. Kc2 Rd4 6. c8=Q ( 6. c8=R Rc4+
  
  7. Rxc4 Ka2 8. Ra4# ) (6.Kc3 Rd1 7. Kc2 Rd4) Rc4+ 7. Qxc4=/=
  
  
  ---
  
  ### Answer by username_7 on 2016-01-06. Score: 3
  
  There are situations where promotion to a knight leads to draw and promotion to a queen leads to stalemate. In these cases rook or bishop may be necessary to cash in the full point.
  
  > **Comments:**
  > **username_0**: Whatever you are stating, show it on chess board.  
  > **username_8**: [FEN "2r5/kP6/8/1K6/8/8/8/8" w - - 1 0]  bxc8=Q is stalemate.  bxc8=N+ is a draw.  bxc8=B is a draw.  bcx8=R allows the black king exactly one legal move, and then wins.  Anything else loses the pawn, and the game.  
  > **username_9**: Do you mean "cash in the full point"?  
  
  ---
  
  ### Answer by username_10 on 2019-03-09. Score: 0
  
  Sometimes a rook or bishop is preferable to a queen. I.e., when stalemate is an issue.
  
  > **Comments:**
  > **username_10**: Anyone care to explain the downvote?  
  > **username_11**: It wasn't me, but my guess is that it was because that answer had already been given three times, and with more detail.  
  > **username_10**: mm ok. I can see that as a reason for no upvotes but not for a downvote.  
  
  ---
  
  