Answers.Body: <p>No. Think of a position like White king on f2 versus Black pawn on h2 and Black king on h1. Black is stalemated, but adding the extra outer squares would not turn this into a win for White, but rather into a draw by repetition (...Ki2 Kg3! and now Kh1 is the only legal move</p>
  
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Answers.Text: ah right! I forgot about the case where the stronger side is stalemated. Using retrograde analysis, however, we can see that White cannot force Black to step on h1 **and** lock himself in by advancing his pawn, therefore, this position would not be reached by *perfect play*. Nevertheless, +1 for this idea, Kg3!! is genius, I love it :) :)!
Answers.UserDisplayName: Hauptideal
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Answers.Text: @Hauptideal wouldn't it be possible if the king reaches h1 at some point and then the pawn gets pushed forward?
Answers.UserDisplayName: David
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Answers.Text: Last moves before that position: wRxbQh1, bKxRh1, wKf2. Looks legit to me.
Answers.UserDisplayName: Hauke Reddmann
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Answers.Text: @HaukeReddmann but Kxh1 is not forced (Black is not losing if he does not take the rook). Its a draw in regular chess, stalemate-wins-chess and this new variant. If you make the wR a wQ to force him to take, then White would win, no matter whether the constellation is bKh2, bph3 or bKg2, bph2. (And it might be that even that starting position cannot be forced).
Answers.UserDisplayName: Hauptideal
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Answers.Text: @Hauptideal I assumed we meant "optimal play from any given position". Otherwise all variants of chess where the theoretically expected result is a draw would be equivalent to each other.
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Answers.Text: @David I get the argument that we might start from any given position, including a "stalemated" black king. However I found another issue with the answer: **Black wouldn't go Ki2, but Kh0!** White cannot prevent promotion, as he can not make contact with the pawn without keeping the Black king out of the regular board, allowing a promotion. If White moves Kg3 however, Black can get to g1 and promote the pawn!
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Answers.Text: @Hauptideal 1...Kh0 Kf1 and now Black is forced to go back to the board with his king (Kh1 being the only legal move that allows that)
Answers.UserDisplayName: David
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Answers.Text: @David thanks, completely overlooked this
Answers.UserDisplayName: Hauptideal
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Body: <p>Most drawn endgames where one side is stronger than the other (e.g. has an extra pawn) are drawn because the weaker king can force being stalemated on the rim if the stronger side avoids a repetition.
  Let's assume we add an additional rank/file at each side of the board so that the board would have a size of 10x10.
  The chess game would be played on the inner 8x8 board just like regular chess. The only exception is, that</p>
  <ol>
  <li>a king that is not in check can and must step on the outer area if and only if there are no other legal moves and</li>
  <li>must move back into the regular board as soon as it becomes legal.</li>
  </ol>
  <p>Would this in effect be equivalent to declaring a stalemate on the board edge a win for the stronger side with perfect play?</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-11-21T12:51:18.010Z
Comments.Text: Offhand I can't see how 2N shall force mate with this mechanism in effect. Forcing stalemate is easy in contrast.
Comments.UserDisplayName: Hauke Reddmann
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Comments.CreationDate: 2022-11-22T01:14:05.280Z
Comments.Text: Oh right, I should add the rule, that the king can only leave the board if it is not in check.. Thanks
Comments.UserDisplayName: Hauptideal
Tags: <chess-variants><stalemate>
Title: Would a stalemate declared a win be theoretically equivalent to this larger board chess variant?
ThreadText: # Would a stalemate declared a win be theoretically equivalent to this larger board chess variant?
  
  (Asked by: username_0 on 2022-11-21)
  
  Most drawn endgames where one side is stronger than the other (e.g. has an extra pawn) are drawn because the weaker king can force being stalemated on the rim if the stronger side avoids a repetition.
  Let's assume we add an additional rank/file at each side of the board so that the board would have a size of 10x10.
  The chess game would be played on the inner 8x8 board just like regular chess. The only exception is, that
  
  1. a king that is not in check can and must step on the outer area if and only if there are no other legal moves and
  2. must move back into the regular board as soon as it becomes legal.
  
  Would this in effect be equivalent to declaring a stalemate on the board edge a win for the stronger side with perfect play?
  
  **Tags:** chess-variants, stalemate
  
  > **Comments:**
  > **username_1**: Offhand I can't see how 2N shall force mate with this mechanism in effect. Forcing stalemate is easy in contrast.  
  > **username_0**: Oh right, I should add the rule, that the king can only leave the board if it is not in check.. Thanks  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2022-11-21. Score: 6 | Accepted answer
  
  No. Think of a position like White king on f2 versus Black pawn on h2 and Black king on h1. Black is stalemated, but adding the extra outer squares would not turn this into a win for White, but rather into a draw by repetition (...Ki2 Kg3! and now Kh1 is the only legal move
  
  > **Comments:**
  > **username_0**: ah right! I forgot about the case where the stronger side is stalemated. Using retrograde analysis, however, we can see that White cannot force Black to step on h1 **and** lock himself in by advancing his pawn, therefore, this position would not be reached by *perfect play*. Nevertheless, +1 for this idea, Kg3!! is genius, I love it :) :)!  
  > **username_2**: @username_0 wouldn't it be possible if the king reaches h1 at some point and then the pawn gets pushed forward?  
  > **username_1**: Last moves before that position: wRxbQh1, bKxRh1, wKf2. Looks legit to me.  
  > **username_0**: @username_1 but Kxh1 is not forced (Black is not losing if he does not take the rook). Its a draw in regular chess, stalemate-wins-chess and this new variant. If you make the wR a wQ to force him to take, then White would win, no matter whether the constellation is bKh2, bph3 or bKg2, bph2. (And it might be that even that starting position cannot be forced).  
  > **username_2**: @username_0 I assumed we meant "optimal play from any given position". Otherwise all variants of chess where the theoretically expected result is a draw would be equivalent to each other.  
  > **username_0**: @username_2 I get the argument that we might start from any given position, including a "stalemated" black king. However I found another issue with the answer: **Black wouldn't go Ki2, but Kh0!** White cannot prevent promotion, as he can not make contact with the pawn without keeping the Black king out of the regular board, allowing a promotion. If White moves Kg3 however, Black can get to g1 and promote the pawn!  
  > **username_2**: @username_0 1...Kh0 Kf1 and now Black is forced to go back to the board with his king (Kh1 being the only legal move that allows that)  
  > **username_0**: @username_2 thanks, completely overlooked this  
  
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