user3456: I ask about the exact rules for the chess variant known as pawn wars. The starting position contains only pawns which move exactly like in chess and the first to promote wins.
[FEN "8/pppppppp/8/8/8/8/PPPPPPPP/8 w - - 0 1"]
[Title "The first to promote wins"]

But it should also be stated how to evaluate the end result when the side to move has no legal moves left. Is it lost or stalemated? I have been thinking about this game for years as a study tool for beginners but also as a philosophical research project into the game of chess for advanced players. I have found it recommended on several websites by kid educators.
I would like to write an engine to play this game but I cannot make up my mind on the best statement of the rules to maximize its practical relationship to chess. Are there any guidelines by experienced educators or existing environments to play this game? Any ideas how and why to fix the rules?

user-1: A situation like this, with Black to move, is a win for White:
[FEN "8/8/8/3pP3/3P4/8/8/8 w - - 0 1"]

Why? Well consider the case where White has been skillful enough to take all of Black's pawns and promotes easily. By definition, Black has no legal moves. From a training game we do not want to teach that losing all material leads to a forced draw. That would be a poor lesson to learn for building a knowledge of King and Pawn endings on.
A note on passing. It seems that to implement this in a program, a player with no legal moves is forced to 'pass', just in case a situation arises that allows the 'stalemated' side to have a legal move later on.

user15415: The common version of the rules for pawns-only chess (or pawn wars) states that the stalemated player loses, see https://www.chessvariants.com/diffsetup.dir/pawnsonly.html and Is the result in mini-chess known with perfect play?. In the latter thread you can also find the outcome of the game with perfect play in case you are interested.

3456: <p>I ask about the exact rules for the chess variant known as pawn wars. The starting position contains only pawns which move exactly like in chess and the first to promote wins.</p>

<pre><code>[FEN "8/pppppppp/8/8/8/8/PPPPPPPP/8 w - - 0 1"]
[Title "The first to promote wins"]
</code></pre>

<p>But it should also be stated how to evaluate the end result when the side to move has no legal moves left. Is it lost or stalemated? I have been thinking about this game for years as a study tool for beginners but also as a philosophical research project into the game of chess for advanced players. I have found it recommended on several websites by kid educators.</p>

<p>I would like to write an engine to play this game but I cannot make up my mind on the best statement of the rules to maximize its practical relationship to chess. Are there any guidelines by experienced educators or existing environments to play this game? Any ideas how and why to fix the rules?</p>
 -1: <p>A situation like this, with Black to move, is a <strong>win</strong> for White:</p>

<pre><code>[FEN "8/8/8/3pP3/3P4/8/8/8 w - - 0 1"]
</code></pre>

<p>Why? Well consider the case where White has been skillful enough to take all of Black's pawns and promotes easily. By definition, Black has no legal moves. From a training game we do not want to teach that losing all material leads to a forced draw. That would be a poor lesson to learn for building a knowledge of King and Pawn endings on.</p>

<p>A note on <strong>passing</strong>. It seems that to implement this in a program, a player with no legal moves is forced to 'pass', just in case a situation arises that allows the 'stalemated' side to have a legal move later on.</p>
 15415: <p>The common version of the rules for pawns-only chess (or pawn wars) states that the stalemated player loses, see <a href="https://www.chessvariants.com/diffsetup.dir/pawnsonly.html" rel="nofollow noreferrer">https://www.chessvariants.com/diffsetup.dir/pawnsonly.html</a> and <a href="https://chess.stackexchange.com/questions/8755/is-the-result-in-mini-chess-known-with-perfect-play/23275">Is the result in mini-chess known with perfect play?</a>. In the latter thread you can also find the outcome of the game with perfect play in case you are interested.</p>
