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The [[Draw|draw]] motive is a [[stalemate|stalemate]] threat, after the defending king blocks its own pawn after a queen check on the neighbouring knight file, so that the attacking king can't come closer.
A [[Distance|Chebyshev Distance]] of at least four to the [[Promotion Square|promotion square]] with a [[Manhattan-Distance|Manhattan distance]] less than eight for the attacking king is necessary to win that game (<span style="background-color: #c0ffc0;">green area below</span>).
However, the attacking king may reduce the distance by [[Discovered Check|discovered check]]
While implementing this pattern inside a [[Interior Node Recognizer|interior node recognizer]], one has to take care that with the king in the corner (i.e. black king on a1), the queen has no mate in one (i.e. on c1).
{|| <fentt border="double" style="font-size:24pt">...Q..../......../......../(....)K.../(.....).../(.....).../(pk...).../(.k...)...</fentt>| <fentt border="double" style="font-size:24pt">.......Q/......../......../(....)K.../(.....).../(.....).../(pk...).../(kk.....)...</fentt>|-| Draw| Win due to [[Discovered Check|discovered check]]|}
<span id="BishopPawn7"></span>
=Bishop Pawn on 7th=
and the diagonal neighbouring square on the lee-side one rank back (i.e. for black pawn on c2, [[Distance|ϑ(♔,b3)]]).
<ref>[[Interior Node Recognizer]] implemented in [[IsiChess]]</ref>
* Attacking king may reduce distance by [[Discovered Check|discovered check]]
* With a <span style="background-color: #c0ffc0;">distance below two</span> to any of these critical squares, the game is won.
* A <span style="background-color: #cc80cc;">distance of two</span> to any of these critical squares is not sufficient, if the defending king occupies the corner square (i.e. a1), or the 7th/8th (1st/2nd) rank on the neighbouring knight file (i.e. b1, b2).
* Exception: attacking king can immediately capture pawn
* A distance of two is required to win the game otherwise
{|| <fentt border="double" style="font-size:24pt">...Q..../......../......../{....}..../(...){K...}./(.+....){.}./(.kp.+.){.}./{kk.}(...){.}.</fentt>| <fentt border="double" style="font-size:24pt">.......Q/......../......../{....}..../(...){.K...}./(.+....){.}./(.kp.+.){.}./{kkk..}(...){.}.</fentt>|-| Draw| Win due to [[Discovered Check|discovered check]]|}
=See also=
* [[Draw Evaluation]]
