Thanks <Phony Benoni> Thats how it looked to me.

The position occurred in a puzzle. Not only was the e.p. capture the only legal move it was the last as well. The capture resulted in self-mate.

I checked Ne5, Ng5 and Nd4, all playable, all with advantage wihte, but none of the moves as good as Ng1!

There's a nice finish to the text position if black decides to play on with 12...Be4. White follows with 13 Qa4+!.

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Note that if black tries to interpose a piece on c6 beside the bishop white wins a piece with Nxe4 and still has the queen trapped.

And If black plays 13...Bc6, white simply plays 14 Qxh4.

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J Blake vs G A Hooke, 1891

Dzindzichashvili vs Zacharov, 1957

In both cases Qxg2 is the best move. On other moves the best replies have not been talked about for White.

For instance, with Ng5 Qh4 marginally best is Ndf3 instead of g3. Not that g3 doesn't work, but Nf3 turns out considerably better as you play through variations.

So I would say both Ng5 and Ng1 were solutions with Nd4 enough inferior to disqualify it.

With just one exception, I think. If an en passant capture is the only legal move <and> it leads to an inevitable draw then I think it cannot be played. The laws state that a game is drawn immediately if a position arises that cannot be won by either side by any combination of moves.

I guess that prettiness is in the eye of the beholder...

Black has been playing with fire and now gets his fingers burnt: 11 Ng5 and now (A) 11...Qxg2 12 Bf3 Qxh1+ 13 Bxh1 and if 13...fxg5 14 Bxb7; (B) 11...Qh4 12 g3 Qxg5 13 Bxg5 fxg5 14 Bf3 should win on material. If 12...Qh6 13 Nf7 Qh3 and White can choose between 14 Nxh8 and 14 Bf1 harassing the Q further but there's no need to decide this when playing 11 Ng5. Time to check:
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Puzzle position

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White plays 11 Ng1! even better. Have I messed up? Crafty End Game Trainer link: http://www.chessvideos.tv/endgame-t... 11 Ng5 wins but I had missed Black's best defence 11...Qxg2 12 Bf3 Bg4! as pointed out by other kibitzers and which limits Black's losses to a piece for a Pawn. The EGT defends the resulting lost position tenaciously and I won third time round (blundering badly the first two times).

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White plays <1.g4+>. Black's only legal move is <1...fxg3>, but that produces "an inevitable draw" by stalemate. Are you saying the move cannot be played, and therefore White wins by checkmate? (And before someone asks, the position is legal.)

However, I'm sure you're actually talking about a draw by lack of mating material. In that case, I don't think there is such a position. After an <en passant> capture at least one pawn remains on the board, and that's always mating material.

But perhaps this is the time to recount The Great <En Passant> Swindle.

Our position is from a game at the 1977 US Open between the charitably named NN (White, rated 1011) and Sneaky Pete (Black, rated 1209). No, not the chessgames.com kibitzer, but a computer--and remember, this is a 1977 model computer. In true puzzle fashion, it's <61...?>

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Black is lost. As much as he would love to play 61...b5#, White has this forced <en passant> capture in reply, when his king will easily escape and Black's bishop will soon go lost. But Sneaky Pete came up with the brilliant <61...b6!!>.

Of course, White could just enter the winning line with 62.cxb6, but it isn't forced and he has a chance to blunder. And sure enough, White cooperated: <62.Nxc6?? b5+ 63.Ka5 Ra3#!>

8.c3.. not in first five. -5.

8...Bd6.not in first five. -5.

9.Be3. 4th best. -3.

10...Qg4.5th best. -4.

11...Qh4.5th best. -4.

No. 1 candidate move = 0.
Deviations from that = 1 penalty point per rated level. maximum 5.
Black 18, White 8, and a win for white, Black resigning after 12.g3, +7.09.

<9.6 The game is drawn when a position is reached from which a checkmate cannot occur by any possible series of legal moves. This immediately ends the game, provided that the move producing this position was legal.>

This is the law which produces the draw by insufficient material. But we had a discussion a few months ago about other situations when this law kicks in. Take this silly position:

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In a desperate time scramble White has just played Qf7+. Black's flag falls before he can play Kxf7 to get a draw by insufficient material. Does black lose on time? When we talked about this before we didn't think so. Rule 9.6 says that the game is drawn immediately that a position is reached where checkmate cannot happen by any legal series of moves. In this position, black has to play Kxf7 leading to an inevitable draw. This means that he cannot play Kxf7 because the game is already drawn. The proper sequence of events would be 1. Qf7+ draw.

Note that this law is not triggered by either playing claiming the draw. It is absolute. It also has to be any possible series of legal moves, not best play.

The law also kicks in in stalemate positions or positions where neither side can make progress, like this one:

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This position is a draw the instant that the pawns are locked because there is no way for either king to get across the board.

So the situation we wanted was one where one player has to play an en passant capture and his opponent is not allowed to recapture because rule 9.6 has kicked in.

And your diagram does this perfectly. White plays 1. g4+ and the game is immediately drawn. We have produced a position which cannot be won by an series of legal moves. Black does not have to play fxg (ep) draw. And a strict interpretation of 9.6 is that he cannot play this. The game was drawn as soon as white played g4+.