Unusual LOA endgames


Simultaneous Connection

The canonical "unusual endgame" is this, where both players achieve a winning position simultaneously. In this case, according to the rules, the player moving wins. 

In this situation, white wins by capturing the black stone in the center. After the capture, both players have only one group. 

Zugzwang ! (compulsion to move)

This position, discovered by Roel van der Goot , shows a situation where both players would clearly prefer not to move.  Of course, the rules don't provide that choice, so the next player must move, and lose.

An interesting Historical note

I should start the discussion of unusual endgames by noting that in the original 1969 edition of A gamut of Games, sumultaneous connection was described as a draw! In the second edition, the rules were changed to declare this a win for the player moving. The apparent intent is to eliminate all possible draws from the game, and in that spirit any other abnormal situations that may arise should also not result in draws. Here is Sid Sackson's note in the preface to the second edition:
Claude Soucie and I are all that remains of N.Y.G.A. At his request, I have corrected an error in the rules for LINES OF ACTION, eliminating possible draws.
What other situations are there? For one, there is the definite possibility of endlessly repeating sequences, which neither player is willing to change. When I first posed this question to NOST members, it was mostly dismissed as unlikely to happen, and therefore unimportant. But since then, a possible endless repetition has come up in a real game.

What other other potential draw situations are there? I can't think of any that can occur the standard game, but maybe you can? I don't think it is possible to construct a position where neither player can move, but it clearly is possible to create positions where one player or ther other has no moves.

comments/suggestions to: ddyer@real-me.net

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