No.766, 767 |
Original Problems, Julia’s Fairies – 2015 (I): January – June →Previous ; →Next ; →List 2015(I) Please send your original fairy problems to: julia@juliasfairies.com |
No.766, 767 by Geoff Foster – Very strange and interesting combination of fairy elements! (JV)
Definitions:
Back-To-Back: When pieces of opposite colors stand back-to-back with each other on the same file (white piece is on the top of black!), they exchange their roles. A pawn on the first rank cannot move. Any piece can make an en passant capture when it has got a role of Pawn by Back-To-Back.
Anti-Kings: A king is in check if he is not attacked. Mate occurs when a king is not attacked and his side has no move which exposes him to attack. (Of course kings may not be captured.)
No.766 Geoff Foster |
Solutions: (click to show/hide) |
White Kd7
Black Kd8
Neutral Pe6
h#2,5 2 solutions (1+1+1) |
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No.767 Geoff Foster |
Solutions: (click to show/hide) |
White Kf3
Black Kf2
Neutral Pg3 Pg2
h#2* 3 solutions (1+1+2) |
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Interesting strategy. The kings are bound by attacking/observing each other, so how can White mate? It seems when the wK gives up his attack on the bK, the bK can always walk into attack again by following the wK …
the solution in almost all lines is to have the wK walk into a BTB situation, so if the bK follows him, he is still not under attack because the wK doesn’t move like a K anymore.
The last solution of 767 is surprisingly different: the wK can give up his attack on the bK earlier, because the bK can walk into an attack from the third man (a nR) instead – and this attack can be cancelled by a white non-reversible move into a BTB situation. Whether this anti-identical solution is a valuable addition or an annoying one is debatable, I tend to like it.
My first experience with Anti-Kings. In the wake of recent discussions on short proof games, has anyone else concluded that all Anti-Kings positions (no fairy pieces) are “illegal” by default? The starting position of a game of chess under this condition is double checkmate! Game over! Actually, the condition is intriguing, flip-flopping the concept of checkmate. I suppose retro afficianados could make a proof game from the starting position, but with kings swapping squares first. Queens swapping start squares is a too easy win for white.