As stated in the title, white must mate black in 1 move. But first you must solve the mystery behind this puzzle.
This puzzle was created by Hieronymus Fischer (1843-1927).
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Sign up to join this communityThe mystery
There are 9 pawns on the board (black supremacy propaganda?). If we remove any of them to make it legal, we can mate in 1.
The mate
Remove a7, 1. Qb6#
Remove b7, 1. Nc6#
Remove c4, 1. Qb4#
Remove d3, 1. Qe4#
Remove e3, 1. Bxf2#
Remove f7, 1. Ne6#
Remove f2, 1. Bxe3#
Remove g6, 1. Rg4#
Remove h3, 1. Rh4#
Additional note
We note the double pawns occur on the f file. A potential question could be whether we could remove any of the pawns and still have the board position reachable legally. The answer is that no pawn removal matters. For example, if we removed the a7 pawn, the pawn that is currently at f2 originally started at a7 and with sequential captures traversed a7, b6, c5, etc to reach f2. We can similarly show that for any other pawn from any file, the pawn at f2 could have started from that file and reached f2 legally.
A possible explanation to the mystery:
This is tandem chess.
In which case:
You might have a queen or a rook in your deck. Drop it on d5... quickly!
Alternate solution that does not notice or take care of the excess of black pawns
The mystery:
The board is oriented opposite the usual direction: white started at the top and white pawns advance toward the bottom of the board.
The mate:
Queen to a1 or b2. Black can't interpose the pawn because his pawns advance up the board.
Note:
We have to assume that the black pawn at d3 got there by capturing something after the white pawn at d2 obtained that position. No explanation for the pure number of pawns that have not already queened.
Another alternate solution: The pawns are Berolina pawns (which move diagonally and capture straight ahead; thus, the pawns on d2 and d3 are threatening each other); and Black gave odds by replacing his queen with another pawn on d8.
This allows Qb2 (or Qa1) mate.
1. Qb2 c3
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