The Hardest Mate in 1 ever.

Great tricky puzzle, but you forgot to mention it is a specifically a mate in 1. Otherwise a perfectly reasonable solution (the one I would use) would be Rfxf7 Kh8 Rxh7#

Oh right... nevermind then.

He mentioned it when he started this thread... But as some people, including me, had decided that it's impossible task... one move mate... they begun to suppose other solutions with two moves mate.

Here is a variant that works! It is standard chess + the Madrasi condition. Madrasi means that units of the same type (Q, R, B, N, P but not K) attacking each other, freeze one another. Example in the diagram: Rb8 and Rb7 are frozen. They cannot play again or give check until one of them is captured by another type piece.

White mates in 1 in the diagram - which is legal and could occur in a regular chess game played with or without the Madrasi condition.

Solution in white characters (highlight to see):

[[ 1. dxe6 e.p. #  The en passant move is legal because the white king is in check and e7-e5 is the only legal last move. The reason is that any other last move would be illegal because it violates the Madrasi freeze condition e.g. Qb6-d8+ or Re7-e8+. Note that the en passant move freezes Qd8 by Qd1. Also note that 1 ... f7-f6 is illegal because Pf7 is frozen by Pe6 and not because Rb7 checks the king - Madrasi. ]]

Did not find it. But as it happens this position is effectively impossible to reach in game, I don't feel so bad anymore.

It's standard chess but with an extra rule, Madrasi, which is explained in my previous post. After dxe6 e.p., the queen on d1 and the queen on d8 attack ech other and are therefore paralyzed (frozen). That disables the check of the black queen.

With standard chess rules, it is very difficult to prove the right to play an e.p. move but it is considerably easier with the help of the Madrasi device.

Found it! (highlight for answer)


1. c8=R ... d4
2. Nc7#

c8=Q d4 Qb7#

@Arisktotle Nice one! I'm just surprised you'd post a position involving unorthodox rules when some people here don't even comprehend the orthodox problem rules.  One question though - many of the units in your problem seem unneeded and I was wondering why you added them? 

Thx! I tried to stay as close as possible to the original post in this thread and also paid some attention to making the diagram "just legal". Not so easy to see how it could come about in a chess game played with the Madrasi condition.

It is possible to show this idea in a version without the 2 ugly white queens but the position would then look very different.

I am familiar with the combination of fairy chess with retrograde analysis and it is becoming increasingly popular amongst retro composers. I favor the viewpoint that one should assume that the proof games are played by the same rules as indicated in the problem stipulation.

it is easy pawn takes on e6

STOP REVEALING WHITE TEXT!!! NOW DELETE THAT POST!!!

Mate in 3.

I see mate in 2 with Rf7+, Kh1, Qf6#

Oopses! I edited it!

Is this mate in 1 or is it mate in 2 ? Prove your answer by analyzing the moves preceding the diagram! Standard chess rules and conventions apply as explained by Rocky64 in post #43.

Neither!

Okay, that makes sense! Yes, I agree with that idea about the legality of fairy problem positions.