I played this game Game 3183355 recently and it was an interesting one so I ran it through shredder to take another look at it. It turns out that I missed a forced checkmate on move 25!

I was wondering if anyone knew of any software that would let me look through previous games to search for other missed mates or big missed chances using open source engines. Ideally, the program would run all night and spit out any games where a missed mate was detected for either player...

Originally posted by reyotch
I played this game Game 3183355 recently and it was an interesting one so I ran it through shredder to take another look at it. It turns out that I missed a forced checkmate on move 25!

I was wondering if anyone knew of any software that would let me look through previous games to search for other missed mates or big missed chances using open sourc ...[text shortened]... would run all night and spit out any games where a missed mate was detected for either player...

I don't know... but I'm interested in seeing the forced mate on move 25!

Originally posted by ChessJester
I don't know... but I'm interested in seeing the forced mate on move 25!

Originally posted by adam warlock
At first I thought on 25. Rg4 but i think 25.qd8 stops it...

Originally posted by Kepler
Rh4 I think.

Originally posted by Kepler
Rh4 I think.

26. Rh4 gxh4 27. Rxg6 fxg6 28. Qg7# is what I saw. I didn't check for any reasonable defenses. 26. Rh4 popped out at me pretty quickly.

25 Rh4 g5xRh4
26 Rg1 rg8xRg1+
27 Kxg1 other than kf3+
28 Qg7#

If 27kxg1 kf3+
28 Kxf3 anymove
29 Qg7#

this are the lines aren't they?

25. Rh4! leads to mate in six according to Fritz 10.

25... gxR 26. Rg1 and the mate follows soon after.

Whoops, too late

25.Rh4 threatens mate on h7 if someone was wondering why it works... black can't defend h7 because if he does with Rg7 then Qxg7# so 25...gxh4 is the only move. What you also have to see is that it will take black 2 moves to defend g7 if the g8 rook is drawn away from it, so when black plays 26...Rxg1+ (after 26.Rg1) white has time to take back with the king. If black doesn't play Rxg1+ then black has to defend g8 because white threatens to play Rxg8+ followed by Qg7# but if black does that by moving his bishop or bringing the queen onto the back rank white makes another mating threat on h7 with Rg7, this is why black has to play Rxg1.

This is all made possible by the pawn at f6!

Yeah, I thought forever during the last 10 moves of this game... I went back and forth between thinking that my attack was doomed and my opponent was crushed. Finally I found a winning combination, but it was touch and go there for a while.

In fact, I almost convinced myself that after 26. Qf8+ that I should offer a draw since I couldn't see how to proceed - glad I didn't!