Unusual mate in two (56)

White mates in two by Schiffman,A.C.White,W.Kramer

Took me 5 hours to solve this. Tricky. Nice puzzle m8.

Indeed, unusual but intriguing! Fortunately black threatens .. Nc6+ which helped me to find the key! Btw, the 4 light escape squares for the bK are called a "starflight".

@ Arisktotle 7 square flight with seperate mates, this is the record for black king,and it has the 8th Rxd5.The defect in the key has to be excused(authors words)I personally don't see a defect if it is accurate. It broke a 40 year record for 6,which I will post later.                                                Btw, the 4 light escape squares for the bK are called a "starflight".                       Yes now that you say it I can see that thanks.

What is the mate after Rxd5? The analysis board says Nd4, but that isn't mate because of Ke5.(Edit) Nevermind I found it f8=N#

I am going to try to edit that,sorry for the mistake.

The 4 dark square escapes are named a "cross flight" in dutch but I'm not sure it is the english name as well. One of those is missing and ..Rxd5 doesn't make up for that. Nevertheless it is a great record of course!

There are two "defects" we discussed before and they are related. The open check threat on c6 is a defect and white's key move check is as well; it is only justifiable by the black threat. Nevertheless, the record breaking content outranks the defects on this occasion. Record breakers are like top-athletes; they may overstep some lines that ordinary people may not.

@ Arisktotle the theoretical 8 square flight of the king with  mate is a record yet to be achieved.(You could name that puzzle the starcross flight) The extra Rxd5 mate was a nice addition to the 7 square flight I thought              The previous record of 6 had an extra mate in it too.I want to post it but i am kind of on the run right now.

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I bet that one had a checking key move as well! It is much easier to control the kings flights when its starting square is covered!

Turn off your smartphone, turn off your smart-TV. Run, Forest, run!

@ Arisktotle I posted it no checking move, a rough key  Check it out probably should  have put it on this thread.The puzzles with defects in the book are IDed thats the ones I go to first.I have the one that has two knights that mate in all 8 of the wheel, it has a capturing key and it is kind of obvious but wow.  I will post that one too. .LOL my run is wife chasing,I am TVed out,if I had smart phone would be on chess.com.

Can't find it. Where did you post it?

I posted it under more puzzles.(mate in two (57) How does that happen I remember not finding that puzzle you posted for me for more than a week...As a composer do any of these unobtained records tempt you? 

Strange I missed it. Possibly because of the similar title.

I will only go for a record when I accidently come close to one. By the way, where do I find these unobtained records? Are they on the net?

Some of the records are theoretical maximums i.e the black king only has 8 squares to run to can't be any higher than that.The same theory is applied to each piece for a theoretical maximum of that piece to run or to check like the knight wheel.Weather the record has or hasn't been obtained looks like the author of this book is the one that has compiled this information over his lifetime...I am going to post that 2 knights both using all 8 in their wheel to block or capture to mate. The more I look at it to post without making a mistake, the less I think I like it. It has a bad key.