CHECK THIS MATE IN TWO

White mate in two           by J.Fulpius

This problem violates the standard problems conventions since there are two open black checks (checks that white can't answer with mate) on c2 and d3 in the diagram. However, this clearly is a special task constructed to show the maximum amount of black checking defenses possible and it is only natural that such a composition would contain a few open checks. Ideas are more important than rules, so this is a wonderful problem!

@ Arisktotle I missed  some answers in the solution sorry  1...Qc2 2.Rxc2#  1...Qd3 2.Nxd3#  I am double checking, if there were any mistakes it is not the puzzle but my diagram of it.I also thought this puzzle fantastic wanted to share it.

These mates are completely correct. My comment does not concern the correctness but the appreciation of this problem and similar problems in general.

If white "passes" (this is called "set play") in the diagram then black could check with his queen on d3 or c2 and white could not mate in one move - a so called "open check". This is considered a weakness in a problem composition as it means that white must take precautions against these 2 checks.

Example: I do not need to consider a key move like 1.f8N since it does not defend against the open checks on d3 or c2. Very few moves do and therefore very few key move candidates remain!

When you examine many composed problems you will see there are few if any with open check threats by black. All composers know you shouldn't leave any open checks in a diagram and therefore avoid them. In this particular problem they are not a big issue considering the task the composer took upon himself!

@Arisktotle I must admit you lost me. Are you saying that the positions make the key move too obvious? I found this puzzle extremely difficult because of the moves you bring up.I seen this puzzle in a book preview that describes it as a record 13 open checks possible by black in a strategic two mover.All of the text was not there it was just a preview but it was about record setting puzzles.

Just read exactly what I wrote. I am talking about open black checking threats in the diagram not after the key move. If white plays an arbitrary key move (think: passes) , then black replies with Qc2+/Qd3+ and you cannot checkmate him. Therefore white can pick here from just 3 key moves which disarm these checking threats and that makes the solution easy to find.

It is important to understand this idea and compare it with the other check type. In many problems black can give check in the diagram (if white passes) but white replies with checkmate. Then the check does not restrict the white key move options and is no composition flaw!

Note: in a threemover, an open black check in the diagram is only permitted if white could then forcibly mate him in 2 moves. If you think about it, you will see the logic.

By the way, "record setting puzzles" are often referred to as "tasks". When you meet such a description you know you are dealing with some sort of record (attempt). Tasks sometimes break composition conventions but the composers are mostly forgiven!

This reminds me of Nabokov's puzzles

      @ Arisktotle I think I see what you mean,when I was solving the puzzle those very moves are what made me move the king,when I finally seen I could then answer the checks with mate.I did not see the text about being a record black checking white till after I solved.LOL I thought wow I solved a record puzzle.Hey I am learning and your input is a great help.

@sameez1: You're welcome and well done for solving this one!